literature review introduction body conclusion

Purdue Online Writing Lab Purdue OWL® College of Liberal Arts

Writing a Literature Review

Welcome to the Purdue OWL

This page is brought to you by the OWL at Purdue University. When printing this page, you must include the entire legal notice.

Copyright ©1995-2018 by The Writing Lab & The OWL at Purdue and Purdue University. All rights reserved. This material may not be published, reproduced, broadcast, rewritten, or redistributed without permission. Use of this site constitutes acceptance of our terms and conditions of fair use.

A literature review is a document or section of a document that collects key sources on a topic and discusses those sources in conversation with each other (also called synthesis ). The lit review is an important genre in many disciplines, not just literature (i.e., the study of works of literature such as novels and plays). When we say “literature review” or refer to “the literature,” we are talking about the research ( scholarship ) in a given field. You will often see the terms “the research,” “the scholarship,” and “the literature” used mostly interchangeably.

Where, when, and why would I write a lit review?

There are a number of different situations where you might write a literature review, each with slightly different expectations; different disciplines, too, have field-specific expectations for what a literature review is and does. For instance, in the humanities, authors might include more overt argumentation and interpretation of source material in their literature reviews, whereas in the sciences, authors are more likely to report study designs and results in their literature reviews; these differences reflect these disciplines’ purposes and conventions in scholarship. You should always look at examples from your own discipline and talk to professors or mentors in your field to be sure you understand your discipline’s conventions, for literature reviews as well as for any other genre.

A literature review can be a part of a research paper or scholarly article, usually falling after the introduction and before the research methods sections. In these cases, the lit review just needs to cover scholarship that is important to the issue you are writing about; sometimes it will also cover key sources that informed your research methodology.

Lit reviews can also be standalone pieces, either as assignments in a class or as publications. In a class, a lit review may be assigned to help students familiarize themselves with a topic and with scholarship in their field, get an idea of the other researchers working on the topic they’re interested in, find gaps in existing research in order to propose new projects, and/or develop a theoretical framework and methodology for later research. As a publication, a lit review usually is meant to help make other scholars’ lives easier by collecting and summarizing, synthesizing, and analyzing existing research on a topic. This can be especially helpful for students or scholars getting into a new research area, or for directing an entire community of scholars toward questions that have not yet been answered.

What are the parts of a lit review?

Most lit reviews use a basic introduction-body-conclusion structure; if your lit review is part of a larger paper, the introduction and conclusion pieces may be just a few sentences while you focus most of your attention on the body. If your lit review is a standalone piece, the introduction and conclusion take up more space and give you a place to discuss your goals, research methods, and conclusions separately from where you discuss the literature itself.

Introduction:

• An introductory paragraph that explains what your working topic and thesis is
• A forecast of key topics or texts that will appear in the review
• Potentially, a description of how you found sources and how you analyzed them for inclusion and discussion in the review (more often found in published, standalone literature reviews than in lit review sections in an article or research paper)
• Summarize and synthesize: Give an overview of the main points of each source and combine them into a coherent whole
• Analyze and interpret: Don’t just paraphrase other researchers – add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole
• Critically Evaluate: Mention the strengths and weaknesses of your sources
• Write in well-structured paragraphs: Use transition words and topic sentence to draw connections, comparisons, and contrasts.

Conclusion:

• Summarize the key findings you have taken from the literature and emphasize their significance
• Connect it back to your primary research question

How should I organize my lit review?

Lit reviews can take many different organizational patterns depending on what you are trying to accomplish with the review. Here are some examples:

• Chronological : The simplest approach is to trace the development of the topic over time, which helps familiarize the audience with the topic (for instance if you are introducing something that is not commonly known in your field). If you choose this strategy, be careful to avoid simply listing and summarizing sources in order. Try to analyze the patterns, turning points, and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred (as mentioned previously, this may not be appropriate in your discipline — check with a teacher or mentor if you’re unsure).
• Thematic : If you have found some recurring central themes that you will continue working with throughout your piece, you can organize your literature review into subsections that address different aspects of the topic. For example, if you are reviewing literature about women and religion, key themes can include the role of women in churches and the religious attitude towards women.
• Qualitative versus quantitative research
• Empirical versus theoretical scholarship
• Divide the research by sociological, historical, or cultural sources
• Theoretical : In many humanities articles, the literature review is the foundation for the theoretical framework. You can use it to discuss various theories, models, and definitions of key concepts. You can argue for the relevance of a specific theoretical approach or combine various theorical concepts to create a framework for your research.

What are some strategies or tips I can use while writing my lit review?

Any lit review is only as good as the research it discusses; make sure your sources are well-chosen and your research is thorough. Don’t be afraid to do more research if you discover a new thread as you’re writing. More info on the research process is available in our "Conducting Research" resources .

As you’re doing your research, create an annotated bibliography ( see our page on the this type of document ). Much of the information used in an annotated bibliography can be used also in a literature review, so you’ll be not only partially drafting your lit review as you research, but also developing your sense of the larger conversation going on among scholars, professionals, and any other stakeholders in your topic.

Usually you will need to synthesize research rather than just summarizing it. This means drawing connections between sources to create a picture of the scholarly conversation on a topic over time. Many student writers struggle to synthesize because they feel they don’t have anything to add to the scholars they are citing; here are some strategies to help you:

• It often helps to remember that the point of these kinds of syntheses is to show your readers how you understand your research, to help them read the rest of your paper.
• Writing teachers often say synthesis is like hosting a dinner party: imagine all your sources are together in a room, discussing your topic. What are they saying to each other?
• Look at the in-text citations in each paragraph. Are you citing just one source for each paragraph? This usually indicates summary only. When you have multiple sources cited in a paragraph, you are more likely to be synthesizing them (not always, but often
• Read more about synthesis here.

The most interesting literature reviews are often written as arguments (again, as mentioned at the beginning of the page, this is discipline-specific and doesn’t work for all situations). Often, the literature review is where you can establish your research as filling a particular gap or as relevant in a particular way. You have some chance to do this in your introduction in an article, but the literature review section gives a more extended opportunity to establish the conversation in the way you would like your readers to see it. You can choose the intellectual lineage you would like to be part of and whose definitions matter most to your thinking (mostly humanities-specific, but this goes for sciences as well). In addressing these points, you argue for your place in the conversation, which tends to make the lit review more compelling than a simple reporting of other sources.

Have a language expert improve your writing

Run a free plagiarism check in 10 minutes, generate accurate citations for free.

• Knowledge Base

Methodology

• How to Write a Literature Review | Guide, Examples, & Templates

How to Write a Literature Review | Guide, Examples, & Templates

Published on January 2, 2023 by Shona McCombes . Revised on September 11, 2023.

What is a literature review? A literature review is a survey of scholarly sources on a specific topic. It provides an overview of current knowledge, allowing you to identify relevant theories, methods, and gaps in the existing research that you can later apply to your paper, thesis, or dissertation topic .

There are five key steps to writing a literature review:

• Search for relevant literature
• Evaluate sources
• Identify themes, debates, and gaps
• Outline the structure
• Write your literature review

A good literature review doesn’t just summarize sources—it analyzes, synthesizes , and critically evaluates to give a clear picture of the state of knowledge on the subject.

Instantly correct all language mistakes in your text

Upload your document to correct all your mistakes in minutes

Table of contents

What is the purpose of a literature review, examples of literature reviews, step 1 – search for relevant literature, step 2 – evaluate and select sources, step 3 – identify themes, debates, and gaps, step 4 – outline your literature review’s structure, step 5 – write your literature review, free lecture slides, other interesting articles, frequently asked questions, introduction.

• Quick Run-through
• Step 1 & 2

When you write a thesis , dissertation , or research paper , you will likely have to conduct a literature review to situate your research within existing knowledge. The literature review gives you a chance to:

• Demonstrate your familiarity with the topic and its scholarly context
• Develop a theoretical framework and methodology for your research
• Position your work in relation to other researchers and theorists
• Show how your research addresses a gap or contributes to a debate
• Evaluate the current state of research and demonstrate your knowledge of the scholarly debates around your topic.

Writing literature reviews is a particularly important skill if you want to apply for graduate school or pursue a career in research. We’ve written a step-by-step guide that you can follow below.

Receive feedback on language, structure, and formatting

Professional editors proofread and edit your paper by focusing on:

• Academic style
• Vague sentences
• Style consistency

See an example

Writing literature reviews can be quite challenging! A good starting point could be to look at some examples, depending on what kind of literature review you’d like to write.

• Example literature review #1: “Why Do People Migrate? A Review of the Theoretical Literature” ( Theoretical literature review about the development of economic migration theory from the 1950s to today.)
• Example literature review #2: “Literature review as a research methodology: An overview and guidelines” ( Methodological literature review about interdisciplinary knowledge acquisition and production.)
• Example literature review #3: “The Use of Technology in English Language Learning: A Literature Review” ( Thematic literature review about the effects of technology on language acquisition.)
• Example literature review #4: “Learners’ Listening Comprehension Difficulties in English Language Learning: A Literature Review” ( Chronological literature review about how the concept of listening skills has changed over time.)

You can also check out our templates with literature review examples and sample outlines at the links below.

Download Word doc Download Google doc

Before you begin searching for literature, you need a clearly defined topic .

If you are writing the literature review section of a dissertation or research paper, you will search for literature related to your research problem and questions .

Make a list of keywords

Start by creating a list of keywords related to your research question. Include each of the key concepts or variables you’re interested in, and list any synonyms and related terms. You can add to this list as you discover new keywords in the process of your literature search.

• Social media, Facebook, Instagram, Twitter, Snapchat, TikTok
• Body image, self-perception, self-esteem, mental health
• Generation Z, teenagers, adolescents, youth

Search for relevant sources

Use your keywords to begin searching for sources. Some useful databases to search for journals and articles include:

• Your university’s library catalogue
• Google Scholar
• Project Muse (humanities and social sciences)
• Medline (life sciences and biomedicine)
• EconLit (economics)
• Inspec (physics, engineering and computer science)

You can also use boolean operators to help narrow down your search.

Make sure to read the abstract to find out whether an article is relevant to your question. When you find a useful book or article, you can check the bibliography to find other relevant sources.

You likely won’t be able to read absolutely everything that has been written on your topic, so it will be necessary to evaluate which sources are most relevant to your research question.

For each publication, ask yourself:

• What question or problem is the author addressing?
• What are the key concepts and how are they defined?
• What are the key theories, models, and methods?
• Does the research use established frameworks or take an innovative approach?
• What are the results and conclusions of the study?
• How does the publication relate to other literature in the field? Does it confirm, add to, or challenge established knowledge?
• What are the strengths and weaknesses of the research?

Make sure the sources you use are credible , and make sure you read any landmark studies and major theories in your field of research.

You can use our template to summarize and evaluate sources you’re thinking about using. Click on either button below to download.

Take notes and cite your sources

As you read, you should also begin the writing process. Take notes that you can later incorporate into the text of your literature review.

It is important to keep track of your sources with citations to avoid plagiarism . It can be helpful to make an annotated bibliography , where you compile full citation information and write a paragraph of summary and analysis for each source. This helps you remember what you read and saves time later in the process.

The only proofreading tool specialized in correcting academic writing - try for free!

The academic proofreading tool has been trained on 1000s of academic texts and by native English editors. Making it the most accurate and reliable proofreading tool for students.

Try for free

To begin organizing your literature review’s argument and structure, be sure you understand the connections and relationships between the sources you’ve read. Based on your reading and notes, you can look for:

• Trends and patterns (in theory, method or results): do certain approaches become more or less popular over time?
• Themes: what questions or concepts recur across the literature?
• Debates, conflicts and contradictions: where do sources disagree?
• Pivotal publications: are there any influential theories or studies that changed the direction of the field?
• Gaps: what is missing from the literature? Are there weaknesses that need to be addressed?

This step will help you work out the structure of your literature review and (if applicable) show how your own research will contribute to existing knowledge.

• Most research has focused on young women.
• There is an increasing interest in the visual aspects of social media.
• But there is still a lack of robust research on highly visual platforms like Instagram and Snapchat—this is a gap that you could address in your own research.

There are various approaches to organizing the body of a literature review. Depending on the length of your literature review, you can combine several of these strategies (for example, your overall structure might be thematic, but each theme is discussed chronologically).

Chronological

The simplest approach is to trace the development of the topic over time. However, if you choose this strategy, be careful to avoid simply listing and summarizing sources in order.

Try to analyze patterns, turning points and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred.

If you have found some recurring central themes, you can organize your literature review into subsections that address different aspects of the topic.

For example, if you are reviewing literature about inequalities in migrant health outcomes, key themes might include healthcare policy, language barriers, cultural attitudes, legal status, and economic access.

Methodological

If you draw your sources from different disciplines or fields that use a variety of research methods , you might want to compare the results and conclusions that emerge from different approaches. For example:

• Look at what results have emerged in qualitative versus quantitative research
• Discuss how the topic has been approached by empirical versus theoretical scholarship
• Divide the literature into sociological, historical, and cultural sources

Theoretical

A literature review is often the foundation for a theoretical framework . You can use it to discuss various theories, models, and definitions of key concepts.

You might argue for the relevance of a specific theoretical approach, or combine various theoretical concepts to create a framework for your research.

Like any other academic text , your literature review should have an introduction , a main body, and a conclusion . What you include in each depends on the objective of your literature review.

The introduction should clearly establish the focus and purpose of the literature review.

Depending on the length of your literature review, you might want to divide the body into subsections. You can use a subheading for each theme, time period, or methodological approach.

As you write, you can follow these tips:

• Summarize and synthesize: give an overview of the main points of each source and combine them into a coherent whole
• Analyze and interpret: don’t just paraphrase other researchers — add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole
• Critically evaluate: mention the strengths and weaknesses of your sources
• Write in well-structured paragraphs: use transition words and topic sentences to draw connections, comparisons and contrasts

In the conclusion, you should summarize the key findings you have taken from the literature and emphasize their significance.

When you’ve finished writing and revising your literature review, don’t forget to proofread thoroughly before submitting. Not a language expert? Check out Scribbr’s professional proofreading services !

This article has been adapted into lecture slides that you can use to teach your students about writing a literature review.

Scribbr slides are free to use, customize, and distribute for educational purposes.

Open Google Slides Download PowerPoint

If you want to know more about the research process , methodology , research bias , or statistics , make sure to check out some of our other articles with explanations and examples.

• Sampling methods
• Simple random sampling
• Stratified sampling
• Cluster sampling
• Likert scales
• Reproducibility

 Statistics

• Null hypothesis
• Statistical power
• Probability distribution
• Effect size
• Poisson distribution

Research bias

• Optimism bias
• Cognitive bias
• Implicit bias
• Hawthorne effect
• Anchoring bias
• Explicit bias

A literature review is a survey of scholarly sources (such as books, journal articles, and theses) related to a specific topic or research question .

It is often written as part of a thesis, dissertation , or research paper , in order to situate your work in relation to existing knowledge.

There are several reasons to conduct a literature review at the beginning of a research project:

• To familiarize yourself with the current state of knowledge on your topic
• To ensure that you’re not just repeating what others have already done
• To identify gaps in knowledge and unresolved problems that your research can address
• To develop your theoretical framework and methodology
• To provide an overview of the key findings and debates on the topic

Writing the literature review shows your reader how your work relates to existing research and what new insights it will contribute.

The literature review usually comes near the beginning of your thesis or dissertation . After the introduction , it grounds your research in a scholarly field and leads directly to your theoretical framework or methodology .

A literature review is a survey of credible sources on a topic, often used in dissertations , theses, and research papers . Literature reviews give an overview of knowledge on a subject, helping you identify relevant theories and methods, as well as gaps in existing research. Literature reviews are set up similarly to other  academic texts , with an introduction , a main body, and a conclusion .

An  annotated bibliography is a list of  source references that has a short description (called an annotation ) for each of the sources. It is often assigned as part of the research process for a  paper .  

Cite this Scribbr article

If you want to cite this source, you can copy and paste the citation or click the “Cite this Scribbr article” button to automatically add the citation to our free Citation Generator.

McCombes, S. (2023, September 11). How to Write a Literature Review | Guide, Examples, & Templates. Scribbr. Retrieved April 15, 2024, from https://www.scribbr.com/dissertation/literature-review/

Is this article helpful?

Shona McCombes

Other students also liked, what is a theoretical framework | guide to organizing, what is a research methodology | steps & tips, how to write a research proposal | examples & templates, what is your plagiarism score.

How to write a literature review introduction (+ examples)

The introduction to a literature review serves as your reader’s guide through your academic work and thought process. Explore the significance of literature review introductions in review papers, academic papers, essays, theses, and dissertations. We delve into the purpose and necessity of these introductions, explore the essential components of literature review introductions, and provide step-by-step guidance on how to craft your own, along with examples.

Why you need an introduction for a literature review

When you need an introduction for a literature review, what to include in a literature review introduction, examples of literature review introductions, steps to write your own literature review introduction.

A literature review is a comprehensive examination of the international academic literature concerning a particular topic. It involves summarizing published works, theories, and concepts while also highlighting gaps and offering critical reflections.

In academic writing , the introduction for a literature review is an indispensable component. Effective academic writing requires proper paragraph structuring to guide your reader through your argumentation. This includes providing an introduction to your literature review.

It is imperative to remember that you should never start sharing your findings abruptly. Even if there isn’t a dedicated introduction section .

Instead, you should always offer some form of introduction to orient the reader and clarify what they can expect.

There are three main scenarios in which you need an introduction for a literature review:

• Academic literature review papers: When your literature review constitutes the entirety of an academic review paper, a more substantial introduction is necessary. This introduction should resemble the standard introduction found in regular academic papers.
• Literature review section in an academic paper or essay: While this section tends to be brief, it’s important to precede the detailed literature review with a few introductory sentences. This helps orient the reader before delving into the literature itself.
• Literature review chapter or section in your thesis/dissertation: Every thesis and dissertation includes a literature review component, which also requires a concise introduction to set the stage for the subsequent review.

You may also like: How to write a fantastic thesis introduction (+15 examples)

It is crucial to customize the content and depth of your literature review introduction according to the specific format of your academic work.

In practical terms, this implies, for instance, that the introduction in an academic literature review paper, especially one derived from a systematic literature review , is quite comprehensive. Particularly compared to the rather brief one or two introductory sentences that are often found at the beginning of a literature review section in a standard academic paper. The introduction to the literature review chapter in a thesis or dissertation again adheres to different standards.

Here’s a structured breakdown based on length and the necessary information:

Academic literature review paper

The introduction of an academic literature review paper, which does not rely on empirical data, often necessitates a more extensive introduction than the brief literature review introductions typically found in empirical papers. It should encompass:

• The research problem: Clearly articulate the problem or question that your literature review aims to address.
• The research gap: Highlight the existing gaps, limitations, or unresolved aspects within the current body of literature related to the research problem.
• The research relevance: Explain why the chosen research problem and its subsequent investigation through a literature review are significant and relevant in your academic field.
• The literature review method: If applicable, describe the methodology employed in your literature review, especially if it is a systematic review or follows a specific research framework.
• The main findings or insights of the literature review: Summarize the key discoveries, insights, or trends that have emerged from your comprehensive review of the literature.
• The main argument of the literature review: Conclude the introduction by outlining the primary argument or statement that your literature review will substantiate, linking it to the research problem and relevance you’ve established.
• Preview of the literature review’s structure: Offer a glimpse into the organization of the literature review paper, acting as a guide for the reader. This overview outlines the subsequent sections of the paper and provides an understanding of what to anticipate.

By addressing these elements, your introduction will provide a clear and structured overview of what readers can expect in your literature review paper.

Regular literature review section in an academic article or essay

Most academic articles or essays incorporate regular literature review sections, often placed after the introduction. These sections serve to establish a scholarly basis for the research or discussion within the paper.

In a standard 8000-word journal article, the literature review section typically spans between 750 and 1250 words. The first few sentences or the first paragraph within this section often serve as an introduction. It should encompass:

• An introduction to the topic: When delving into the academic literature on a specific topic, it’s important to provide a smooth transition that aids the reader in comprehending why certain aspects will be discussed within your literature review.
• The core argument: While literature review sections primarily synthesize the work of other scholars, they should consistently connect to your central argument. This central argument serves as the crux of your message or the key takeaway you want your readers to retain. By positioning it at the outset of the literature review section and systematically substantiating it with evidence, you not only enhance reader comprehension but also elevate overall readability. This primary argument can typically be distilled into 1-2 succinct sentences.

In some cases, you might include:

• Methodology: Details about the methodology used, but only if your literature review employed a specialized method. If your approach involved a broader overview without a systematic methodology, you can omit this section, thereby conserving word count.

By addressing these elements, your introduction will effectively integrate your literature review into the broader context of your academic paper or essay. This will, in turn, assist your reader in seamlessly following your overarching line of argumentation.

Introduction to a literature review chapter in thesis or dissertation

The literature review typically constitutes a distinct chapter within a thesis or dissertation. Often, it is Chapter 2 of a thesis or dissertation.

Some students choose to incorporate a brief introductory section at the beginning of each chapter, including the literature review chapter. Alternatively, others opt to seamlessly integrate the introduction into the initial sentences of the literature review itself. Both approaches are acceptable, provided that you incorporate the following elements:

• Purpose of the literature review and its relevance to the thesis/dissertation research: Explain the broader objectives of the literature review within the context of your research and how it contributes to your thesis or dissertation. Essentially, you’re telling the reader why this literature review is important and how it fits into the larger scope of your academic work.
• Primary argument: Succinctly communicate what you aim to prove, explain, or explore through the review of existing literature. This statement helps guide the reader’s understanding of the review’s purpose and what to expect from it.
• Preview of the literature review’s content: Provide a brief overview of the topics or themes that your literature review will cover. It’s like a roadmap for the reader, outlining the main areas of focus within the review. This preview can help the reader anticipate the structure and organization of your literature review.
• Methodology: If your literature review involved a specific research method, such as a systematic review or meta-analysis, you should briefly describe that methodology. However, this is not always necessary, especially if your literature review is more of a narrative synthesis without a distinct research method.

By addressing these elements, your introduction will empower your literature review to play a pivotal role in your thesis or dissertation research. It will accomplish this by integrating your research into the broader academic literature and providing a solid theoretical foundation for your work.

Comprehending the art of crafting your own literature review introduction becomes significantly more accessible when you have concrete examples to examine. Here, you will find several examples that meet, or in most cases, adhere to the criteria described earlier.

Example 1: An effective introduction for an academic literature review paper

To begin, let’s delve into the introduction of an academic literature review paper. We will examine the paper “How does culture influence innovation? A systematic literature review”, which was published in 2018 in the journal Management Decision.

The entire introduction spans 611 words and is divided into five paragraphs. In this introduction, the authors accomplish the following:

• In the first paragraph, the authors introduce the broader topic of the literature review, which focuses on innovation and its significance in the context of economic competition. They underscore the importance of this topic, highlighting its relevance for both researchers and policymakers.
• In the second paragraph, the authors narrow down their focus to emphasize the specific role of culture in relation to innovation.
• In the third paragraph, the authors identify research gaps, noting that existing studies are often fragmented and disconnected. They then emphasize the value of conducting a systematic literature review to enhance our understanding of the topic.
• In the fourth paragraph, the authors introduce their specific objectives and explain how their insights can benefit other researchers and business practitioners.
• In the fifth and final paragraph, the authors provide an overview of the paper’s organization and structure.

In summary, this introduction stands as a solid example. While the authors deviate from previewing their key findings (which is a common practice at least in the social sciences), they do effectively cover all the other previously mentioned points.

Example 2: An effective introduction to a literature review section in an academic paper

The second example represents a typical academic paper, encompassing not only a literature review section but also empirical data, a case study, and other elements. We will closely examine the introduction to the literature review section in the paper “The environmentalism of the subalterns: a case study of environmental activism in Eastern Kurdistan/Rojhelat”, which was published in 2021 in the journal Local Environment.

The paper begins with a general introduction and then proceeds to the literature review, designated by the authors as their conceptual framework. Of particular interest is the first paragraph of this conceptual framework, comprising 142 words across five sentences:

“ A peripheral and marginalised nationality within a multinational though-Persian dominated Iranian society, the Kurdish people of Iranian Kurdistan (a region referred by the Kurds as Rojhelat/Eastern Kurdi-stan) have since the early twentieth century been subject to multifaceted and systematic discriminatory and exclusionary state policy in Iran. This condition has left a population of 12–15 million Kurds in Iran suffering from structural inequalities, disenfranchisement and deprivation. Mismanagement of Kurdistan’s natural resources and the degradation of its natural environmental are among examples of this disenfranchisement. As asserted by Julian Agyeman (2005), structural inequalities that sustain the domination of political and economic elites often simultaneously result in environmental degradation, injustice and discrimination against subaltern communities. This study argues that the environmental struggle in Eastern Kurdistan can be asserted as a (sub)element of the Kurdish liberation movement in Iran. Conceptually this research is inspired by and has been conducted through the lens of ‘subalternity’ ” ( Hassaniyan, 2021, p. 931 ).

In this first paragraph, the author is doing the following:

• The author contextualises the research
• The author links the research focus to the international literature on structural inequalities
• The author clearly presents the argument of the research
• The author clarifies how the research is inspired by and uses the concept of ‘subalternity’.

Thus, the author successfully introduces the literature review, from which point onward it dives into the main concept (‘subalternity’) of the research, and reviews the literature on socio-economic justice and environmental degradation.

While introductions to a literature review section aren’t always required to offer the same level of study context detail as demonstrated here, this introduction serves as a commendable model for orienting the reader within the literature review. It effectively underscores the literature review’s significance within the context of the study being conducted.

Examples 3-5: Effective introductions to literature review chapters

The introduction to a literature review chapter can vary in length, depending largely on the overall length of the literature review chapter itself. For example, a master’s thesis typically features a more concise literature review, thus necessitating a shorter introduction. In contrast, a Ph.D. thesis, with its more extensive literature review, often includes a more detailed introduction.

Numerous universities offer online repositories where you can access theses and dissertations from previous years, serving as valuable sources of reference. Many of these repositories, however, may require you to log in through your university account. Nevertheless, a few open-access repositories are accessible to anyone, such as the one by the University of Manchester . It’s important to note though that copyright restrictions apply to these resources, just as they would with published papers.

Master’s thesis literature review introduction

The first example is “Benchmarking Asymmetrical Heating Models of Spider Pulsar Companions” by P. Sun, a master’s thesis completed at the University of Manchester on January 9, 2024. The author, P. Sun, introduces the literature review chapter very briefly but effectively:

PhD thesis literature review chapter introduction

The second example is Deep Learning on Semi-Structured Data and its Applications to Video-Game AI, Woof, W. (Author). 31 Dec 2020, a PhD thesis completed at the University of Manchester . In Chapter 2, the author offers a comprehensive introduction to the topic in four paragraphs, with the final paragraph serving as an overview of the chapter’s structure:

PhD thesis literature review introduction

The last example is the doctoral thesis Metacognitive strategies and beliefs: Child correlates and early experiences Chan, K. Y. M. (Author). 31 Dec 2020 . The author clearly conducted a systematic literature review, commencing the review section with a discussion of the methodology and approach employed in locating and analyzing the selected records.

Having absorbed all of this information, let’s recap the essential steps and offer a succinct guide on how to proceed with creating your literature review introduction:

• Contextualize your review : Begin by clearly identifying the academic context in which your literature review resides and determining the necessary information to include.
• Outline your structure : Develop a structured outline for your literature review, highlighting the essential information you plan to incorporate in your introduction.
• Literature review process : Conduct a rigorous literature review, reviewing and analyzing relevant sources.
• Summarize and abstract : After completing the review, synthesize the findings and abstract key insights, trends, and knowledge gaps from the literature.
• Craft the introduction : Write your literature review introduction with meticulous attention to the seamless integration of your review into the larger context of your work. Ensure that your introduction effectively elucidates your rationale for the chosen review topics and the underlying reasons guiding your selection.

Get new content delivered directly to your inbox!

Subscribe and receive Master Academia's quarterly newsletter.

The best answers to "What are your plans for the future?"

10 tips for engaging your audience in academic writing, related articles.

How to peer review an academic paper

PhD thesis types: Monograph and collection of articles

How to disagree with reviewers (with examples!)

How to introduce yourself in a conference presentation (in six simple steps)

How To Structure Your Literature Review

3 options to help structure your chapter.

By: Amy Rommelspacher (PhD) | Reviewer: Dr Eunice Rautenbach | November 2020 (Updated May 2023)

Writing the literature review chapter can seem pretty daunting when you’re piecing together your dissertation or thesis. As  we’ve discussed before , a good literature review needs to achieve a few very important objectives – it should:

• Demonstrate your knowledge of the research topic
• Identify the gaps in the literature and show how your research links to these
• Provide the foundation for your conceptual framework (if you have one)
• Inform your own  methodology and research design

To achieve this, your literature review needs a well-thought-out structure . Get the structure of your literature review chapter wrong and you’ll struggle to achieve these objectives. Don’t worry though – in this post, we’ll look at how to structure your literature review for maximum impact (and marks!).

But wait – is this the right time?

Deciding on the structure of your literature review should come towards the end of the literature review process – after you have collected and digested the literature, but before you start writing the chapter. 

In other words, you need to first develop a rich understanding of the literature before you even attempt to map out a structure. There’s no use trying to develop a structure before you’ve fully wrapped your head around the existing research.

Equally importantly, you need to have a structure in place before you start writing , or your literature review will most likely end up a rambling, disjointed mess. 

Importantly, don’t feel that once you’ve defined a structure you can’t iterate on it. It’s perfectly natural to adjust as you engage in the writing process. As we’ve discussed before , writing is a way of developing your thinking, so it’s quite common for your thinking to change – and therefore, for your chapter structure to change – as you write. 

Need a helping hand?

Like any other chapter in your thesis or dissertation, your literature review needs to have a clear, logical structure. At a minimum, it should have three essential components – an  introduction , a  body   and a  conclusion . 

Let’s take a closer look at each of these.

1: The Introduction Section

Just like any good introduction, the introduction section of your literature review should introduce the purpose and layout (organisation) of the chapter. In other words, your introduction needs to give the reader a taste of what’s to come, and how you’re going to lay that out. Essentially, you should provide the reader with a high-level roadmap of your chapter to give them a taste of the journey that lies ahead.

Here’s an example of the layout visualised in a literature review introduction:

Your introduction should also outline your topic (including any tricky terminology or jargon) and provide an explanation of the scope of your literature review – in other words, what you  will   and  won’t   be covering (the delimitations ). This helps ringfence your review and achieve a clear focus . The clearer and narrower your focus, the deeper you can dive into the topic (which is typically where the magic lies). 

Depending on the nature of your project, you could also present your stance or point of view at this stage. In other words, after grappling with the literature you’ll have an opinion about what the trends and concerns are in the field as well as what’s lacking. The introduction section can then present these ideas so that it is clear to examiners that you’re aware of how your research connects with existing knowledge .

2: The Body Section

The body of your literature review is the centre of your work. This is where you’ll present, analyse, evaluate and synthesise the existing research. In other words, this is where you’re going to earn (or lose) the most marks. Therefore, it’s important to carefully think about how you will organise your discussion to present it in a clear way. 

The body of your literature review should do just as the description of this chapter suggests. It should “review” the literature – in other words, identify, analyse, and synthesise it. So, when thinking about structuring your literature review, you need to think about which structural approach will provide the best “review” for your specific type of research and objectives (we’ll get to this shortly).

There are (broadly speaking)  three options  for organising your literature review.

Option 1: Chronological (according to date)

Organising the literature chronologically is one of the simplest ways to structure your literature review. You start with what was published first and work your way through the literature until you reach the work published most recently. Pretty straightforward.

The benefit of this option is that it makes it easy to discuss the developments and debates in the field as they emerged over time. Organising your literature chronologically also allows you to highlight how specific articles or pieces of work might have changed the course of the field – in other words, which research has had the most impact . Therefore, this approach is very useful when your research is aimed at understanding how the topic has unfolded over time and is often used by scholars in the field of history. That said, this approach can be utilised by anyone that wants to explore change over time .

For example , if a student of politics is investigating how the understanding of democracy has evolved over time, they could use the chronological approach to provide a narrative that demonstrates how this understanding has changed through the ages.

Here are some questions you can ask yourself to help you structure your literature review chronologically.

• What is the earliest literature published relating to this topic?
• How has the field changed over time? Why?
• What are the most recent discoveries/theories?

In some ways, chronology plays a part whichever way you decide to structure your literature review, because you will always, to a certain extent, be analysing how the literature has developed. However, with the chronological approach, the emphasis is very firmly on how the discussion has evolved over time , as opposed to how all the literature links together (which we’ll discuss next ).

Option 2: Thematic (grouped by theme)

The thematic approach to structuring a literature review means organising your literature by theme or category – for example, by independent variables (i.e. factors that have an impact on a specific outcome).

As you’ve been collecting and synthesising literature , you’ll likely have started seeing some themes or patterns emerging. You can then use these themes or patterns as a structure for your body discussion. The thematic approach is the most common approach and is useful for structuring literature reviews in most fields.

For example, if you were researching which factors contributed towards people trusting an organisation, you might find themes such as consumers’ perceptions of an organisation’s competence, benevolence and integrity. Structuring your literature review thematically would mean structuring your literature review’s body section to discuss each of these themes, one section at a time.

Here are some questions to ask yourself when structuring your literature review by themes:

• Are there any patterns that have come to light in the literature?
• What are the central themes and categories used by the researchers?
• Do I have enough evidence of these themes?

PS – you can see an example of a thematically structured literature review in our literature review sample walkthrough video here.

Option 3: Methodological

The methodological option is a way of structuring your literature review by the research methodologies used . In other words, organising your discussion based on the angle from which each piece of research was approached – for example, qualitative , quantitative or mixed  methodologies.

Structuring your literature review by methodology can be useful if you are drawing research from a variety of disciplines and are critiquing different methodologies. The point of this approach is to question  how  existing research has been conducted, as opposed to  what  the conclusions and/or findings the research were.

For example, a sociologist might centre their research around critiquing specific fieldwork practices. Their literature review will then be a summary of the fieldwork methodologies used by different studies.

Here are some questions you can ask yourself when structuring your literature review according to methodology:

• Which methodologies have been utilised in this field?
• Which methodology is the most popular (and why)?
• What are the strengths and weaknesses of the various methodologies?
• How can the existing methodologies inform my own methodology?

3: The Conclusion Section

Once you’ve completed the body section of your literature review using one of the structural approaches we discussed above, you’ll need to “wrap up” your literature review and pull all the pieces together to set the direction for the rest of your dissertation or thesis.

The conclusion is where you’ll present the key findings of your literature review. In this section, you should emphasise the research that is especially important to your research questions and highlight the gaps that exist in the literature. Based on this, you need to make it clear what you will add to the literature – in other words, justify your own research by showing how it will help fill one or more of the gaps you just identified.

Last but not least, if it’s your intention to develop a conceptual framework for your dissertation or thesis, the conclusion section is a good place to present this.

Example: Thematically Structured Review

In the video below, we unpack a literature review chapter so that you can see an example of a thematically structure review in practice.

Let’s Recap

In this article, we’ve  discussed how to structure your literature review for maximum impact. Here’s a quick recap of what  you need to keep in mind when deciding on your literature review structure:

• Just like other chapters, your literature review needs a clear introduction , body and conclusion .
• The introduction section should provide an overview of what you will discuss in your literature review.
• The body section of your literature review can be organised by chronology , theme or methodology . The right structural approach depends on what you’re trying to achieve with your research.
• The conclusion section should draw together the key findings of your literature review and link them to your research questions.

If you’re ready to get started, be sure to download our free literature review template to fast-track your chapter outline.

Psst… there’s more!

This post is an extract from our bestselling Udemy Course, Literature Review Bootcamp . If you want to work smart, you don't want to miss this .

You Might Also Like:

27 Comments

Great work. This is exactly what I was looking for and helps a lot together with your previous post on literature review. One last thing is missing: a link to a great literature chapter of an journal article (maybe with comments of the different sections in this review chapter). Do you know any great literature review chapters?

I agree with you Marin… A great piece

I agree with Marin. This would be quite helpful if you annotate a nicely structured literature from previously published research articles.

Awesome article for my research.

I thank you immensely for this wonderful guide

It is indeed thought and supportive work for the futurist researcher and students

Very educative and good time to get guide. Thank you

Great work, very insightful. Thank you.

Thanks for this wonderful presentation. My question is that do I put all the variables into a single conceptual framework or each hypothesis will have it own conceptual framework?

Thank you very much, very helpful

This is very educative and precise . Thank you very much for dropping this kind of write up .

Pheeww, so damn helpful, thank you for this informative piece.

I’m doing a research project topic ; stool analysis for parasitic worm (enteric) worm, how do I structure it, thanks.

comprehensive explanation. Help us by pasting the URL of some good “literature review” for better understanding.

great piece. thanks for the awesome explanation. it is really worth sharing. I have a little question, if anyone can help me out, which of the options in the body of literature can be best fit if you are writing an architectural thesis that deals with design?

I am doing a research on nanofluids how can l structure it?

Beautifully clear.nThank you!

Lucid! Thankyou!

Brilliant work, well understood, many thanks

I like how this was so clear with simple language 😊😊 thank you so much 😊 for these information 😊

Insightful. I was struggling to come up with a sensible literature review but this has been really helpful. Thank you!

You have given thought-provoking information about the review of the literature.

Thank you. It has made my own research better and to impart your work to students I teach

I learnt a lot from this teaching. It’s a great piece.

I am doing research on EFL teacher motivation for his/her job. How Can I structure it? Is there any detailed template, additional to this?

You are so cool! I do not think I’ve read through something like this before. So nice to find somebody with some genuine thoughts on this issue. Seriously.. thank you for starting this up. This site is one thing that is required on the internet, someone with a little originality!

I’m asked to do conceptual, theoretical and empirical literature, and i just don’t know how to structure it

Submit a Comment Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

• Print Friendly

Literature Reviews

• Overview of Literature Reviews and Systematic Reviews
• How to Get Started and Developing a Research Question
• Finding and Evaluating Sources
• Citations This link opens in a new window
• Synthesizing Sources
• Writing the Literature Review
• Systematic Reviews This link opens in a new window
• Suggested Readings
• Elements of a Literature Review
• Introduction
• Reference List

All literature reviews contain the following elements:

See the tabs to right for further explanation of each of these elements.

The introduction to a literature review should include the following:

• Define the topic to provide context for the review
• Identify trends in previous publications
• Give your reasoning for reviewing the literature (Why is it necessary? What is your point of view?)
• Explain the criteria that was used to conduct the search
• Indicate how the review is organized

The body of the literature review will discuss each source. Find patterns and ways to tie the main points together. This can be organized thematically, chronologically, or methodologically.

Thematic-organized around a topic or issue

Chronological-organized according to when the articles were published or according to when trends took place

Methodological-organized by the methods used by the researchers

The conclusion should summarize the literature review. Discuss any implications drawn from the literature and what further research is needed.

A reference list at the end of a literature review is essential. Citing all sources gives credit to the authors of the literature, allows others to find the literature for evaluation or their own research, and helps to avoid plagiarism. For more information on creating a reference list, see our Citation Styles guide.

Adding Content & Organizing the Review

The literature review is about both content and form.  In terms of content, keep in mind that your literature review is intended to:

• Set up a theoretical framework for your own research
• Show a clear understanding of the key concepts/ideas/studies/models related to your topic
• Demonstrate knowledge about the history of your research area and any related controversies
• Illustrate that you are able to evaluate and synthesize the work of others
• Clarify significant definitions and terminology
• Develop a space in your discipline for your research

Some questions to ask yourself when you begin to write your first draft include:

• How will my literature review be organized: Chronologically, thematically, conceptually, methodologically or a combination?
• What section headings will I be using?
• How do the various studies relate to each other?
• What contributions do they make to the field?
• What are the limitations of a study/where are the gaps in the research?
• And finally but most importantly, how does my own research fit into what has already been done?

Some questions to ask after the first draft:

• Is there a logical flow from section to section, paragraph to paragraph, sentence to sentence?
• Does the content proceed from topic to topic?
• Does your conclusion match your introduction?
• Were you consistent in documenting and using the correct citation style?

Attribution

The content of this page was developed from Chapter 8, "Writing a Literature Review" in:

Frederiksen, L., & Phelps, S. F. (2017). Literature reviews for education and nursing graduate students. Rebus Community.  https://open.umn.edu/opentextbooks/textbooks/literature-reviews-for-education-and-nursing-graduate-students

• << Previous: Synthesizing Sources
• Next: Systematic Reviews >>
• Last Updated: Nov 30, 2023 1:07 PM
• URL: https://libguides.chapman.edu/literature_reviews

Have a language expert improve your writing

Run a free plagiarism check in 10 minutes, automatically generate references for free.

• Knowledge Base
• Dissertation
• What is a Literature Review? | Guide, Template, & Examples

What is a Literature Review? | Guide, Template, & Examples

Published on 22 February 2022 by Shona McCombes . Revised on 7 June 2022.

What is a literature review? A literature review is a survey of scholarly sources on a specific topic. It provides an overview of current knowledge, allowing you to identify relevant theories, methods, and gaps in the existing research.

There are five key steps to writing a literature review:

• Search for relevant literature
• Evaluate sources
• Identify themes, debates and gaps
• Outline the structure
• Write your literature review

A good literature review doesn’t just summarise sources – it analyses, synthesises, and critically evaluates to give a clear picture of the state of knowledge on the subject.

Instantly correct all language mistakes in your text

Be assured that you'll submit flawless writing. Upload your document to correct all your mistakes.

Table of contents

Why write a literature review, examples of literature reviews, step 1: search for relevant literature, step 2: evaluate and select sources, step 3: identify themes, debates and gaps, step 4: outline your literature review’s structure, step 5: write your literature review, frequently asked questions about literature reviews, introduction.

• Quick Run-through
• Step 1 & 2

When you write a dissertation or thesis, you will have to conduct a literature review to situate your research within existing knowledge. The literature review gives you a chance to:

• Demonstrate your familiarity with the topic and scholarly context
• Develop a theoretical framework and methodology for your research
• Position yourself in relation to other researchers and theorists
• Show how your dissertation addresses a gap or contributes to a debate

You might also have to write a literature review as a stand-alone assignment. In this case, the purpose is to evaluate the current state of research and demonstrate your knowledge of scholarly debates around a topic.

The content will look slightly different in each case, but the process of conducting a literature review follows the same steps. We’ve written a step-by-step guide that you can follow below.

Prevent plagiarism, run a free check.

Writing literature reviews can be quite challenging! A good starting point could be to look at some examples, depending on what kind of literature review you’d like to write.

• Example literature review #1: “Why Do People Migrate? A Review of the Theoretical Literature” ( Theoretical literature review about the development of economic migration theory from the 1950s to today.)
• Example literature review #2: “Literature review as a research methodology: An overview and guidelines” ( Methodological literature review about interdisciplinary knowledge acquisition and production.)
• Example literature review #3: “The Use of Technology in English Language Learning: A Literature Review” ( Thematic literature review about the effects of technology on language acquisition.)
• Example literature review #4: “Learners’ Listening Comprehension Difficulties in English Language Learning: A Literature Review” ( Chronological literature review about how the concept of listening skills has changed over time.)

You can also check out our templates with literature review examples and sample outlines at the links below.

Download Word doc Download Google doc

Before you begin searching for literature, you need a clearly defined topic .

If you are writing the literature review section of a dissertation or research paper, you will search for literature related to your research objectives and questions .

If you are writing a literature review as a stand-alone assignment, you will have to choose a focus and develop a central question to direct your search. Unlike a dissertation research question, this question has to be answerable without collecting original data. You should be able to answer it based only on a review of existing publications.

Make a list of keywords

Start by creating a list of keywords related to your research topic. Include each of the key concepts or variables you’re interested in, and list any synonyms and related terms. You can add to this list if you discover new keywords in the process of your literature search.

• Social media, Facebook, Instagram, Twitter, Snapchat, TikTok
• Body image, self-perception, self-esteem, mental health
• Generation Z, teenagers, adolescents, youth

Search for relevant sources

Use your keywords to begin searching for sources. Some databases to search for journals and articles include:

• Your university’s library catalogue
• Google Scholar
• Project Muse (humanities and social sciences)
• Medline (life sciences and biomedicine)
• EconLit (economics)
• Inspec (physics, engineering and computer science)

You can use boolean operators to help narrow down your search:

Read the abstract to find out whether an article is relevant to your question. When you find a useful book or article, you can check the bibliography to find other relevant sources.

To identify the most important publications on your topic, take note of recurring citations. If the same authors, books or articles keep appearing in your reading, make sure to seek them out.

You probably won’t be able to read absolutely everything that has been written on the topic – you’ll have to evaluate which sources are most relevant to your questions.

For each publication, ask yourself:

• What question or problem is the author addressing?
• What are the key concepts and how are they defined?
• What are the key theories, models and methods? Does the research use established frameworks or take an innovative approach?
• What are the results and conclusions of the study?
• How does the publication relate to other literature in the field? Does it confirm, add to, or challenge established knowledge?
• How does the publication contribute to your understanding of the topic? What are its key insights and arguments?
• What are the strengths and weaknesses of the research?

Make sure the sources you use are credible, and make sure you read any landmark studies and major theories in your field of research.

You can find out how many times an article has been cited on Google Scholar – a high citation count means the article has been influential in the field, and should certainly be included in your literature review.

The scope of your review will depend on your topic and discipline: in the sciences you usually only review recent literature, but in the humanities you might take a long historical perspective (for example, to trace how a concept has changed in meaning over time).

Remember that you can use our template to summarise and evaluate sources you’re thinking about using!

Take notes and cite your sources

As you read, you should also begin the writing process. Take notes that you can later incorporate into the text of your literature review.

It’s important to keep track of your sources with references to avoid plagiarism . It can be helpful to make an annotated bibliography, where you compile full reference information and write a paragraph of summary and analysis for each source. This helps you remember what you read and saves time later in the process.

You can use our free APA Reference Generator for quick, correct, consistent citations.

To begin organising your literature review’s argument and structure, you need to understand the connections and relationships between the sources you’ve read. Based on your reading and notes, you can look for:

• Trends and patterns (in theory, method or results): do certain approaches become more or less popular over time?
• Themes: what questions or concepts recur across the literature?
• Debates, conflicts and contradictions: where do sources disagree?
• Pivotal publications: are there any influential theories or studies that changed the direction of the field?
• Gaps: what is missing from the literature? Are there weaknesses that need to be addressed?

This step will help you work out the structure of your literature review and (if applicable) show how your own research will contribute to existing knowledge.

• Most research has focused on young women.
• There is an increasing interest in the visual aspects of social media.
• But there is still a lack of robust research on highly-visual platforms like Instagram and Snapchat – this is a gap that you could address in your own research.

There are various approaches to organising the body of a literature review. You should have a rough idea of your strategy before you start writing.

Depending on the length of your literature review, you can combine several of these strategies (for example, your overall structure might be thematic, but each theme is discussed chronologically).

Chronological

The simplest approach is to trace the development of the topic over time. However, if you choose this strategy, be careful to avoid simply listing and summarising sources in order.

Try to analyse patterns, turning points and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred.

If you have found some recurring central themes, you can organise your literature review into subsections that address different aspects of the topic.

For example, if you are reviewing literature about inequalities in migrant health outcomes, key themes might include healthcare policy, language barriers, cultural attitudes, legal status, and economic access.

Methodological

If you draw your sources from different disciplines or fields that use a variety of research methods , you might want to compare the results and conclusions that emerge from different approaches. For example:

• Look at what results have emerged in qualitative versus quantitative research
• Discuss how the topic has been approached by empirical versus theoretical scholarship
• Divide the literature into sociological, historical, and cultural sources

Theoretical

A literature review is often the foundation for a theoretical framework . You can use it to discuss various theories, models, and definitions of key concepts.

You might argue for the relevance of a specific theoretical approach, or combine various theoretical concepts to create a framework for your research.

Like any other academic text, your literature review should have an introduction , a main body, and a conclusion . What you include in each depends on the objective of your literature review.

The introduction should clearly establish the focus and purpose of the literature review.

If you are writing the literature review as part of your dissertation or thesis, reiterate your central problem or research question and give a brief summary of the scholarly context. You can emphasise the timeliness of the topic (“many recent studies have focused on the problem of x”) or highlight a gap in the literature (“while there has been much research on x, few researchers have taken y into consideration”).

Depending on the length of your literature review, you might want to divide the body into subsections. You can use a subheading for each theme, time period, or methodological approach.

As you write, make sure to follow these tips:

• Summarise and synthesise: give an overview of the main points of each source and combine them into a coherent whole.
• Analyse and interpret: don’t just paraphrase other researchers – add your own interpretations, discussing the significance of findings in relation to the literature as a whole.
• Critically evaluate: mention the strengths and weaknesses of your sources.
• Write in well-structured paragraphs: use transitions and topic sentences to draw connections, comparisons and contrasts.

In the conclusion, you should summarise the key findings you have taken from the literature and emphasise their significance.

If the literature review is part of your dissertation or thesis, reiterate how your research addresses gaps and contributes new knowledge, or discuss how you have drawn on existing theories and methods to build a framework for your research. This can lead directly into your methodology section.

A literature review is a survey of scholarly sources (such as books, journal articles, and theses) related to a specific topic or research question .

It is often written as part of a dissertation , thesis, research paper , or proposal .

There are several reasons to conduct a literature review at the beginning of a research project:

• To familiarise yourself with the current state of knowledge on your topic
• To ensure that you’re not just repeating what others have already done
• To identify gaps in knowledge and unresolved problems that your research can address
• To develop your theoretical framework and methodology
• To provide an overview of the key findings and debates on the topic

Writing the literature review shows your reader how your work relates to existing research and what new insights it will contribute.

The literature review usually comes near the beginning of your  dissertation . After the introduction , it grounds your research in a scholarly field and leads directly to your theoretical framework or methodology .

Cite this Scribbr article

If you want to cite this source, you can copy and paste the citation or click the ‘Cite this Scribbr article’ button to automatically add the citation to our free Reference Generator.

McCombes, S. (2022, June 07). What is a Literature Review? | Guide, Template, & Examples. Scribbr. Retrieved 15 April 2024, from https://www.scribbr.co.uk/thesis-dissertation/literature-review/

Is this article helpful?

Shona McCombes

Other students also liked, how to write a dissertation proposal | a step-by-step guide, what is a theoretical framework | a step-by-step guide, what is a research methodology | steps & tips.

Writing Literature Reviews: 4. Structure Your Lit Review

• What is a "Literature Review"?
• 1. Brainstorm
• 3. Refine Search and Topic
• 4. Structure Your Lit Review
• Helpful Sites

How to Structure Your Lit Review

A literature review, even when it is within a larger paper, should include an introduction, a main body section, and a conclusion.

In the Introduction Section :

• define your topic and scope
• explain the organization of your lit review

In the Main Section :

• Present the literature you found related to your topic in a clear, organized way
• Compare and contrast the literature
• Identify problems, issues, and debates among scholars on the topic

There are many ways to organize the main section of a literature review. Here are a few ways you could organize this section:

• Chronological - Present a condensed history of the major ideas and developments of a topic over time.
• Thematic - Present the major theories relevant to your topic and how they agree or contrast.
• Methodological - If there are different methods of research on your topic, you can organize your review by grouping the findings of different methodologies. Be sure to compare and contrast these methods (you are setting up an argument for your own methods.)
• Theoretical - Organize your review by the various theories others have developed relevant to the topic, comparing and contrasting the strengths and weaknesses of each.

In the Conclusion Section :

• Summarize your findings in the scholarly literature
• Identify any gaps and explain briefly how you are filling that gap with your own research (if appropriate)
• Explain how your paper/ideas/research relates to the greater scholarly literature and create a transition to the rest of your paper

Helpful Sites on Literature Reviews

Much of the information in this guide and more information can be found on the websites listed on the  Helpful Sites tab .

Ask A Librarian

Make an appointment

Chat with a Librarian

Email [email protected]

• << Previous: 3. Refine Search and Topic
• Next: Tools >>
• University of Colorado Boulder Libraries
• Research Guides
• Writing Literature Reviews
• Last Updated: Feb 29, 2024 3:43 PM
• URL: https://libguides.colorado.edu/litreview

• Essay Guide
• Alex Essay Writing Tool
• Dissertation Guide
• Ask The Elephant

The structure of a literature review

A literature review should be structured like any other essay: it should have an introduction, a middle or main body, and a conclusion.

Introduction

The introduction should:

• define your topic and provide an appropriate context for reviewing the literature;
• establish your reasons – i.e. point of view – for
• reviewing the literature;
• explain the organisation – i.e. sequence – of the review;
• state the scope of the review – i.e. what is included and what isn’t included. For example, if you were reviewing the literature on obesity in children you might say something like: There are a large number of studies of obesity trends in the general population. However, since the focus of this research is on obesity in children, these will not be reviewed in detail and will only be referred to as appropriate.

The middle or main body should:

• organise the literature according to common themes;
• provide insight into the relation between your chosen topic and the wider subject area e.g. between obesity in children and obesity in general;
• move from a general, wider view of the literature being reviewed to the specific focus of your research.

The conclusion should:

• summarise the important aspects of the existing body of literature;
• evaluate the current state of the literature reviewed;
• identify significant flaws or gaps in existing knowledge;
• outline areas for future study;
• link your research to existing knowledge.

Privacy Overview

Want to create or adapt books like this? Learn more about how Pressbooks supports open publishing practices.

The literature review structure and function

Part 4: Chapter 14

Questions to consider

A. Why is a literature review also referred to as the background or introduction of a paper?

B. What are the functions of a literature review?

C. What is the primary objective of a literature review?

No matter how the literature review is organized (e.g. chronologically, thematically), it follows a standard format: introduction, body, conclusion.  The introduction to the literature review contains a statement or statements about the overall topic of consideration. This might be a paragraph or section that lets the reader know what the literature review will address. Occasionally, writers describe how the literature review will be organized (for example, what main points are going to be dealt with and in what order). Like a methods section, search criteria (keywords, databases, journals) are sometimes identified this section; they may be discussed in the conclusion as well or not attended to.

An introduction to an introduction

The purpose of the introduction to the literature review is to lead the reader through the body and the main points to the ultimate message of the work. The introduction will achieve several goals.

• Define or identify the general topic, issue, or area of concern thereby providing an appropriate context and a historical frame of reference for the remainder of the review.
• Indicate overall trends in what has been previously published on the topic; refer to a landmark or seminal study; or reveal conflicts in theory, methodology, evidence, conclusions, or gaps in research and scholarship.
• Establish the objective for reviewing this research (point of view); explain the criteria used to select the reviewed material; the organization of the review (sequence); and – if necessary – why certain literature either is or is not included (scope).
• Demonstrate how ensuing research either closes a gap in the literature, extends earlier work, or replicates an important study thereby contributing new knowledge to the field.

The body of the literature review

Written information is commonly presented logically, from general to specific, showing how past research relates to a proposed project (for literature reviews that serve as the background or introduction to a research proposal or paper).  Information should be deliberately organized following an obvious progression of ideas (e.g. chronologically, following the development of a research topic) with consistent support from acceptable sources.

This is where a strong synthesis works to illustrate the value of the writer’s contribution and to persuade the reader. To that end, citing two or more sources for a single point demonstrates its strength or general acceptability.

The use of a formal academic voice should be consistently maintained, and the content should be  focused and objective. Author contribution should illustrate important strengths and weaknesses of research studies as well as contradictions and inconsistent findings. Implications and suggestions for further research, or where there are gaps in the current literature, should be specific, original and a logical conclusion based on the sources deployed as evidence.

Strong conclusions

The conclusion often summarizes the major points of the literature review, discusses implications, and reveals an area for future or further research needed. This is where the proportion of writer contribution is often higher and there is relatively less cited source material.

The conclusion will often

• clearly define the topic or issue for an informed audience;
• provide a complete and exhaustive overview of relevant literature;
• be focused throughout;
• critically and consistently evaluate and synthesize extant information;
• present information logically and accurately;
• be relevant and objective; and
• accurately cite all references using one citation style or system.

Documenting the support

The reference list of publications used in a literature review serves two purposes. First, it provides the reader with a means to evaluate the quality of the research. Second, accurately and correctly citing all the sources used protects the author from possible accusations of plagiarism. Using the words or ideas of others without referencing the source is a very serious academic offense.

The reference list reflects the thoroughness of the review. It also allows others to retrieve the cited publications. Errors made in authors’ names, journal or article titles, page numbers and dates present barriers to retrieval of articles and prevent attributing credit to authors for their work. Each reference should be checked carefully for errors. Every in-text citation must have a listing in the references and every title in the reference list should connect to an in-text citation. [1]

Exercise #1

Read the following brief literature review from Attending lectures in person, hybrid or online—how do students choose, and what about the outcome? and complete an simple inventory of it by answering these questions:

• What is the topic and how is it relevant?
• How many unique sources are used?
• How many citations are there?
• What ideas do the authors contribute on this topic?
• What can readers expect from the rest of the article?

Introduction 1 The COVID-19 pandemic has occasionally been viewed as one of the biggest experiments in education (Tomas & Rogers, 2020; Dunrong & Jin, 2020).  2 This might be a misnomer, since “experiment” implies some sort of controlled conditions, while arguably, educational settings were largely controlled by fluctuating, external factors.  3 “Disruption” might be a more fitting characterization of what was essentially an emergency response, and in the aftermath of this disruption, increased flexibility in attendance and delivery modes of education will become the “new normal” (Kortemeyer, 2020; Schapiro, 2021; Hofer et al., 2021). 4 The educational experiment starts now, as the impact of this flexibility can be investigated in more controlled settings. 5 A preliminary “finding” of this experiment is that many faculty members report that live-lecture attendance has decreased—some faculty members even go so far as to demand that streaming, video conferencing, and recording should be discontinued, “now that the pandemic is over,” to force students to return to campus. 6 There might be some justification for that: both students and faculty who knew the university before COVID-19 bemoan the loss of campus culture, and there are certainly cross-disciplinary and social competencies that were implicit in higher education, such as scientific discourse, self-presentation, teamwork, conflict resolution, etc., which may not be fostered anymore when purely focusing on the explicit curriculum of teaching and transmitting facts, methods, and concepts. 7 There are also serious concerns about loneliness, depression, anxiety, and procrastination that need to be addressed (Wang et al., 2020; Pelikan et al., 2021; Copeland et al., 2021; Tasso et al., 2021; Amendola et al., 2021; Buizza et al., 2022), which are consistent with a survey on student well-being conducted at ETH Zurich at the height of the pandemic. 8 The problems and their solutions are likely more complex and reaching deeper—the pandemic may have simply brought some existing inconsistencies in the 21st-century higher-education system to the surface, particularly when it comes to lecturing (Vlachopoulos & Jan, 2020). 9 An immediate question is how student choices regarding attendance may have influenced performance in the subsequent exam session. 10 Finally, throughout the whole pandemic, high-stake exams were conducted in-person on-site at ETH Zurich, and another question is how the students’ perception of these physical exam settings may be connected to their potentially completely virtual attendance during the learning phase. [2]

Review and Reinforce

The goal of the literature review is to present an argument defending the relevance and value of a research question. To that end, a literature review must be balanced. For example, in proposing a new theory, both findings that are consistent with that theory and contradictory evidence must be discussed. It is acceptable to argue that the balance of the research supports the existence of a phenomenon or is consistent with a theory, but it is not acceptable to ignore contradictory evidence. What makes a research question interesting is often the uncertainty about its answer.

Media Attributions

• activist art © Ron Cogswell is licensed under a CC BY (Attribution) license
• Adapted from Frederiksen, L., & Phelps, S. F. (2017). Literature Reviews for Education and Nursing Graduate Students. Open Textbook Library. ↵
• Kortemeyer, G., Dittmann-Domenichini, N., Schlienger, C., Spilling, E., Yaroshchuk, A., & Dissertori, G. (2023). Attending lectures in person, hybrid or online—how do students choose, and what about the outcome?: Revista de Universidad y Sociedad del Conocimiento. International Journal of Educational Technology in Higher Education , 20(1), 19. https://doi.org/10.1186/s41239-023-00387-5. ↵

Sourcing, summarizing, and synthesizing:  Skills for effective research writing  Copyright © 2023 by Wendy L. McBride is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

Share This Book

Writing a Literature Review

• What is a Literature Review?
• Step 1: Choosing a Topic
• Step 2: Finding Information
• Step 3: Evaluating Content
• Step 4: Taking Notes
• Step 5: Synthesizing Content
• Step 6: Writing the Review
• Step 7: Citing Your Sources
• Meet the Library Team
• Off-Campus & Mobile Access
• Research Help
• Other Helpful Guides

Writing the Review

You've done the research and now your ready to put your findings down on paper. When preparing to write your review, first consider how will you organize your review.

The actual review generally has 5 components:

• Introduction
• Bibliography

A good literature review shows signs of synthesis and understanding of the topic. There should be strong evidence of analytical thinking as illustrated through the connections you make between the literature being reviewed. Think of it this way- a literature review is much more than a book review. It is a document where you present your sources and their overall relationship to your thesis statement.

Conversly, a poor literature review will simply list and identify the sources . In essence, it will appear to be a glorifed annotated bibliography.

• Literature Reviews: The University of North Carolina http://writingcenter.unc.edu/handouts/literature-reviews/
• Writing a Literature Review: Wesleyan University
• Literature Review Tip Sheet: Edith Cowan University See additional information, including other tip sheets at http://intranet.ecu.edu.au/research/for-research-students/research-journey/designing-and-undertaking-your-research/reviewing-the-literature http://intranet.ecu.edu.au/student/my-studies/study-advice/academic-tip-sheets

The Abstract

An abstract is a summary of your literature review. It is made up of the following parts:

• A contextual sentence about your motivation behind your research topic
• Your thesis statement
• A descriptive statement about the types of literature used in the review
• Summarize your findings
• Conclusion(s) based upon your findings

The Introduction

Like a typical research paper introduction, provide the reader with a quick idea of the topic of the literature review:

• Define or identify the general topic, issue, or area of concern. This provides the reader with context for reviewing the literature.
• Point out overall trends in what has been published about the topic; or conflicts in theory, methodology, evidence, and conclusions; or gaps in research and scholarship; or a single problem or new perspective of immediate interest.
• Establish the your reason (point of view) for reviewing the literature; explain the criteria to be used in analyzing and comparing literature and the organization of the review (sequence); and, when necessary, state why certain literature is or is not included (scope).

The body of a literature review contains your discussion of sources and can be organized in 3 ways-

• Chronological - by publication or by trend
• Thematic - organized around a topic or issue, rather than the progression of time
• Methodical - the focusing factor usually does not have to do with the content of the material. Instead, it focuses on the "methods" of the literture's researcher or writer that you are reviewing

You may also want to include a section on "questions for further research" and discuss what questions the review has sparked about the topic/field or offer suggestions for future studies/examinations that build on your current findings.

The Conclusion

In the conclusion, you should:

Conclude by providing some insight into the relationship between the central topic of the literature review and a larger area of study such as a discipline, a scientific endeavor, or a profession

The Bibliography

Since a literature review is composed of pieces of research, it is very important that your correctly cite the literature you are reviewing, both in the reviews body as well as in a bibliography/works cited. To learn more about different citation styles, visit the " Citing Your Sources " tab.

• << Previous: Step 5: Synthesizing Content
• Next: Step 7: Citing Your Sources >>
• Last Updated: Apr 1, 2024 9:42 AM
• URL: https://libguides.llu.edu/literaturereview

Conducting a Literature Review

• Getting Started
• Define your Research Question
• Finding Sources
• Evaluating Sources
• Organizing the Review
• Cite and Manage your Sources

Introduction

Once you have your literature review planned out, you are ready to begin writing! Good organization and a clear focus are key to writing a successful academic paper of any kind, which is why the previous steps in this guide are so important; the more thorough you are with each of the preceding elements of writing the literature review, the easier this final step will be.

A literature review is organized into an introduction, multiple body paragraphs, and a conclusion. This format should be familiar to you, as it is the general outline of most academic essays; what is new and exciting about this literature review is the information you've gathered in your research and synthesized in your organization and outlining process.

Remember, if you ever need help with writing an essay of any kind, the ACPHS Writing Center is here to help! You can book an appointment with one of the peer tutors or reach out by email. The Library is also here to provide assistance with your assignments, particularly finding or citing resources.

Additional Resources

• Write a Literature Review by the University of Guelph McLaughlin Library

The ACPHS Writing Center

The Center for Student Success

Writing Center

Laura Rogers, D.A. Director of the Writing Center  Tel: (518) 694-7261 [email protected]

URL:  https://www.acphs.edu/campuses/albany-campus/writing-center

Make an appointment

Intro Paragraph & Thesis

Introductory paragraphs can be the most challenging part of writing a paper. Instead of laying out the evidence (or in the case of a literature review, analyzing your resources), you must first provide background information and context for the topic, discuss the body of literature in general as well as the scope of your review, and give a brief outline of how you will organize the review.

It is generally a good idea to open an introduction with a hook, or an interesting first sentence. This could be a statistic or fact about the topic that you find relevant, a rhetorical question that will be answered in the rest of the introduction, or even an appropriate anecdote. The point of a strong hook is to catch the reader's attention; for a literature review, it can help get the reader invested in the research around your topic, as well as your analysis of it.

Some authors prefer to write their introductory paragraph after completing the body of the essay, finding it easier to summarize what will be shared with the reader after it has already been written. There is no right or wrong order for crafting your paper, so if this method appeals to you then you should make use of it. However, with appropriately detailed planning it can be simple to write out an introduction prior to the body. Using an outline  (using the methods provided by Walden University, for example) can make writing the introduction and the entire essay much simpler.

Your literature review's introduction should contain four major elements:

• Establishing the topic, including providing background information and any necessary definitions to make sure your reader has all the context necessary to understand the rest of the literature review
• The trends or themes of the research that you noticed while compiling your sources, including any that you will use to organize your literature
• The purpose, criteria, and scope of the literature review: how will the literature be organized? What is your reason for examining this topic? What will you be analyzing about the sources (comparing/contrasting research methodology, conclusions, etc.)? Is there any literature you decided not to include -- if so, what disqualified it from the review?
• Introduce your thesis statement by drawing on the previous 3 components of the introduction to state what you discovered about the literature on this topic. Specifically, the thesis should answer where the current literature's strengths and weaknesses lie, and where additional research may be needed

The purpose of the introduction is to make sure that your reader has all the information they need to understand and appreciate your literature review, and to provide them a general blueprint of the analysis and arguments you will be making.

• 5 Questions to Strengthen Your Thesis Statement by the University of Guelph Digital Learning Commons

Body Paragraphs

With the introduction out of the way -- or perhaps even before you've written the introduction -- it's time to examine the literature you've gathered. We established how to organize the literature in the previous section of this guide, and that organization will serve as the framework for the body paragraphs. For example, if you organized your literature into themes, then each theme would serve as its own paragraph, in which you'd compare and contrast the sources within each theme; if you organized it by methodology or historical era, each of those would be a body paragraph.

As you write your literature analyses, keep the following recommendations in mind, provided by Shona McCombes at Scribbr :

Summarize  and synthesize:  give an overview of the main points of each source and combine them into a coherent whole Analyze and interpret:  don’t just  paraphrase  other researchers—add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole Critically evaluate:  mention the strengths and weaknesses of your sources Write in well-structured paragraphs:  use  transition words  and  topic sentences  to draw connections, comparisons and contrasts

Your summary of each source can be as detailed as is appropriate, based on how important the source is to the overall literature or how much analysis you have to perform on it. In general, the more significant a source is to your review, the more time should be devoted to summarizing and analyzing it.

While looking at individual sources, remember to keep connecting them back to the theme of the body paragraph and the overall thesis; explaining their relevance in a particular section of literature helps the reader follow along and better understand your overall arguments.

Other useful tips to keep in mind when writing your body paragraphs, provided by the Writing Center of the University of North Carolina at Chapel Hill :

• Use evidence to support your claims
• Be selective, and focus on the most important points for each piece of literature rather than trying to describe everything
• Use quotes when appropriate, but know that literature reviews do not frequently require direct quotations
• Paraphrase accurately
• Literature Reviews by the University of North Carolina at Chapel Hill's Writing Center

Conclusion & Reviewing Your Paper

Concluding Paragraph

A conclusion is used to provide further reinforcement of the arguments presented throughout the paper. In general, this consists of briefly summarizing the body paragraphs and reasserting their connection to your thesis. This is also good practice for a literature review; in addition, your conclusion should again summarize the broad trends of the research on your topic, as well as any opportunities for additional or more thorough research that you've found. 

Below are some helpful recommendations for writing conclusions, compiled from advice explained in more detail in the links below:

• Address the broader implications of the existing research, and why it is important to close the gaps you evaluated during your literature review
• Include a quotation or fact that effectively illustrates your thesis in a provocative or interesting way
• Use simple, clear language without jargon
• Reestablish your thesis and its connection with the literature reviewed

Your goal with the concluding paragraph of your literature review should be to leave the reader with a firm understanding of the existing literature on your topic, where additional research may be necessary, and why it matters.

Revising Your Literature Review

Revision is a process that goes beyond simply correcting spelling and grammar mistakes -- though proofreading is an important part of the writing process as well. The purpose of revising your literature review before submission is to look at it the way your reader will and pick up on any potential leaps of logic, unclear explanations, or shoddy evidence. The revision process should not begin immediately after finishing the paper; whenever possible, wait a few hours or days before looking at your draft, so that you can approach it with fresh eyes. 

When revising, focus on major issues with the paper such as organization, clarity, and thoroughness. Trying to both revise your writing and proofread it for small spelling or grammar issues may distract you from more important areas that could be improved. Ask yourself if your thesis is well-defended by the body paragraphs, and if you still agree with the conclusions you stated in the introduction. If more or better arguments are needed, find places in the body paragraphs to add evidence or make clearer connections to your thesis. Focus on the flow of the review; does each body paragraph move naturally into the next one? Do your paragraphs need to be reordered or restructured?

After major revisions are done, it is time to proofread for spelling, grammar, and general writing errors. Try reading the paper out loud and seeing where your word choice could be strengthened or a run-on sentence could be amended.

It can sometimes be difficult to revise an essay on your own, so consider booking an appointment with the ACPHS Writing Center to go over your writing with a tutor. Friends, classmates, or your professor can also be useful sources of feedback, and if possible try to get as many different readers to look over your writing and provide insight.

• Revising Drafts by the University of North Carolina at Chapel Hill Writing Center
• << Previous: Organizing the Review
• Next: Cite and Manage your Sources >>
• Last Updated: Apr 12, 2024 10:37 AM
• URL: https://libraryservices.acphs.edu/lit_review

• Library Accounts

Writing a Literature Review

• Getting Started
• Planning a review
• Exploring the Literature
• Managing the Review

Organizing and Writing the Review

Organizing the review, writing the review, online resources.

After selecting the citations for inclusion into the review, it is time to outline and organize the literature review.  There are three basic components of a literature review: Introduction, Body, and Conclusion. Once the details of the outline are complete: it is time to write the literature review chapter of the research paper.   

Introduction to the review.   It should be brief, describing the body of the literature review in terms of format and logical structure. This covers areas such as the research problem, methodology, and the literature that addresses the context of the research study.

Body of the Literature Review . It serves as the logical structure for describing the study’s conceptual or theoretical frameworks. It should cite seminal studies regarding the research problem.  This is where the reviewer can take the liberty of synthesizing what you learned during the course of the literature search. If using subheadings to organize your content in the literature review, then divide by category.

The reviewer may find it useful to format subdivisions of the review. Below are some common subheadings that can divide the review into categories:

• Methodology
• Research findings

Conclusion.   It should also be brief succinctly summarizing what the researcher learned from the review and how it supports the underpinnings of the research study, identifies gaps in the literature and how it justifies the research study.

Writing the Review  You completed all phases in the process. It is time to write the literature review for your research paper. 

Here are a few tips for writing the review

Tip #1:  Know your audience Before writing, identify your audience: who reads the publication where you are submitting your manuscript?

Tip #2:  Avoid jargon Especially if writing for a general audience. Do not use extravagant words.

Tip #3: Keep paragraphs short Pare down excessive wordage when possible. Remember: brevity of content.  Keep review logical structure intact when writing.

Tip #4 : Use subheadings to clarify and lend coherence to review structure Subheadings help organize the review Use subheadings to drill down concepts you cover in the review.

        Tip #5: Focus and preserve continuity Stay on point, keep your focus, and do not stray.

Tip #6: Sustain logical flow Remember, the logical structure of your paper, makes your case in all instances. 

Tip #7: Avoid quotations Use only in rare instances. Always use paraphrasing whenever possible.

Tip #8:   Do not cite references you have not read! If you have not read the article, then DO NOT cite it.

Tip #9:   Use prudence in citing number of studies used Do not cite every source: only sources directly relevant.

Your goal: The reader, upon having read the literature review, should have confidence the author has a thorough understanding of the research topic; the reader has an appreciation of the research problem covered in the study through a grounding of the literature review.  

For further information, check out these Lib-Guides.

University of Pittsburgh. Literature Review

Kent State University. How to do a Literature Review

Boston College. Writing a Literature Review

U.C. Santa Cruz. Write a Literature Review

• << Previous: Managing the Review
• Last Updated: Jul 3, 2023 4:49 PM
• URL: https://guides.library.unlv.edu/LiteratureReview
• Special Collections
• Architecture Library
• Medical Library
• Music Library
• Teacher Library
• Law Library

• Writing Center
• Current Students
• Online Only Students
• Faculty & Staff
• Parents & Family
• Alumni & Friends
• Community & Business
• Student Life
• Video Introduction
• Become a Writing Assistant
• All Writers
• Graduate Students
• ELL Students
• Campus and Community
• Testimonials
• Encouraging Writing Center Use
• Incentives and Requirements
• Open Educational Resources
• How We Help
• Get to Know Us
• Conversation Partners Program
• Workshop Series
• Professors Talk Writing
• Computer Lab
• Starting a Writing Center
• A Note to Instructors
• Annotated Bibliography
• Literature Review
• Research Proposal
• Argument Essay
• Rhetorical Analysis

Literature Review Assignment

Note to instructors: This literature review assignment may be used as part of an ongoing research project, or it may be used as a stand-alone project. You are encouraged to adopt, adapt, or remix these guidelines to suit your goals for your class.

Rough Draft:

Peer Review:

Final Draft:

This assignment will help you become aware of how writers and researchers consider previous work on a topic before they begin additional research. 

• Locate a variety of scholarly print and digital sources that represent multiple perspectives on a topic.
• Analyze sources by critically reading, annotating, engaging, comparing, and drawing implications.
• Methods of gathering and determining the credibility of sources
• Strategies for identifying and discussing multiple perspectives in research

A literature review provides context and establishes the need for new research. In your literature review, you will summarize and analyze published research on your topic by identifying strengths, weaknesses, commonalities, and disagreements among your sources.

For this assignment, you will conduct research on your topic and then compose a thoughtful, well-organized literature review that reflects your own analysis of at least five scholarly sources and their contributions to your topic. (Note that a literature review differs from an annotated bibliography, which simply lists sources and summaries one-by-one. A literature review also differs from a research paper because it does not include new arguments or unpublished primary research.)

Your literature review should have three parts: an introduction, a body, and a conclusion.

Introduction

In the introduction, identify your research topic and provide appropriate background information to clarify the context in which you will be reviewing the sources. You should also identify commonalities, conflicts, and/or gaps in published research. Finally, you should explain the criteria you’ve used to analyze, compare, and contrast sources.

In the body, discuss your sources. Organize your discussion of sources based on a common characteristic such as authors’ purposes, findings, or conclusions; research methodologies; or chronology. Briefly summarize each source and describe the strengths and weaknesses of each source. Identify and analyze each source’s contribution to the topic and address differing viewpoints. Integrate source information effectively using lead-in phrases and citations. 

In the conclusion, discuss the ways your sources have contributed to greater knowledge and understanding of the topic and address shortcomings in the existing research. Answer the following questions: What has your review of the sources revealed or demonstrated about the topic? What new questions that have been raised? What areas need further study? 

Formatting requirements

Follow MLA format. Use black Calibri or Times New Roman font in size 12. Double-space the entire document. Use 1-inch margins on all sides.

Criteria for success

General criteria:.

• The writing is clear and coherent/makes sense. 
• The tone and language are appropriate for the audience.
• The writing adheres to grammar and punctuation rules.
• All sources are cited properly, both within the literature review and on the Works Cited page. 

In the introduction, you should . . .

• Identify the general topic or issue you have researched.
• Provide appropriate background information to clarify the context in which you will be reviewing sources. 
• Identify overall trends conflicts, and/or gaps in research and scholarship; and/or identify a single problem or new perspective. 
• Explain the criteria you’ve used to analyze, compare, and contrast sources.
• When necessary, state why certain sources are, or are not, included. 

In the body, you should . . .

• Include at least five scholarly sources.
• Organize discussion of sources logically according to a common characteristic (E.g.: authors’ purposes, findings, or conclusions; research methodologies; or chronology)
• Briefly summarize individual sources.
• Describe strengths of each source.
• Describe weaknesses of each source.
• Identify and analyze each source’s contribution to the topic. 
• Address differing viewpoints.
• Integrate source information effectively using lead-in phrases and citations.

In the conclusion, you should . . .

• Discuss the ways your sources have contributed to greater knowledge and understanding of the topic.
• Address shortcomings in the existing research. 
• Note new information or understanding the literature review has revealed about the topic. 
• Note new questions that have been raised.
• Note areas where further study is needed.

The literature review should adhere to all formatting criteria:

• Follow MLA format throughout the literature review and on the Works Cited page.
• The entire document should be double-spaced. 
• The font should be Calibri or Times New Roman in size 12.
• The margins should be one inch on all sides.

This material was developed by the COMPSS team and is licensed under a  Creative Commons Attribution 4.0 International License . All materials created by the COMPSS team are free to use and can be adopted, adapted, and/or shared as long as the materials are attributed. Please keep this information on materials you adopt, adapt, and/or share. 

Contact Info

Kennesaw Campus 1000 Chastain Road Kennesaw, GA 30144

Marietta Campus 1100 South Marietta Pkwy Marietta, GA 30060

Campus Maps

Phone 470-KSU-INFO (470-578-4636)

kennesaw.edu/info

Media Resources

Resources For

Related Links

• Financial Aid
• Degrees, Majors & Programs
• Job Opportunities
• Campus Security
• Global Education
• Sustainability
• Accessibility

470-KSU-INFO (470-578-4636)

© 2024 Kennesaw State University. All Rights Reserved.

• Privacy Statement
• Accreditation
• Emergency Information
• Reporting Hotline
• Open Records
• Human Trafficking Notice

The Literature Review: 5. Organizing the Literature Review

• 1. Introduction
• 2. Why Do a Literature Review?
• 3. Methods for Searching the Literature
• 4. Analysing the Literature
• 5. Organizing the Literature Review
• 6. Writing the Review

1. Organizing Principles

A literature review is a piece of discursive prose, not a list describing or summarizing one piece of literature after another. It should have a single organizing principle:

• Thematic - organize around a topic or issue
• Chronological - sections for each vital time period
• Methodological - focus on the methods used by the researchers/writers

4. Selected Online Resources

• Literature Review in Education & Behavioral Sciences This is an interactive tutorial from Adelphi University Libraries on how to conduct a literature review in education and the behavioural sciences using library databases
• Writing Literature Reviews This tutorial is from the Writing section of Monash University's Language and Learning Online site
• The Literature Review: A Few Tips on Conducting It This guide is from the Health Services Writing Centre at the University of Toronto
• Learn How to Write a Review of the Literature This guide is part of the Writer's Handbook provided by the Writing Center at the University of Wisconsin-Madison

2. Structure of the Literature Review

Although your literature review will rely heavily on the sources you read for its information, you should dictate the structure of the review. It is important that the concepts are presented in an order that makes sense of the context of your research project.

There may be clear divisions on the sets of ideas you want to discuss, in which case your structure may be fairly clear. This is an ideal situation. In most cases, there will be several different possible structures for your review.

Similarly to the structure of the research report itself, the literature review consists of:

• Introduction

Introduction - profile of the study

• Define or identify the general topic to provide the context for reviewing the literature
• Outline why the topic is important
• Identify overall trends in what has been published about the topic
• Identify conflicts in theory, methodology, evidence, and conclusions
• Identify gaps in research and scholarlship
• Explain the criteria to be used in analysing and comparing the literature
• Describe the organization of the review (the sequence)
• If necessary, state why certain literature is or is not included (scope)

Body - summative, comparative, and evaluative discussion of literature reviewed

For a thematic review:

• organize the review into paragraphs that present themes and identify trends relevant to your topic
• each paragraph should deal with a different theme - you need to synthesize several of your readings into each paragraph in such a way that there is a clear connection between the sources
• don't try to list all the materials you have identified in your literature search

From each of the section summaries:

• summarize the main agreements and disagreements in the literature
• summarize the general conclusions that have been drawn
• establish where your own research fits in the context of the existing literature

5. A Final Checklist

• Have you indicated the purpose of the review?
• Have you emphasized recent developments?
• Is there a logic to the way you organized the material?
• Does the amount of detail included on an issue relate to its importance?
• Have you been sufficiently critical of design and methodological issues?
• Have you indicated when results were conflicting or inconclusive and discussed possible reasons?
• Has your summary of the current literature contributed to the reader's understanding of the problems?

3. Tips on Structure

A common error in literature reviews is for writers to present material from one author, followed by information from another, then another.... The way in which you group authors and link ideas will help avoid this problem. To group authors who draw similar conclusions, you can use linking words such as:

• additionally

When authors disagree, linking words that indicate contrast will show how you have analysed their work. Words such as:

• on the other hand
• nonetheless

will indicate to your reader how you have analysed the material. At other times, you may want to qualify an author's work (using such words as specifically, usually, or generally ) or use an example ( thus, namely, to illustrate ). In this way you ensure that you are synthesizing the material, not just describing the work already carried out in your field.

Another major problem is that literature reviews are often written as if they stand alone, without links to the rest of the paper. There needs to be a clear relationship between the literature review and the methodology to follow.

• << Previous: 4. Analysing the Literature
• Next: 6. Writing the Review >>
• Last Updated: Feb 8, 2022 5:25 PM
• URL: https://libguides.uwi.edu/litreviewsoe

Ask a Librarian

• Clarify Your Topic
• Research Your Topic
• Write Your Review
• Citing Your Sources
• Other Guides and Resources
• University of Washington Libraries
• Library Guides
• Literature Reviews

Literature Reviews: Write Your Review

Critical analysis.

A critical analysis of your sources is key to creating a quality literature review, and keeping your research question in mind as you read the literature will ensure that you are on track.

• As you read, ask yourself "Why is my topic important?" You must evaluate and interpret the information to discover your own point of view.

Reading and Evaluating Scholarly Literature (Oregon State University)

Evaluating Resources (University of Southern California)

Critically Analyzing Information Sources (Cornell University Library)

Literature Review Model

• What Constitutes a Good Literature Review and Why Does its Quality Matter? A discussion of the state of literature reviews found in scholarly journals. The author discusses the need for clear identification of the "problem domain" or scope of a topic, and the critical need for "identifying and articulating knowledge gaps" in literature reviews. more... less... Maier, H. R. (May 01, 2013). What constitutes a good literature review and why does its quality matter?. Environmental Modelling & Software, 43, 3-4.

Once you identify your topic, check for existing literature reviews in your area of interest that can be used as models.

• Search UW Libraries Catalog using your search terms in conjunction with "literature review" or "methods" or "research" or "bibliography".

What Does a Literature Review Look Like?

This sample literature review from the Purdue University Online Writing Lab (OWL), provides an example in the field of psychology.

Structure of a Literature Review

A literature review has a format similar to other scholarly papers. It contains an introduction, body and conclusion, but is focused exclusively on the research of others.

The Basics of a Literature Review. (2014). Teaching and Learning Center University of Washington Tacoma. Retrieved from  https://www.tacoma.uw.edu/sites/default/files/2021-05/basics-of-lit-review1.pdf 

Guidelines for Writing Your Literature Review

The creation of a literature review involves reading articles , processing the information from the articles, and integrating that information in the larger context of the review

The Basics of a Literature Review. (2014). Teaching and Learning Center University of Washington Tacoma. Retrieved from  https://www.tacoma.uw.edu/sites/default/files/2021-05/basics-of-lit-review1.pdf

Types of Source Materials

Primary Resources - These resources are the basic building blocks for the other types of resources. They include empirical research , firsthand accounts of events and other original materials .

Secondary Resources - These are resources that analyze or interpret primary and other secondary resources .

Tertiary Resources - These include encyclopedias, textbooks, dictionaries, handbooks, and indexes. They provide a summary and definitions of topics and are an effective and efficient way to begin to build your project.

• << Previous: Research Your Topic
• Next: Citing Your Sources >>
• Last Updated: Mar 2, 2023 3:02 PM
• URL: https://guides.lib.uw.edu/tacoma/literaturereview

• Writing well

How to write a literature review

• Starting well
• How to write an annotated bibliography
• How to write a case study response
• How to write a critique
• How to write an empirical article
• How to write an essay
• How to write a reflective task
• How to write a report
• Finishing well

Structure of a literature review

Determine your purpose.

Work out what you need to address in the literature review. What are you being asked to do in your literature review? What are you searching the literature to discover? Check your assignment question and your criteria sheet to know what to focus on.

Do an extensive search of the literature

Find out what has been written on the topic.

What kind of literature?

Select appropriate source material: Use a variety of academic or scholarly sources that are relevant, current and authoritative. An extensive review of relevant material will include — books, journal articles, reports, government documents, conference proceedings and web resources. The Library would be the best place to search for your sources.

How many resources?

The number of sources that you will be required to review will depend on what the literature review is for and how advanced you are in your studies. It could be from five sources at first year undergraduate level to more than fifty for a thesis. Your lecturer will advise you on these details.

Note the bibliographical details of your sources

Keep a note of the publication title, date, authors’ names, page numbers and publishers. These details will save you time later.

Read the literature

• Critically read each source, look for the arguments presented rather than for facts.
• Take notes as you read and start to organise your review around themes and ideas.
• Consider using a table, matrix or concept map to identify how the different sources relate to each other.

Analyse the literature you have found

In order for your writing to reflect strong critical analysis, you need to evaluate the sources. For each source you are reviewing ask yourself these questions:

• What are the key terms and concepts?
• How relevant is this article to my specific topic?
• What are the major relationships, trends and patterns?
• How has the author structured the arguments?
• How authoritative and credible is this source?
• What are the differences and similarities between the sources?
• Are there any gaps in the literature that require further study?

Write the review

• Start by writing your thesis statement. This is an important introductory sentence that will tell your reader what the topic is and the overall perspective or argument you will be presenting.
• Like essays, a literature review must have an introduction, a body and a conclusion.

Introduction

Your introduction should give an outline of:

• why you are writing a review, and why the topic is important
• the scope of the review — what aspects of the topic will be discussed
• the criteria used for your literature selection (e.g. type of sources used, date range)
• the organisational pattern of the review.

Body paragraphs

Each body paragraph should deal with a different theme that is relevant to your topic. You will need to synthesise several of your reviewed readings into each paragraph, so that there is a clear connection between the various sources. You will need to critically analyse each source for how they contribute to the themes you are researching.

The body could include paragraphs on:

• historical background
• methodologies
• previous studies on the topic
• mainstream versus alternative viewpoints
• principal questions being asked
• general conclusions that are being drawn.

Your conclusion should give a summary of:

• the main agreements and disagreements in the literature
• any gaps or areas for further research
• your overall perspective on the topic.
• outlined the purpose and scope?
• identified appropriate and credible (academic/scholarly) literature?
• recorded the bibliographical details of the sources?
• analysed and critiqued your readings?
• identified gaps in the literature and research?
• explored methodologies / theories / hypotheses / models?
• discussed the varying viewpoints?
• written an introduction, body and conclusion?
• checked punctuation and spelling?

Further information

• HiQ: Managing weekly readings
• HiQ: Notetaking
• HiQ: Structuring your assignment
• RMIT University: Literature review - Overview

Global links and information

• Referencing and using sources
• Background and development
• Changes to QUT cite|write
• Need more help?
• Current students
• Current staff
• TEQSA Provider ID: PRV12079 (Australian University)
• CRICOS No. 00213J
• ABN 83 791 724 622
• Last modified: 07-Mar-2023
• Accessibility
• Right to Information
• Feedback and suggestions

Acknowledgement of Traditional Owners

QUT acknowledges the Traditional Owners of the lands where QUT now stands.

How do I Write a Literature Review?: #5 Writing the Review

• Step #1: Choosing a Topic
• Step #2: Finding Information
• Step #3: Evaluating Content
• Step #4: Synthesizing Content
• #5 Writing the Review
• Citing Your Sources

WRITING THE REVIEW 

You've done the research and now you're ready to put your findings down on paper. When preparing to write your review, first consider how will you organize your review.

The actual review generally has 5 components:

Abstract  -  An abstract is a summary of your literature review. It is made up of the following parts:

• A contextual sentence about your motivation behind your research topic
• Your thesis statement
• A descriptive statement about the types of literature used in the review
• Summarize your findings
• Conclusion(s) based upon your findings

Introduction :   Like a typical research paper introduction, provide the reader with a quick idea of the topic of the literature review:

• Define or identify the general topic, issue, or area of concern. This provides the reader with context for reviewing the literature.
• Identify related trends in what has already been published about the topic; or conflicts in theory, methodology, evidence, and conclusions; or gaps in research and scholarship; or a single problem or new perspective of immediate interest.
• Establish your reason (point of view) for reviewing the literature; explain the criteria to be used in analyzing and comparing literature and the organization of the review (sequence); and, when necessary, state why certain literature is or is not included (scope)  - 

Body :  The body of a literature review contains your discussion of sources and can be organized in 3 ways-

• Chronological -  by publication or by trend
• Thematic -  organized around a topic or issue, rather than the progression of time
• Methodical -  the focusing factor usually does not have to do with the content of the material. Instead, it focuses on the "methods" of the literature's researcher or writer that you are reviewing

You may also want to include a section on "questions for further research" and discuss what questions the review has sparked about the topic/field or offer suggestions for future studies/examinations that build on your current findings.

Conclusion :  In the conclusion, you should:

Conclude your paper by providing your reader with some perspective on the relationship between your literature review's specific topic and how it's related to it's parent discipline, scientific endeavor, or profession.

Bibliography :   Since a literature review is composed of pieces of research, it is very important that your correctly cite the literature you are reviewing, both in the reviews body as well as in a bibliography/works cited. To learn more about different citation styles, visit the " Citing Your Sources " tab.

• Writing a Literature Review: Wesleyan University
• Literature Review: Edith Cowan University
• << Previous: Step #4: Synthesizing Content
• Next: Citing Your Sources >>
• Last Updated: Aug 22, 2023 1:35 PM
• URL: https://libguides.eastern.edu/literature_reviews

About the Library

• Collection Development
• Circulation Policies
• Mission Statement
• Staff Directory

Using the Library

• A to Z Journal List
• Library Catalog
• Research Guides

Interlibrary Services

• Research Help

Warner Memorial Library

Library & Information Services

Literature reviews: parts & organization of a literature review.

• Back to Lovejoy Library
• Literature Reviews

Parts & Organization of a Literature Review

• Why are Literature Reviews Important

Literature reviews typically follow the introduction-body-conclusion format. If your literature review is part of a larger project or paper, the introduction and conclusion of the lit review may be just a few sentences, while you focus most of your attention on the body. If it is a standalone piece, then the introduction and conclusion may take up more space.

A literature review typically follows this model:

Introduction:

• An introductory paragraph that explains what your working topic and thesis is.
• Noting key topics or texts that will appear in the review.
• A potential description of how you found your sources, and how you chose them for inclusion and discussion for your review.
• Summarize and synthesize : Give an overview of the main points of each source and combine them into a coherent whole.
• Analyze and interpret : Don’t just paraphrase other researchers and their voices – add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole.
• Critically Evaluate : Mention strengths and weaknesses of your sources.
• Write in well-structured paragraphs : Use this body paragraph space to draw and show connections, comparisons, and contrasts between your selected sources.

Conclusion:

• Summarize the key findings you have taken from the literature and emphasize their significance.
• Connect it back to your primary research question. Remind readers what your thesis is.

Purdue University – Purdue Online Writing Lab. (n.d.). What are the Parts of a Lit Review?; How Should I Organize My Lit Review?. Retrieved from: https://owl.purdue.edu/owl/research_and_citation/conducting_research/writing_a_literature_review.html

• << Previous: Why are Literature Reviews Important
• Next: Example >>
• Last Updated: Sep 9, 2021 3:29 PM
• URL: https://libguides.siue.edu/litreview

ON YOUR 1ST ORDER

How to Conclude a Literature Review

By Laura Brown on 6th March 2019

The conclusion of the dissertation literature review focuses on a few critical points,

• Highlight the essential parts of the existing body of literature in a concise way.
• Next, you should analyse the current state of the reviewed literature .
• Explain the research gap for your chosen topic/existing knowledge.
• Now, outline the areas for future study by mentioning main agreements and disagreements in the literature.
• Finally, link the research to existing knowledge .

Now, any of you who have been into research would agree that literature review is a very exhausting process and may stress you during your academic career. It is tougher because it requires you to be organised. We have seen many students asking does a literature review need a conclusion.

Well, the answer is simple, a good literature review will always have a proper ending. But there is nothing to worry about how to write a conclusion for a literature review. Here is a complete guide for you in “four” simple yet convenient steps. These steps can really be valuable in providing an excellent presentation to your literature review help . Furthermore, you can ask us for literature review conclusion examples anytime using our live chat or email option.

Now, without further ado, let’s move towards the steps.

How To Write A Literature Review Conclusion

Get Expert Assistance For Literature Review

Here are four major steps which can help you with how to conclude a literature review with ease.

1. Enlist Key Points

The conclusion can also be said as judgement because it gives a clear view of your work, whether you achieved your targeted objectives or not. Typically, it is not too difficult to conclude a review, but it can be challenging as well if not carried out properly.

It is crucial to find key features which should be engaging and useful as well for a reader. So at first, draft or enlist key factors before moving forward towards initialising your summary.

2. Summarise The Key Features Briefly

This is a most sensitive and important step of a dissertation literature review conclusion, where you should stick to the following things to get the job done efficiently.

• Once you are done drafting the important points , here you should mention them briefly.
• You can also take the liberty to agree or disagree with whatever literature you have gone through.
• Make sure you don’t drag your arguments while counter-arguing. Keeping your points specific is key.
• Describe, in one to two lines, how you addressed the previously identified gap .
• It is also important to point out the lapses you have noticed in previous authors’ work. Those lapses could be a misquotation of figures, a wrong pattern of research and so on.
• Alongside this, discuss existing theories and methods to build a framework for your research.

3. Educational Implications Of The Reviewed Literature

After mentioning the key factors, it is suggested to put implications to the already reviewed research. Like, as identifying problems in the already done research and giving recommendations on how these problems can be resolved.

Need Help in Writing Your Literature Review?

4. Indicating Room For Future Research

After completing the whole analysis of the particular research, you will be capable of identifying the work which can be done in future. You can also leave some gaps for future researchers so others can extend your work. This will be the final step, and this is how to end a literature review.

Tips That Can Enlighten Your Conclusion

We hope that things are very clear to you on how to write a conclusion for a literature review. If you want it to be even better and more meaningful, then you should keep the below points in mind.

• It should not be burdened with an unnecessary chain of details.
• It should be as precise and easy to understand as possible.
• You should mention important key points and findings .
• Make sure to put all points in a flow so the reader can understand your research in one go.
• Do not add anything from your own.

“Simply put, touch the prominent factors and leave them unexplained here”.

Get Help to Conclude Your Literature Review

If you are able to keep your focus around these steps and mentioned points, believe us, you will never ask anyone how to conclude literature review.

Looking At Literature Review Conclusion Example

Below are three examples which will help you understand how to conclude a literature review.

1. Firstly, you should summarise the important aspects and evaluate the current state of the existing literature.

Overall, the findings from this literature review highlight the need for further research to address the gaps in knowledge on the effectiveness of mindfulness-based interventions for reducing symptoms of anxiety and depression in college students.

2. Now, along with mentioning the gaps, come up with your approach to future study.

Therefore, to address this gap in the literature, we incorporated larger and more diverse samples, used standardised measures of mindfulness and mental health outcomes, and included longer follow-up periods to assess the long-term effects of mindfulness-based interventions on anxiety and depression.

3. Now summarise on how your findings will contribute to the particular field by linking it to the existing knowledge.

The findings from the study will provide important insights for researchers, clinicians, and educators interested in developing and implementing effective interventions to promote mental health and well-being among college students, and highlight the need for further research to establish the effectiveness of mindfulness-based interventions in this population.

We hope that these examples will bring in more clarification and you can have a better idea about the literature review conclusion.

What basically is a literature review?

What are the 3 primary parts of a literature review, what are the goals of writing a literature review.

There are four primary objectives of writing a literature review:

1. Determining the background from the previous scholarly literature related to the topic.

2. Identifying the gaps between literature to boost further research.

3. Analysing if the theory is applicable and associating a suitable methodology.

Why is a literature review conclusion necessary?

• https://azhin.org/cummings/basiclitreview/conclusions
• https://www.citewrite.qut.edu.au/write/writing-well/litreview.html
• https://psychology.ucsd.edu/undergraduate-program/undergraduate-resources/academic-writing-resources/writing-research-papers/writing-lit-review.html
• https://students.unimelb.edu.au/academic-skills/resources/report-writing/reviewing-the-literature

Laura Brown, a senior content writer who writes actionable blogs at Crowd Writer.

• Open access
• Published: 12 April 2024

Performance and application of the total-body PET/CT scanner: a literature review

• Yuanyuan Sun 1 ,
• Zhaoping Cheng 2 ,
• Jianfeng Qiu 1 &
• Weizhao Lu   ORCID: orcid.org/0000-0002-2941-9791 3  

EJNMMI Research volume  14 , Article number:  38 ( 2024 ) Cite this article

70 Accesses

Metrics details

The total-body positron emission tomography/computed tomography (PET/CT) system, with a long axial field of view, represents the state-of-the-art PET imaging technique. Recently, the total-body PET/CT system has been commercially available. The total-body PET/CT system enables high-resolution whole-body imaging, even under extreme conditions such as ultra-low dose, extremely fast imaging speed, delayed imaging more than 10 h after tracer injection, and total-body dynamic scan. The total-body PET/CT system provides a real-time picture of the tracers of all organs across the body, which not only helps to explain normal human physiological process, but also facilitates the comprehensive assessment of systemic diseases. In addition, the total-body PET/CT system may play critical roles in other medical fields, including cancer imaging, drug development and immunology.

Therefore, it is of significance to summarize the existing studies of the total-body PET/CT systems and point out its future direction. This review collected research literatures from the PubMed database since the advent of commercially available total-body PET/CT systems to the present, and was divided into the following sections: Firstly, a brief introduction to the total-body PET/CT system was presented, followed by a summary of the literature on the performance evaluation of the total-body PET/CT. Then, the research and clinical applications of the total-body PET/CT were discussed. Fourthly, deep learning studies based on total-body PET imaging was reviewed. At last, the shortcomings of existing research and future directions for the total-body PET/CT were discussed.

Due to its technical advantages, the total-body PET/CT system is bound to play a greater role in clinical practice in the future.

Positron emission tomography (PET) is a molecular imaging technique, and an important diagnostic imaging approach in nuclear medicine [ 1 , 2 , 3 , 4 ]. PET can detect changes in the physiological activity of lesions before morphological alterations occur using different tracers [ 3 ]. Combined with structural imaging modalities such as magnetic resonance imaging (MRI) or computed tomography (CT), PET has played critical roles in the assessment of tumors, neurological disorders and cardiovascular diseases [ 5 , 6 , 7 ].

Since the introduction of the first commercial PET in 1976, PET systems have developed rapidly [ 1 ]. The core of the PET development is essentially the development of detectors [ 8 ]. A dense and fast-decaying scintillator, a highly sensitive photo-sensor, as well as precise custom-designed readout electronics are the three key components of the detector blocks [ 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. The developments of these technologies have transformed PET from the clinical need to capture a single organ to the need to link multiple organs in vivo [ 1 ]. However, limited by the axial field of view (aFOV) of traditional PET scanners, multi-bed positions are necessary to cover the patient’s whole torso (imaging “from eyes to thighs”) during image acquisition [ 8 ], which may result in quantification inaccuracies due to differences in the acquisition time and noise levels [ 15 ]. Henceforth, reducing the number of imaging bed positions and even achieving whole-body imaging has been the trend of PET development [ 1 ]. More importantly, the concept of whole-body imaging has large potential with regard to low-dose imaging, faster scanning, whole-body dynamic imaging and follow-up of tracers over longer periods, which may change the current clinical routine and expand the number of clinical applications of molecular imaging [ 7 ]. The pursuit of total-body imaging advances the aFOV of the detector. PET system reached aFOVs of more than 20 cm in the second half of the 2000s [ 16 , 17 ]. In the late 2010s, the aFOV of the new generation PET scanner has developed to above 1 m [ 16 , 17 ]. These scanners allow total-body acquisition within less than 60 s and thereby will give a real-time insight into (patho-)physiological processes [ 8 ].

Currently, long aFOV (> 50 cm) PET scanners are commercially available worldwide [ 18 ], and three human total-body PET/CT systems have been developed: the PennPET Explorer, the uEXPLORER, and the Biograph Vision Quadra [ 8 ]. These three PET systems all realize aFOVs above 1 m and show a tremendous increase in system sensitivity due to the longer gantries [ 8 ]. The PennPET Explorer, with recently-extended aFOV of 1.12 m and a time-of-flight (TOF) resolution of 250 ps, enables imaging the entire human body with a limited number of bed positions (2–3 bed positions) [ 18 ]. The Biograph Vision Quadra has an aFOV of 106 cm, offering anatomical coverage roughly from head to thighs [ 19 ]. Among the three total-body PET systems, the uEXPLORER is the first real-sense total-body PET/CT with a total aFOV of 194.0 cm and offers uniform sensitivity throughout its one-meter length center [ 20 ].

Compared with traditional PET systems, the long aFOV makes the total-body PET/CT systems possible to simultaneously image most organs of interest in adults with a limited number of bed positions and uniform image quality [ 18 , 19 , 20 , 21 , 22 ]. The total-body PET/CT system enables superb spatial resolution, increased signal-to-noise ratio (SNR), and lesion detection capability, as well as low-dose and sub-second imaging [ 22 , 23 , 24 , 25 , 26 , 27 ]. As the total-body PET/CT has been increasingly used in research and clinical investigations, it is necessary to summarize its performance and clinical applications, with the aim to provide a reference for researchers and to point out its future directions. This review collects studies on total-body PET/CT from the PubMed database over the last 5 years using keywords including total-body PET, whole-body PET, PennPET Explorer, uEXPLORER, or Biograph Vision Quadra and collected 86 publications. The review is divided into the following sections: In “ Main text ” section, we gave a brief introduction of the total-body PET/CT system, reviewed the studies on performance evaluation of the total-body PET/CT, summarized the research and clinical applications of the total-body PET/CT, and summed up deep learning-based studies using the total-body PET/CT. In “ Discussions and conclusions ” section, we presented an outlook on the clinical applications of the total-body PET system based on the summary of the existing literatures.

A brief introduction to the total-body PET/CT system

Compared to conventional PET, the total-body PET/CT system brings the state-of-the-art hardware enhancement, transforming the traditional 20–25 min step-and-shoot scan mode to single-shot whole-body scan (Fig.  1 ). The PennPET Explorer is composed of 6 ring segments, each ring covers a 22.9 cm-long aFOV with 16.4 cm of active detectors. The PennPET Explorer utilizes a detector tile of 64 lutetium-yttrium oxyorthosilicate (LYSO) scintillation crystals [ 18 ]. For the Biograph Vision Quadra, the total axial span of 320 LYSO crystals is directly coupled to a silicon photomultiplier array with 16 output channels. Eight mini blocks form a detector block, with 2 adjacent detector blocks sharing a common electronic unit. This arrangement enables the Biograph Vision Quadra an aFOV of 106 cm [ 28 ]. The uEXPLORER is composed of 8 PET units along the axial direction; each unit is 24.02 cm in axial length, 78.6 cm in diameter, with a 0.26 cm gap between units, making up the system with axial length of 194 cm. There are 24 detector modules in each PET unit, and each module contains 70 block detectors arranged in a 5 × 14 matrix [ 22 ].

Total-body PET/CT versus conventional PET/CT

Performance evaluation of the total-body system

Theoretically, sensitivity gain provided by the long aFOV PET scanner will lead to significant improvements in system performance, which will benefit to low-dose imaging, delayed imaging, ultrafast imaging, and total-body dynamic imaging [ 29 , 30 ]. This section gives a detailed overview of the basic performance evaluation and performance under various extreme conditions for different total-body PET/CT systems.

Basic performance of the total-body system

Studies have evaluated comprehensive performances of the three total-body PET/CT systems using metrics including sensitivity, count-rate performance, time-of-flight resolution, spatial resolution, and image quality based on the NEMA NU-2-2018 protocol [ 22 , 28 , 31 ], and the results are presented in Table  1 . In summary, the three total-body PET/CT systems have good performances in terms of spatial resolution, time resolution and sensitivity. The uEXPLORER scanner provides a very high sensitivity, and the longest aFOV among the three systems [ 32 ]. However, the PennPET Explorer and Quadra have higher time resolution and peak noise equivalent count-rate (P-NECR) [ 25 , 28 ].

Ultrafast imaging

Owing to the increased sensitivity of long aFOV, the total-body PET scanners can generate diagnostic level images with reduced scan time. Researchers simulated the effects of decreased scan time using list-mode data and the results demonstrated that the PennPET Explorer and Quadra can generate images of satisfactory quality in 2 min with comparable SNR and lesion detectability to routine clinical images [ 18 , 19 , 26 , 33 ], while the uEXPLORER can generate images with acceptable image quality in 30 s with SNR and lesion detectability similar to routine clinical images [ 34 ]. In addition, the Quadra and PennPET Explorer PET/CT systems could deliver images of comparable quality and lesion quantification in under 2 min, compared to routine clinical scan of 16 min from short aFOV PET/CT scanner [ 26 ]. Previous studies demonstrated that a protocol with 30–45-s scanning duration and 2 or 3 iterations for the uEXPLORER was found to provide an equivalent image quality as the traditional imaging protocol for the uMI 780 (a clinical 3.0 T MRI scanner from the United Imaging), while the former protocol showed higher SNR for the lesions (Fig.  2 a) [ 35 ], and 60-s images by the uEXPLORER were still feasible in oncological applications, as all the lesions could be identified in 60-s images [ 36 ].

Performance evaluation of the total-body PET systems. a PET transverse and maximum intensity projection (MIP) images of a 64-year-old woman diagnosed with hepatocellular carcinoma. Left panels are reconstructed images with the clinical protocol via a conventional PET/CT scanner (uMI 780), and right panel is reconstructed images with 2 iterations and a 45-s acquisition via the uEXPLORER. The protocol with a 45-s scanning duration and 2 iterations using the uEXPLORER can provide equivalent image quality as the uMI 780 [ 35 ]. b MIP of the full-dose image and axial view of the serial dose reduction images generated by reduced count. Left: An FDG-avid micro-lesion in the liver of a 7-year-old patient with neuroblastoma, with an SUV max of 4.35 on the full-dose image. The lesion is identifiable as reduced down to 1/20-dose and is un-diagnosable at 1/30-dose. Right: A micro-lesion in the subcapsular region of the liver in a 3-year-old patient with Burkitt Lymphoma is diagnosable in all dose reduction images [ 41 ]. c Dynamic scan is acquired after the injection of 496 MBq of 18 F-FDG on a 60-year-old patient with metastatic colon cancer. Panels are 10-min reconstructions at 2.75- and 4.2-h post-injection using the PennPET scanner, respectively [ 33 ]. d Comparison of standard SUV image with parametric images of FDG influx rate K i , fractional blood volume V b , FDG delivery rate K 1 and volume of distribution V 0 images of a cancer patient. The images are shown as MIP maps [ 54 ]. It is worth mentioning that due to the different window widths, tumors may be more apparent in the parametric map than in the SUV map. In fact, there is no difference in tumor numbers between the two set of images

Low-dose imaging

The increased sensitivity of the total-body PET allows reduced dose of the injected radiopharmaceuticals while maintaining acceptable image quality. For Quadra PET/CT system, low-dose (2.0 MBq/kg) 18 F-FDG with reduced scan time up to 5 min provided comparable data to standard acquisition in melanoma diagnose [ 37 ]. A phantom and lesion embedding study with 18 F-fluorothymidine on the PennPET Explorer has shown the ability to accurately estimate kinetic parameters, with doses as low as 0.5–2 mCi [ 38 ].

PET images from the uEXPLORER with 1/20 of the standard injection dose (18.5 MBq/0.5 mCi) are still considered to be of high quality for clinical use [ 34 ]. According to the study by Tan et al., image quality scores, liver SNR, and lesion detectability of PET images with 2-min acquisition time and half-dose (1.85 MBq/kg) by the uEXPLORER were significantly higher than those with full dose by conventional PET scanner [ 39 ]. Later, Tan et al. also investigated lesion detectability in colorectal cancer patients at ultra-low dose (0.37 MBq/kg 18 F-FDG). The study proved that PET images with ultra-low dose and the acquisition time of 1-min was sufficient for clinical diagnosis and lesion detectability, although the image quality was degraded [ 40 ]. Zhao et al. simulated low-dose (1/30–1/2 dose, 0.12–1.85 MBq/kg) images by truncating the list-mode PET data to reducing count density and compared them with full-dose images (3.70 MBq/kg). Results showed that sufficient subjective image quality and lesion conspicuity could be maintained down to 1/30-dose (0.12 MBq/kg) of the administered dose of 18 F-FDG, where good image quality scores were given between 1/2- and 1/10-dose (0.375–1.85 MBq/kg) groups (Fig.  2 b) [ 41 ].

Delayed imaging

In addition to imaging with less injected dose, the high sensitivity of the total-body PET/CT system enables imaging at delayed time points [ 34 ]. Delayed imaging 24 h after injection of 18 F-FDG (half-life 110 min) in humans has been proved to be feasible on the PennPET Explorer [ 33 ], and even more delayed imaging can be obtained for longer-lived radiotracers, such as 89 Zr (half-life 3.3 days), to study slower biologic processes [ 18 ]. As for the uEXPLORER, depending on radiotracer kinetics, delayed imaging may improve contrast in diseased tissues such as atherosclerosis and cancers (Fig.  2 c) [ 42 , 43 ]. Hu et al. tested delayed imaging for different organs in 10 healthy volunteers with 18 F-FDG. In vivo time-activity curves (TACs) of all investigated organs acquired using standard imaging method (up to 75-min post-injection) and delayed imaging method (up to 8-h post-injection) were compared. It was found that the average residence time differences of the brain, heart, kidney, liver, and lungs were 8.38%, 15.13%, 25.02%, 23.94%, and 16.50% between standard imaging delayed imaging methods. In addition, the bladder revealed the largest difference (21.18%) in the effective dose between the two imaging methods among all the investigated organs [ 44 ].

Total-body dynamic imaging and parametric imaging

The ultra-high time resolution and total-body coverage of the total-body PET/CT systems pave the way for total-body dynamic imaging, and enhance the image quality of parametric imaging [ 34 , 45 ]. Rausch et al. [ 19 ] demonstrated the feasibility of dynamic imaging for Biograph Vision Quadra PET/CT system with 10-min dynamic imaging of phantoms. Later, van Sluis et al. [ 46 ] generated 18 F-FDG net influx rate (Ki) images of 12 patients with suspected lung malignancy from a 65-min dynamic PET acquisition using the Quadra PET/CT system and 2 reconstruction settings and demonstrated good agreements between the two reconstruction approaches. Larsson et al. [ 47 ] estimated cerebral blood flow of 25 patients from a 60-min dynamic PET imaging using the Quadra PET/CT system and model‑free deconvolution approach. Li et al. [ 48 ] developed a deep learning approach to generate parametric images directly from the sinograms using Quadra PET/CT system, and the results demonstrated that high-quality Patlak Ki images could be generated based on the deep learning approach with high structural similarity and increased peak SNR. As for the PennPET Explorer, 18 F-fluortriopride and 30-min dynamic scan was performed for one subject, with images centered over the gallbladder. Representative images (1-min scans) demonstrated mild gallbladder emptying over time, underscoring the potential of the PennPET Explorer for dynamic imaging of multiple organs [ 18 ].

In terms of the uEXPLORER, Zhang et al. [ 49 ] developed a method to perform ultra-high temporal resolution dynamic PET imaging and visualized radiotracer transport across the entire body on timescales of 100-ms and obtained motion-frozen images with higher image quality compared to traditional methods. Sun et al. [ 50 ] demonstrated a frame-by-frame correction framework that can effectively reduce the effect of random body movements on dynamic images and the associated quantification process with overall quality improvement in quantitative Ki images. Wang et al. [ 51 ] developed a dual-time-window protocol based on the uEXPLORER, and reduced dynamic scanning time from 60 min to less than 20 min without affecting the diagnostic efficacy. The uEXPLORER also allows high-quality parametric imaging across the entire body, which can better characterize heterogeneous regional tracer kinetics than ROI-based analysis [ 52 ]. Zhang et al. developed quantitative parametric image reconstruction methods for kinetic analysis via uEXPLORER and demonstrated good image quality of dynamic images with low noise, even for the 1-s frames. In addition, there were excellent delineations of the smaller structures in cerebral, cardiac and vertebral regions [ 53 ]. Wang et al. performed 60-min total-body dynamic PET imaging for cancer patients and used voxel-wise compartmental model for parametric image reconstruction. Results showed improved lesion TAC fitting, physiologically more consistent vasculature in the fractional blood volume ( v b ) image, and improved tumor contrast (Fig.  2 d) [ 54 ]. In addition, parametric images can be potentially more useful than standardized uptake value (SUV) for liver tumor imaging and brain tumor imaging, as lesions are more visible with higher contrast on the Ki image than the SUV image [ 54 ].

In summary, despite the advantages of total-body PET systems in ultrafast, low-dose, and delayed imaging, combining these methods simultaneously may result in a decrease in image quality. Appropriate methods should be selected based on clinical needs, such as fast imaging for breath-holding lung imaging, low-dose imaging for children, and healthy individuals. While delayed imaging may require a higher radiation injection dose, which deserves careful consideration.

Research application of the total-body PET/CT systems

The advantages of the total-body PET/CT systems promise the applications [ 55 ]. Currently, research applications of the total-body PET/CT systems mainly involve tumor, nervous system, cardiovascular disease, and systemic immune diseases.

Application on the healthy participants

Due to radiation exposure, traditional PET/CT examination is generally used in the detection of tumors, and is not recommended for healthy individuals. However, the low-dose and ultra-low-dose imaging enabled by the total-body PET/CT systems have advanced the exploration of PET imaging in healthy individuals [ 56 ].

In 2020, Pantel et al. [ 18 ] demonstrated the ability to scan for a shorter duration using the PennPET Explorer scanner on healthy participants. Later, Zhang et al. [ 53 ] demonstrated the first total-body parametric imaging on a healthy volunteer via the uEXPLORER and demonstrated the spatiotemporal distribution of radiotracers in vivo in major organs/tissues (left ventricle, aorta, carotid artery, brachial artery, and femoral artery, myocardium, liver, gray matter, and white matter) (Fig.  3 ). Wang et al. [ 54 ] performed a 1-h dynamic scan after the injection of 370 MBq of 18 F-FDG on 5 healthy volunteers via the uEXPLORER and successfully conducted total-body PET multiparametric imaging and precise quantification of different organs using voxel-wise compartmental modeling strategies. Nardo et al. [ 42 ] performed dynamic scan after the injection of 370 MBq of 18 F-FDG on a 51-year-old healthy volunteer. The results showed significant reduction in blood pool activity at 3-h post-injection.

Dynamic PET/CT images of healthy volunteers. a Reconstructed dynamic PET images of early 3 min, 150–153 min, 300–303 min from a healthy male subject during and following an intravenous injection of 18 F-FDG using a dosing regimen of 1.85 MBq/kg [ 44 ]. b Reconstructed dynamic composite SUV images of early 10-min, mid 20-min, late 30-min scans of a healthy female subject during and following an intravenous injection of 4.57 MBq/kg of 18 F-FDG [ 53 ]. Dynamic PET/CT images from different sexes are for display purpose only

With increasing experience from total-body PET studies, uptake in normal physiologic structures becomes more prominent. For example, via total-body 18 F-FDG imaging, the adrenal glands, pituitary gland, and gray matter of the spinal cord are prominent [ 57 ]. Recently, Derlin et al. investigated vessel wall biology of healthy volunteers using the uEXPLORER with ultra-low-dose (0.185 MBq/kg) 18 F-FDG. Cross talk between vessel wall and lymphoid organs was identified with superior accuracy in total-body PET images, which might stimulate future mechanistic study or be used as biomarkers for monitoring vessel wall pathologies [ 58 ]. Lu et al. [ 59 ] demonstrated the in vivo glucose uptake and distribution across the human skeleton based on 18 F-FDG total-body PET scan using the uEXPLORER and further revealed that skeletal glucose uptake can be affected by age and dysregulated metabolism.

Application in oncology

The technical advantages of the total-body PET systems are beneficial to oncology studies. For example, with extended aFOV compared to short-axis PET scanner, the total-body PET system provides a platform to locate tumors across the entire body and evaluate tumor metastasis [ 60 ]. The high sensitivity offers better TACs of organs, providing a good tool to study tumor kinetics [ 49 , 61 ].

At present, total-body PET/CT scanners have been applied in the research of cancers in different organs, including the lung, liver, gut, and urogenital system. Figure  4 summarizes the clinical application of total-body PET/CT systems in cancer research.

Total-body PET images of different types of cancers. a Total-body PET images of a 58-year-old man with infiltrating adenocarcinoma of the lung confirmed by surgery. The FDG-avid lesion in the upper lobe of the right lung is identified in MIP and axial images with different reconstruction times [ 39 ]. The times in the panel represent reconstruction duration. b Coronal view of the estimated time delay t d map and K i parametric images with and without time delay correction (TDC) for a patient with liver cancer. Arrows point to the liver cancer [ 54 ]. To better illustrate the lesions in the liver, the authors only demonstrate the upper part of the total-body PET images. c MIP maps with different reconstruction times of a 58-year-old male with adenocarcinoma of the splenic flexure of the colon diagnosed by pathological examination. The corresponding axial images show a low-grade intraepithelial neoplasia lesion in the descending colon [ 40 ]. The times in the panel represent reconstruction duration. d Total-body dynamic FDG PET images of a patient with metastatic renal cancer. The MIP images demonstrate higher renal FDG uptake in the late phase than that in the early phase [ 54 ]. The times in the panel represent scan time

In terms of lung cancer, studies with both static and dynamic 18 F-FDG PET acquisition of patients with lung cancer using the Quadra PET/CT demonstrated that images with reduced scan time did not exhibit substantial loss of accuracy and precision [ 46 , 62 ]. Tan et al. [ 39 ] conducted half-dose (1.85 MBq/kg) and full-dose (3.70 MBq/kg) total-body PET scan of lung cancer patients, and demonstrated 100% lung cancer (primary and metastasis) detection rate via 2-min half-dose imaging (Fig.  4 a). Sun et al. [ 63 ] conducted network analysis at the systemic and organ level between lung cancer patients and healthy controls, and showed network deviations of lung cancer patients from the reference network.

As for liver cancer, a standard 18 F-FDG imaging protocol of 10 min was used via the Quadra scanner for oncological patients including recurrent hepatic cancer patient and scans were reconstructed at different time. The results showed improved lesion detection and classification while keeping the total scan time within 5 min [ 27 ]. Numerical simulations and preclinical scans both demonstrated clinically acceptable performance for detecting lesions in 1 min or less in the lung and liver via the prototype PennPET Explorer [ 33 , 64 ]. A total-body ultrafast scan (30–45-s) of liver cancer patients showed that image quality and lesion tumor-to-background ratio of PET images from the uEXPLORER were not significantly different from that of uMI 780 via a standard clinical protocol (Fig.  4 b) [ 35 , 54 ].

For colorectal cancer, a qualitative comparison study showed 18 F-FDG PennPET images to be of superior quality compared to traditional short-axis PET images with improvements in the delineation of sites of tumors for metastatic colon cancer when performed with similar scan durations [ 33 ]. An ultra-low-dose (0.37 MBq/kg) scan of colorectal cancer (CRC) patients via the uEXPLORER showed that the image quality of the 8-min group met the clinical diagnosis needs for CRC without affecting lesion detectability (Fig.  4 c) [ 40 ].

In terms of genitourinary cancer, Quadra PET/CT scanner demonstrated improved image quality, lesion quantification, and SNR in prostate cancer scanning compared to short-axis PET scanner [ 26 ]. A 60-min total-body dynamic scan performed to genitourinary cancer patients following the injection of 370 MBq of 18 F-FDG revealed all the lesions in SUV images. Improved TACs fitting, higher K i in lesions were observed in multiparametric images [ 54 ].

In addition, total-body PET/CT systems have also been used in studies of lymphomas, melanomas and sarcomas. Both ultrafast scan and low-dose scan have been performed for patients with lymphomas and melanomas via the Quadra scanner, and results demonstrated improved image quality and lesion detectability due to the higher sensitivity of the long aFOV scanner [ 37 , 62 , 65 , 66 ]. In the study by Chen et al., 100 pediatric oncological patients (including 9 infants) with lymphoma, rhabdomyosarcoma, and neuroblastoma underwent total-body PET/CT with half-dose (1.85 MBq/kg) 18 F-FDG. The results illustrated sufficient image quality and lesion conspicuity of the low-dose imaging in the assessment of sarcomas and lymphomas [ 36 ]. The study by Tang et al. [ 67 ] applied the uEXPLORER PET/CT on 105 pediatric lymphoma patients, and the results showed excellent performances for the uEXPLORER in the diagnosis of nodal, splenic, bone marrow, and other extranodal lymphoma involvement.

Cancer of unknown primary

Cancer of unknown primary (CUP) is difficult to treat, because existing therapeutics are predominantly specific to the primary tumor [ 68 , 69 ]. The total-body PET/CT scanner allows the assessment of multi-organ function (static PET imaging) and multi-organ interactions (dynamic PET imaging) across the entire body, which stands a chance to solve the issue of CUP [ 37 , 70 ].

In a case report of a patient with lymph node metastasis of an unknown primary tumor, Lu et al. [ 60 ] used static total-body PET scan to localize possible locations with abnormal FDG uptake and used dynamic total-body PET scan to find the metabolic similarities between the metastatic tumor and possible primary tumor locations. In a subject with metastatic colon cancer, 18 F-FDG PET imaging using the PennPET revealed an epiphrenic lymph node that was not obvious on clinical short-axis PET scan [ 33 ]. Wang et al. [ 54 ] found that in the same patient, multiple metastatic lesions showed similar TAC shapes and proved the value of dynamic imaging in the evaluation of metastatic tumors (Fig.  4 d).

Other applications

The concept of tissue perfusion is linked with blood flow, oxygen delivery, and a combination of blood flow and nutrition supply. Monitoring of tissue perfusion is an essential step in the management of many diseases [ 71 ]. With the advent of total-body PET, quantitative measurement of perfusion across the entire body is possible. A previous study estimated brain perfusion with five tracers including 15 O-H2O, 11 C-PIB, 18 F-FE-PE2I, 18 F-FDG, and 18 F-FET using dynamic imaging via the Quadra PET system [ 47 ]. A recent pilot study achieved total-body perfusion imaging with 11 C-Butanol on the uEXPLORER system, demonstrating the ability to obtain reproducible measurements of total-body perfusion with the total-body PET system [ 72 ].

In the past, PET-based studies have mainly focused on regional body parts. The advent of total-body PET systems makes it possible to detect whole-body systemic abnormalities [ 73 ]. Recently, Sun et al. developed a network analysis method for 18 F-FDG total-body PET images (Fig.  5 ). The developed method has been applied to assess metabolic abnormalities of individuals with lung cancer, gastrointestinal bleeding, and patients after suffering from Covid-19 disease and has revealed metabolic dysfunction from a systemic perspective [ 63 ].

Schematic diagram of the systemic metabolism network constructed via total-body SUV images and partial Pearson correlation coefficients. a 18 ROIs including 11 organs and 7 brain regions, according to Sun et al. [ 63 ]. b Illustration of group-level network analysis. c Illustration of individual-level network analysis. Based on the total-body uptake measures (i.e., SUV) images from multi-parameter information obtained by the uEXPLORER, systemic metabolic network can be constructed by calculating the partial Pearson partial correlation coefficient of the uptake measures between the two regions. The group-level differential network is calculated as the difference between the group-level networks of control and patient groups. In terms of individual-level differential network, a reference network of the control group is obtained, then a patient is added to the control group to form a new group, and a network of disturbance connections called the perturbation network is constructed using the same steps. The difference between the perturbation network and the reference network is labeled as the individual-level differential network to describe the deviated metabolic connectivity from the reference network. Abbreviations: RefNET, reference network; ConNET, control group network; PaNET, patient group network; PtbNET, perturbed network

The total-body PET systems also have the potential to contribute to the 89 Zr-antibody imaging exploration of immune diseases [ 70 ] and neurodegenerative disorders [ 74 ]. In addition, micro-dosing is one of the best approaches in pharmaceutical development since the low concentration of radiopharmaceutical exhibits lower toxicologic risks. The total-body PET/CT system with high sensitivity can provide a more precise estimate of pharmacokinetics and pharmacodynamic [ 75 ], contributing to the development of radiopharmaceuticals.

Clinical application of the total-body PET/CT systems

Compared with performance evaluation and research applications, there were fewer clinical instance for the total-body PET systems. Currently, the main clinical application is in the oncology, and there are three types of tracers used in clinical total-body PET scans, including 18 F-FDG, 18 F-Fluciclovine, and 68 Ga-DOTATATE [ 42 ]. For the 18 F-FDG and 68 Ga-DOTATATE, according to the experience at University of California, Davis, the recommended scan protocol is 20-min scan at 2 h post-injection with 296 MBq (8 mCi) of 18 F-FDG or 68 Ga-DOTATATE. The recommended protocol for the 18 F-Fluciclovine is 25-min scan at the time of injection with doses ranging from 185 MBq (5 mCi) to 296 MBq (8 mCi) [ 42 ].

Total-body PET/CT is also becoming an effective imaging tool in the diagnosis of complicated diseases. Wang et al. revealed the internal relationship of pancreatic disease, pancreatic lipid membrane inflammation and polyarthritis in panniculitis, polyarthritis, and pancreatitis syndrome (PPP) at the molecular imaging level based on the uEXPLORER total-body PET/CT imaging in a patient diagnosed with multiple metastases of pancreatic cancer associated with pancreatic lipid membranitis, avoiding the high mortality associated with delayed diagnosis of PPP [ 76 ]. Total-body PET systems also enable accurate assessment of rheumatic immune disease at systemic level and can help to distinguish rheumatoid immune diseases from tumors, lymphomas, or identify the primary tumor lesions that cause arthritic manifestations [ 77 , 78 ].

• Deep learning

The combination of the total-body PET imaging with machine learning techniques, especially deep learning, may have the potential to solve practical problems that exist in current PET applications [ 79 , 80 ].

Since analytical reconstruction methods may generate images with a high level of noise, and iterative methods are time-consuming for total-body PET image reconstruction [ 81 ], deep learning-based methods have been applied for total-body PET image reconstruction. Ma et al. [ 81 ] proposed an encoder-decoder network and achieved reconstruction of total-body PET images on sinograms from the Quadra PET system. Using ultra-high-quality PET images from uEXPLORER, Wang et al. [ 82 ] developed a deep progressive learning (DPL) image reconstruction method and verified that the algorithm could reduce the injection dose by 66% without the loss of image quality and even outperformed the traditional algorithm with full dose for small lesion visualization. Yang et al. [ 83 ] proposed a DPL method for PET image reconstruction. The network was trained with high-quality PET images from the uEXPLORER and was then incorporated into an iterative reconstruction process, which bridges the gap between low-quality and high-quality images, resulting in better contrast for small lesions.

For tracer kinetic modeling, an image-derived input function (IDIF) is often extracted from an ROI selected within a large blood pool [ 84 , 85 ]. However, for peripheral tissue region, the arrival time of the radiotracer is delayed compared with the start time of the extracted blood input function [ 86 ]. Wang et al. [ 86 ] have constructed a deep learning-based regression model that can estimate time delay and/or dispersion of the blood input from the tissue TAC data in combination with the blood input function. In addition, the IDIF represents the tracer activity in the whole blood, a plasma input function is what is actually needed [ 84 , 85 ]. Deep learning has the potential to predict the input function from tissue TACs. For instance, Kuttner et al. [ 87 ] estimated the IDIF from multiple blood pool TACs or multiple tissue TACs using a Gaussian process model and long short-term memory network. Wang et al. [ 88 ] used deep learning to estimate IDIF directly from dynamic images instead of from manually placed ROIs.

In terms of parametric imaging, K i provides equivalent or superior lesion detectability in comparison with SUV [ 89 ]. However, parametric imaging takes a long acquisition time to generate K i images [ 90 ]. Several studies have demonstrated that deep learning has the potential to generate parametric images from static PET images and is robust to noise [ 91 , 92 ]. Huang et al. proposed a fast deep learning method with static SUV images via the uEXPLORER system as the input, and Patlak Ki images as the ground truth. The trained model can generate total-body parametric Ki images without an IDIF [ 90 ]. Li et al. [ 48 ] configured a deep learning framework called DeepPET and reconstructed a high-quality direct Patlak Ki image from five-frame sinograms via the Quadra system without input function.

In addition, using the powerful mapping ability of deep learning algorithms and the training data from the total-body PET scanners is one way to overcome hardware limitations of short-axis PET scanners [ 93 ]. Shang et al. proposed a supervised deep learning model based on a cycle-consistent generative adversarial network (CycleGAN). Trained using data from uEXPLORER, CycleGAN was able to improve the image quality of PET scanners with 320 mm aFOV or even shorter aFOVs [ 93 ].

In summary, the introduction of deep learning algorithms not only solved general medical imaging problems including image reconstruction and kinetics modeling [ 90 ], but also improved the performances of traditional short-axis PET systems with algorithms specifically designed using training data from the uEXPLORER [ 82 , 83 ]. However, the existing total-body PET imaging datasets is relatively small, which may limit the development of total-body PET-based deep learning models. With the enrichment of total-body PET datasets in the future, deep learning models based on the total-body PET systems will become more accurate and efficient [ 86 ].

Discussions and conclusions

The total-body PET system, as the most advanced molecular imaging platform for the human body, extends the aFOV to above 1 m [ 1 , 7 , 8 , 20 ]. In this review, we have collected and summarized technical reports and studies using the three total-body PET systems in the PubMed database over the past 5 years. Among the three existing systems, the uEXPLORER and Biograph Vision Quadra have been commercially available, and have already been applied in clinical practice, while the PennPET Explorer has not been commercially available.

In general, the hardware upgrade of the three total-body PET systems increases the sensitivity of the systems, allowing for ultrafast [ 18 , 26 , 29 , 33 , 34 , 35 , 36 ], low-dose [ 37 , 38 , 39 , 40 , 41 ], delayed, and dynamic imaging [ 18 , 46 , 47 , 48 , 49 , 50 , 51 ]. Due to the upgraded of the total-body PET system, its applications are also expanding, which includes but not limited to the diagnosis of tumor, tumor metastasis, rare diseases, and immunological disorders [ 35 , 39 , 40 , 54 , 64 , 65 , 66 , 70 , 71 , 72 , 76 ]. Moreover, based on the total-body PET systems, researchers have developed deep learning models for generating parametric images, and models that can improve image quality of conventional short-axis PET systems [ 81 , 82 , 83 , 86 , 90 , 93 ].

The technical advantages of the total-body PET systems enable the applications for many research purposes, well beyond the applications mentioned above. However, most current studies have been focused on the performance evaluation such as reduced scan time or reduced radiopharmaceutical doses, and little attention has been paid to the clinical aspect of the diseases. Specifically, studies on systemic metabolic diseases and tumor metastases, which involve multiple organs and tissues across the human body, are currently available only in few cases mentioned in this review [ 54 , 60 , 76 ]. The 4-dimensional (4D) data acquired from dynamic PET may reflect a broad spectrum of physiological information, including blood flow, tracer delivery, transport, and metabolism [ 86 ]. However, current dynamic PET studies via the total-body systems have been limited to single organ analysis, such as the brain and heart [ 47 , 53 ]. Total-body dynamic imaging studies are still lacking. Future total-body PET imaging studies should pay more attention to on physiological and biologically relevant assays such as cerebral blood volume, blood flow, glucose metabolism, oxygen utilization, DNA synthesis, signal transduction, cancer cell phenotyping for molecularly targeted therapies, pharmacokinetics, pharmacodynamics, etc., to assist in the diagnosis of diseases [ 94 ].

In addition, the sample size of existing studies was generally small, and future studies with larger sample sizes are needed. Regarding machine leaning, various deep learning algorithms can effectively improve the performance of total-body PET systems, but the combination of total-body PET systems and deep learning is currently in its infancy due to limited number of total-body PET imaging datasets. Lastly, since total-body PET/CT images can be rendered to show the subject’s face and body, privacy concerns have arisen [ 95 ]. Selfridge et al. [ 95 ] developed a method that obscures a subject’s face in 3-dimensional volumetric data, which is recommended when sharing total-body PET imaging data.

In conclusion, since living organisms maintain homeostasis through dynamic multi-organ interactions, the total-body PET offers unique opportunities to investigate multi-organ interactions for the understanding of human physiology and pathology [ 73 ]. As the prosper of total-body PET-based studies and the enrichment of research data, they can serve as an invaluable tool for elucidating underlying biology across the human body, opening new path for innovative research in physiology, biochemistry, and pharmacology [ 49 ]. In precision medicine, the total-body PET systems stand a chance to identify metastases of inflammation, infection and cancer throughout the body and assist doctors to develop precise treatment plans. In drug development, it will enable whole-body pharmacokinetic examinations to observe dynamic uptake of drugs in each organ and tissue in vivo, thus significantly shortening the drug development process. In a word, the total-body PET will certainly push the existing boundaries of PET imaging and make a greater contribution in many medical fields.

Availability of data and materials

Not applicable.

Abbreviations

Computed tomography

Axial field of view

Convolutional neural network

Colorectal cancer

Fluorodeoxyglucose

Positron emission tomography

Signal-to-noise ratio

Standardized uptake value normalized by lean body mass

Standardized uptake value

Time-activity curve

Surti S, Pantel AR, Karp JS. Total body PET: why, how, what for? IEEE Trans Radiat Plasma Med Sci. 2020;4(3):283–92.

Article   PubMed   PubMed Central   Google Scholar  

Kinahan PE, Townsend DW, Beyer T, Sashin D. Attenuation correction for a combined 3D PET/CT scanner. Med Phys. 1998;25(10):2046–53.

Article   CAS   PubMed   Google Scholar  

Basu S, Hess S, Nielsen Braad PE, Olsen BB, Inglev S, Høilund-Carlsen PF. The basic principles of FDG-PET/CT imaging. PET Clin. 2014;9(4):355–70.

Article   PubMed   Google Scholar  

Leung EK, Judenhofer MS, Cherry SR, Badawi RD. Performance assessment of a software-based coincidence processor for the EXPLORER total-body PET scanner. Phys Med Biol. 2018;63(18):18NT01.

Uzuegbunam BC, Librizzi D, Hooshyar YB. PET radiopharmaceuticals for Alzheimer’s disease and Parkinson’s disease diagnosis, the current and future landscape. Molecules. 2020;25(4):977.

Article   CAS   PubMed   PubMed Central   Google Scholar  

Parent EE, Schuster DM. Update on 18F-fluciclovine PET for prostate cancer imaging. J Nucl Med. 2018;59(5):733–9.

Vandenberghe S, Moskal P, Karp JS. State of the art in total body PET. EJNMMI Phys. 2020;7(1):35.

Nadig V, Herrmann K, Mottaghy FM, Schulz V. Hybrid total-body pet scanners-current status and future perspectives. Eur J Nucl Med Mol Imaging. 2022;49(2):445–59.

Sartini L, Simeone F, Pani P, Bue NL, Marinaro G, Grubich A, Lobko A, Etiope G, Capone A, Favali P, Gasparoni F. GEMS: underwater spectrometer for long-term radioactivity measurements. Nucl Instrum Methods Phys Res Sect A Accel Spectrom Detect Assoc Equip. 2011;626–627:S145–7.

Article   Google Scholar  

Bisogni MG, Morrocchi M. Development of analog solid-state photo-detectors for positron emission tomography. Nucl Instrum Methods Phys Res Sect A Accel Spectrom Detect Assoc Equip. 2016;809:140–8.

Article   CAS   Google Scholar  

Jarron P, Auffray E, Brunner S E, et al. Time based readout of a silicon photomultiplier (SiPM) for Time Of Flight Positron Emission Tomography (TOF-PET). In: Nuclear science symposium conference record (NSS/MIC), 2009 IEEE. IEEE; 2009.

Surti S, Karp JS. Advances in time-of-flight PET. Phys Med. 2016;32(1):12–22.

Otte A, Barral J, Dolgoshein B, et al. A test of silicon photomultipliers as readout for PET. Nucl Instrum Methods Phys Res. 2005;545(3):705–15.

Newport DF, Siegel SB, Swann BK, et al. QuickSilver (TM): a flexible, extensible, and high-speed architecture for multi-modality imaging. In: Nuclear science symposium conference record, 2006. IEEE. IEEE; 2006.

Karakatsanis NA, Zhou Y, Lodge MA, Casey ME, Wahl RL, Zaidi H, Rahmim A. Generalized whole-body Patlak parametric imaging for enhanced quantification in clinical PET. Phys Med Biol. 2015;60(22):8643–73.

Muzic RF Jr, DiFilippo FP. Positron emission tomography-magnetic resonance imaging: technical review. Semin Roentgenol. 2014;49(3):242–54.

Townsend D, et al. Basic science of PET and PET/CT. In: Valk P, Bailey D, Townsend D, et al., editors. Positron emission tomography. London: Springer; 2006. p. 1–16.

Google Scholar  

Pantel AR, Viswanath V, Karp JS. Update on the PennPET explorer: a whole-body imager with scalable axial field-of-view. PET Clin. 2021;16(1):15–23.

Rausch I, Mannheim JG, Kupferschläger J, la Fougère C, Schmidt FP. Image quality assessment along the one metre axial field-of-view of the total-body Biograph Vision Quadra PET/CT system for 18F-FDG. EJNMMI Phys. 2022;9(1):87.

Ng QK, Triumbari EKA, Omidvari N, Cherry SR, Badawi RD, Nardo L. Total-body PET/CT: first clinical experiences and future perspectives. Semin Nucl Med. 2022;52(3):330–9.

Altunay B, Morgenroth A, Beheshti M, Vogg A, Wong NCL, Ting HH, Biersack HJ, Stickeler E, Mottaghy FM. HER2-directed antibodies, affibodies and nanobodies as drug-delivery vehicles in breast cancer with a specific focus on radioimmunotherapy and radioimmunoimaging. Eur J Nucl Med Mol Imaging. 2021;48(5):1371–89.

Spencer BA, Berg E, Schmall JP, Omidvari N, Leung EK, Abdelhafez YG, Tang S, Deng Z, Dong Y, Lv Y, Bao J, Liu W, Li H, Jones T, Badawi RD, Cherry SR. Performance evaluation of the uEXPLORER total-body PET/CT scanner based on NEMA NU 2–2018 with additional tests to characterize PET scanners with a long axial field of view. J Nucl Med. 2021;62(6):861–70.

Lan X, Fan K, Li K, Cai W. Dynamic PET imaging with ultra-low-activity of 18F-FDG: unleashing the potential of total-body PET. Eur J Nucl Med Mol Imaging. 2021;48(13):4138–41.

Zhang X, Badawi RD, Cherry SR, Qi J. Theoretical study of the benefit of long axial field-of-view PET on region of interest quantification. Phys Med Biol. 2018;63(13):135010.

Daube-Witherspoon ME, Viswanath V, Werner ME, Karp JS. Performance characteristics of long axial field-of-view PET scanners with axial gaps. IEEE Trans Radiat Plasma Med Sci. 2021;5(3):322–30.

Alberts I, Hünermund JN, Prenosil G, et al. Clinical performance of long axial field of view PET/CT: a head-to-head intra-individual comparison of the Biograph Vision Quadra with the Biograph Vision PET/CT. Eur J Nucl Med Mol Imaging. 2021;48(8):2395–404.

Honoré d’Este S, Andersen FL, Andersen JB, et al. Potential clinical impact of LAFOV PET/CT: a systematic evaluation of image quality and lesion detection. Diagnostics. 2023;13(21):3295.

Prenosil GA, Sari H, Fürstner M, et al. Performance characteristics of the Biograph Vision Quadra PET/CT system with a long axial field of view using the NEMA NU 2–2018 standard. J Nucl Med. 2022;63(3):476–84.

Cherry SR, Badawi RD, Karp JS, Moses WW, Price P, Jones T. Total-body imaging: transforming the role of positron emission tomography. Sci Transl Med. 2017;9(381):eaaf6169.

Cherry SR, Jones T, Karp JS, Qi J, Moses WW, Badawi RD. Total-body PET: maximizing sensitivity to create new opportunities for clinical research and patient care. J Nucl Med. 2018;59(1):3–12.

Dai B, Daube-Witherspoon ME, McDonald S, et al. Performance evaluation of the PennPET explorer with expanded axial coverage. Phys Med Biol. 2023;68(9):095007.

Article   PubMed Central   Google Scholar  

Leung EK, Berg E, Omidvari N, Spencer BA, Li E, Abdelhafez YG, Schmall JP, Liu W, He L, Tang S, Liu Y, Dong Y, Jones T, Cherry SR, Badawi RD. Quantitative accuracy in total-body imaging using the uEXPLORER PET/CT scanner. Phys Med Biol. 2021. https://doi.org/10.1088/1361-6560/ac287c .

Pantel AR, Viswanath V, Daube-Witherspoon ME, et al. PennPET explorer: human imaging on a whole-body imager. J Nucl Med. 2020;61(1):144–51.

Nardo L, Pantel AR. Oncologic applications of long axial field-of-view PET/computed tomography. PET Clin. 2021;16(1):65–73.

Hu P, Zhang Y, Yu H, Chen S, Tan H, Qi C, Dong Y, Wang Y, Deng Z, Shi H. Total-body 18F-FDG PET/CT scan in oncology patients: how fast could it be? Eur J Nucl Med Mol Imaging. 2021;48(8):2384–94.

Chen W, Liu L, Li Y, Li S, Li Z, Zhang W, Zhang X, Wu R, Hu D, Sun H, Zhou Y, Fan W, Zhao Y, Zhang Y, Hu Y. Evaluation of pediatric malignancies using total-body PET/CT with half-dose [18F]-FDG. Eur J Nucl Med Mol Imaging. 2022;49(12):4145–55.

Sachpekidis C, Pan L, Kopp-Schneider A, Weru V, Hassel JC, Dimitrakopoulou-Strauss A. Application of the long axial field-of-view PET/CT with low-dose [18F]FDG in melanoma. Eur J Nucl Med Mol Imaging. 2023;50(4):1158–67.

Viswanath V, Pantel AR, Daube-Witherspoon ME, et al. Quantifying bias and precision of kinetic parameter estimation on the PennPET Explorer, a long axial field-of-view scanner. IEEE Trans Radiat Plasma Med Sci. 2020;4(6):735–49.

Tan H, Sui X, Yin H, Yu H, Gu Y, Chen S, Hu P, Mao W, Shi H. Total-body PET/CT using half-dose FDG and compared with conventional PET/CT using full-dose FDG in lung cancer. Eur J Nucl Med Mol Imaging. 2021;48(6):1966–75.

Tan H, Cai D, Sui X, Qi C, Mao W, Zhang Y, Liu G, Yu H, Chen S, Hu P, Gu J, Shi H. Investigating ultra-low-dose total-body [18F]-FDG PET/CT in colorectal cancer: initial experience. Eur J Nucl Med Mol Imaging. 2022;49(3):1002–11.

Zhao YM, Li YH, Chen T, Zhang WG, Wang LH, Feng J, Li C, Zhang X, Fan W, Hu YY. Image quality and lesion detectability in low-dose pediatric 18F-FDG scans using total-body PET/CT. Eur J Nucl Med Mol Imaging. 2021;48(11):3378–85.

Nardo L, Abdelhafez YG, Spencer BA, Badawi RD. Clinical implementation of total-body PET/CT at University of California. Davis PET Clin. 2021;16(1):1–7.

Schmall JP, Karp JS, Alavi A. The potential role of total body PET imaging in assessment of atherosclerosis. PET Clin. 2019;14(2):245–50.

Hu P, Lin X, Zhuo W, Tan H, Xie T, Liu G, Chen S, Chen X, Yu H, Zhang Y, Shi H, Liu H. Internal dosimetry in F-18 FDG PET examinations based on long-time-measured organ activities using total-body PET/CT: does it make any difference from a short-time measurement? EJNMMI Phys. 2021;8(1):51.

Phelps ME. Positron emission tomography provides molecular imaging of biological processes. Proc Natl Acad Sci USA. 2000;97(16):9226–33.

van Sluis J, van Snick JH, Brouwers AH, et al. Shortened duration whole body 18F-FDG PET Patlak imaging on the Biograph Vision Quadra PET/CT using a population-averaged input function. EJNMMI Phys. 2022;9(1):74.

Larsson HBW, Law I, Andersen TL, et al. Brain perfusion estimation by Tikhonov model-free deconvolution in a long axial field of view PET/CT scanner exploring five different PET tracers. Eur J Nucl Med Mol Imaging. 2023. https://doi.org/10.1007/s00259-023-06469-w .

Li Y, Hu J, Sari H, et al. A deep neural network for parametric image reconstruction on a large axial field-of-view PET. Eur J Nucl Med Mol Imaging. 2023;50(3):701–14.

Zhang X, Cherry SR, Xie Z, Shi H, Badawi RD, Qi J. Subsecond total-body imaging using ultrasensitive positron emission tomography. Proc Natl Acad Sci USA. 2020;117(5):2265–7.

Sun T, Wu Y, Wei W, Fu F, Meng N, Chen H, Li X, Bai Y, Wang Z, Ding J, Hu D, Chen C, Hu Z, Liang D, Liu X, Zheng H, Yang Y, Zhou Y, Wang M. Motion correction and its impact on quantification in dynamic total-body 18F-fluorodeoxyglucose PET. EJNMMI Phys. 2022;9(1):62.

Wang Z, Wu Y, Li X, Bai Y, Chen H, Ding J, Shen C, Hu Z, Liang D, Liu X, Zheng H, Yang Y, Zhou Y, Wang M, Sun T. Comparison between a dual-time-window protocol and other simplified protocols for dynamic total-body 18F-FDG PET imaging. EJNMMI Phys. 2022;9(1):63.

Wu Y, Feng T, Zhao Y, Xu T, Fu F, Huang Z, Meng N, Li H, Shao F, Wang M. Whole-body parametric imaging of 18F-FDG PET using uEXPLORER with reduced scanning time. J Nucl Med. 2022;63(4):622–8.

Zhang X, Xie Z, Berg E, Judenhofer MS, Liu W, Xu T, Ding Y, Lv Y, Dong Y, Deng Z, Tang S, Shi H, Hu P, Chen S, Bao J, Li H, Zhou J, Wang G, Cherry SR, Badawi RD, Qi J. Total-body dynamic reconstruction and parametric imaging on the uEXPLORER. J Nucl Med. 2020;61(2):285–91.

Wang G, Nardo L, Parikh M, Abdelhafez YG, Li E, Spencer BA, Qi J, Jones T, Cherry SR, Badawi RD. Total-body PET multiparametric imaging of cancer using a voxelwise strategy of compartmental modeling. J Nucl Med. 2022;63(8):1274–81.

Surti S, Karp JS. Impact of detector design on imaging performance of a long axial field-of-view, whole-body PET scanner. Phys Med Biol. 2015;60(13):5343–58.

Donaldson K, Buchanich JM, Grigson PS. Abstracts of presentations at the association of clinical scientists 143rd meeting Louisville, KY May 11–14, 2022. Ann Clin Lab Sci. 2022;52(3):511–25.

ECR 2020 Book of Abstracts: Vienna, Austria. 15 March 2020. Insights Imaging. 2020;11(Suppl 1):34.

Derlin T, Spencer BA, Mamach M, Abdelhafez Y, Nardo L, Badawi RD, Cherry SR, Bengel FM. Exploring vessel wall biology in vivo by ultra-sensitive total-body positron emission tomography. J Nucl Med. 2022;64:416–22.

Lu W, Duan Y, Li K, Qiu J, Cheng Z. Glucose uptake and distribution across the human skeleton using state-of-the-art total-body PET/CT. Bone Res. 2023;11(1):36.

Lu W, Qiu J, Xie X, Li K, Duan Y, Li M, Ma C, Cheng Z, Liu S. Recognizing tumor origin for lymphoid tumor of unknown primary via total-body PET/CT scan-case report. Front Oncol. 2022;12:766490.

Badawi RD, Shi H, Hu P, Chen S, Xu T, Price PM, Ding Y, Spencer BA, Nardo L, Liu W, Bao J, Jones T, Li H, Cherry SR. First human imaging studies with the EXPLORER total-body PET scanner. J Nucl Med. 2019;60(3):299–303.

Mingels C, Weidner S, Sari H, et al. Impact of the new ultra-high sensitivity mode in a long axial field-of-view PET/CT. Ann Nucl Med. 2023;37(5):310–5.

Sun T, Wang Z, Wu Y, Gu F, Li X, Bai Y, Shen C, Hu Z, Liang D, Liu X, Zheng H, Yang Y, El Fakhri G, Zhou Y, Wang M. Identifying the individual metabolic abnormities from a systemic perspective using whole-body PET imaging. Eur J Nucl Med Mol Imaging. 2022;49(8):2994–3004.

Viswanath V, Daube Witherspoon ME, Karp JS, Surti S. Numerical observer study of lesion detectability for a long axial field-of-view whole-body PET imager using the PennPET Explorer. Phys Med Biol. 2020;65(3):035002.

Calderón E, Schmidt FP, Lan W, et al. Image quality and quantitative PET parameters of low-dose [18F]FDG PET in a long axial field-of-view PET/CT scanner. Diagnostics. 2023;13(20):3240.

Korsholm K, Overbeck N, Dias AH, Loft A, Andersen FL, Fischer BM. Impact of reduced image noise on deauville scores in patients with lymphoma scanned on a long-axial field-of-view PET/CT-scanner. Diagnostics. 2023;13(5):947.

Tang S, Hu Y, Zeng J, Li Z, Jiang Y, Li Y, Wang J, Sun H, Wu X, Zhou Y, Zhang X, Zhao Y. Significant CT dose reduction of 2-[18F]FDG PET/CT in pretreatment pediatric lymphoma without compromising the diagnostic and staging efficacy. Eur Radiol. 2022;33:2248–57.

Mehlen P, Puisieux A. Metastasis: a question of life or death. Nat Rev Cancer. 2006;6(6):449–58.

Lu MY, Chen TY, Williamson DFK, Zhao M, Shady M, Lipkova J, Mahmood F. AI-based pathology predicts origins for cancers of unknown primary. Nature. 2021;594(7861):106–10.

Mohr P, van Sluis J, Providência L, et al. Long versus short axial field of view immuno-PET/CT: semiquantitative evaluation for 89Zr-trastuzumab. J Nucl Med. 2023;64(11):1815–20.

Hasanin A, Mukhtar A, Nassar H. Perfusion indices revisited. J Intensive Care. 2017;5:24.

Li EJ, López JE, Spencer BA, et al. Total-body perfusion imaging with [11C]-butanol. J Nucl Med. 2023;64(11):1831–8.

Shiyam Sundar LK, Hacker M, Beyer T. Whole-body PET imaging: a catalyst for whole-person research? J Nucl Med. 2023;64(2):197–9.

Xin M, Li L, Wang C, Shao H, Liu J, Zhang C. Pilot study on 11C-CFT dynamic imaging using total-body PET/CT: biodistribution and radiation dosimetry in Parkinson’s disease. Front Neurol. 2023;14:1153779.

Wei W, Jiang D, Ehlerding EB, Luo Q, Cai W. Noninvasive PET imaging of T cells. Trends Cancer. 2018;4(5):359–73.

Wang X, Cheng Z. Nodules on the lower legs with ankle joint pain. Gastroenterology. 2021;161(5):1390–2.

Abdelhafez Y, Raychaudhuri SP, Mazza D, Sarkar S, Hunt HL, McBride K, Nguyen M, Caudle DT, Spencer BA, Omidvari N, Bang H, Cherry SR, Nardo L, Badawi RD, Chaudhari AJ. Total-body 18F-FDG PET/CT in autoimmune inflammatory arthritis at ultra-low dose: initial observations. J Nucl Med. 2022;63(10):1579–85.

Chaudhari AJ, Raynor WY, Gholamrezanezhad A, Werner TJ, Rajapakse CS, Alavi A. Total-body PET imaging of musculoskeletal disorders. PET Clin. 2021;16(1):99–117.

Domingues I, Pereira G, Martins P, Duarte H, Santos J, Abreu PH. Using deep learning techniques in medical imaging: a systematic review of applications on CT and PET. Artif Intell Rev. 2020;53(6):4093–160.

Gong K, Berg E, Cherry SR, Qi J. Machine learning in PET: from photon detection to quantitative image reconstruction. Proc IEEE. 2020;108(1):51–68.

Ma R, Hu J, Sari H, et al. An encoder-decoder network for direct image reconstruction on sinograms of a long axial field of view PET. Eur J Nucl Med Mol Imaging. 2022;49(13):4464–77.

Wang T, Qiao W, Wang Y, Wang J, Lv Y, Dong Y, Qian Z, Xing Y, Zhao J. Deep progressive learning achieves whole-body low-dose 18F-FDG PET imaging. EJNMMI Phys. 2022;9(1):82.

Lv Y, Xi C. PET image reconstruction with deep progressive learning. Phys Med Biol. 2021;66(10):105016.

Feng T, Zhao Y, Shi H, Li H, Zhang X, Wang G, Price PM, Badawi RD, Cherry SR, Jones T. Total-body quantitative parametric imaging of early kinetics of 18F-FDG. J Nucl Med. 2021;62(5):738–44.

Wang G, Corwin MT, Olson KA, Badawi RD, Sarkar S. Dynamic PET of human liver inflammation: impact of kinetic modeling with optimization-derived dual-blood input function. Phys Med Biol. 2018;63(15):155004.

Wang Y, Li E, Cherry SR, Wang G. Total-body PET kinetic modeling and potential opportunities using deep learning. PET Clin. 2021;16(4):613–25.

Kuttner S, Wickstrøm KK, Lubberink M, Tolf A, Burman J, Sundset R, Jenssen R, Appel L, Axelsson J. Cerebral blood flow measurements with 15O-water PET using a non-invasive machine-learning-derived arterial input function. J Cereb Blood Flow Metab. 2021;41(9):2229–41.

Wang L, Ma T, Yao S, et al. Direct estimation of input function based on fine-tuned deep learning method in dynamic PET imaging. J Nucl Med. 2020;61(supplement 1):1394–1394.

Zaker N, Kotasidis F, Garibotto V, Zaidi H. Assessment of lesion detectability in dynamic whole-body PET imaging using compartmental and patlak parametric mapping. Clin Nucl Med. 2020;45(5):e221–31.

Huang Z, Wu Y, Fu F, Meng N, Gu F, Wu Q, Zhou Y, Yang Y, Liu X, Zheng H, Liang D, Wang M, Hu Z. Parametric image generation with the uEXPLORER total-body PET/CT system through deep learning. Eur J Nucl Med Mol Imaging. 2022;49(8):2482–92.

Pan L, Cheng C, Haberkorn U, Dimitrakopoulou-Strauss A. Machine learning-based kinetic modeling: a robust and reproducible solution for quantitative analysis of dynamic PET data. Phys Med Biol. 2017;62(9):3566–81.

Wang B, Ruan D, Liu H. Noninvasive estimation of macro-parameters by deep learning. IEEE Trans Radiat Plasma Med Sci. 2020;4(6):684–95.

Shang C, Zhao G, Li Y, Yuan J, Wang M, Wu Y, Lin Y. Short-axis PET image quality improvement by attention CycleGAN using total-body PET. J Healthc Eng. 2022;2022:4247023.

Cherry SR, Sorenson J, Phelps ME, et al. Tracer kinetic modeling. In: Phelps ME, et al., editors. Physics in nuclear medicine. 3rd ed. Elsevier: Philadelphia; 2003. p. 377–403.

Selfridge AR, Spencer BA, Abdelhafez YG, Nakagawa K, Tupin JD, Badawi RD. Facial anonymization and privacy concerns in total-body PET/CT. J Nucl Med. 2023;64(8):1304–9.

Download references

Acknowledgements

This work was supported by the Science and Technology Funding from Jinan (Grant Number: 2020GXRC018), Academic Promotion Program of Shandong First Medical University (Grant Number: 2019QL009), and Taishan Scholars Program of Shandong Province (Grant Number: TS201712065).

Author information

Authors and affiliations.

Department of Radiology, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, 271016, China

Yuanyuan Sun & Jianfeng Qiu

Department of PET-CT, The First Affiliated Hospital of Shandong First Medical University, Shandong Provincial Qianfoshan Hospital Affiliated to Shandong University, Jinan, 250014, China

Zhaoping Cheng

Department of Radiology, The Second Affiliated Hospital of Shandong First Medical University, No. 366 Taishan Street, Taian, 271000, China

You can also search for this author in PubMed   Google Scholar

Contributions

YS and ZC collected the studies and wrote the draft of the manuscript. JQ contributed to literature arrangement. WL reviewed the manuscript.

Corresponding author

Correspondence to Weizhao Lu .

Ethics declarations

Ethics approval and consent to participate.

This is a review article; therefore, ethical approval is not applicable.

Consent to participate

Consent to publish.

We have obtained permissions to reproduce Figs.  2 , 3 and 4 .

Competing interests

The authors have no conflicts of interest to declare that are relevant to the content of this article.

Additional information

Publisher's note.

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ .

Reprints and permissions

About this article

Cite this article.

Sun, Y., Cheng, Z., Qiu, J. et al. Performance and application of the total-body PET/CT scanner: a literature review. EJNMMI Res 14 , 38 (2024). https://doi.org/10.1186/s13550-023-01059-1

Download citation

Received : 08 October 2023

Accepted : 14 December 2023

Published : 12 April 2024

DOI : https://doi.org/10.1186/s13550-023-01059-1

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

• Total-body PET/CT
• Performance evaluation
• Clinical application