example of related studies in thesis

Review of Related Literature: Format, Example, & How to Make RRL

A review of related literature is a separate paper or a part of an article that collects and synthesizes discussion on a topic. Its purpose is to show the current state of research on the issue and highlight gaps in existing knowledge. A literature review can be included in a research paper or scholarly article, typically following the introduction and before the research methods section.

This article will clarify the definition, significance, and structure of a review of related literature. You’ll also learn how to organize your literature review and discover ideas for an RRL in different subjects.

🔤 What Is RRL?

• ❗ Significance of Literature Review
• 🔎 How to Search for Literature
• 🧩 Literature Review Structure
• 📋 Format of RRL — APA, MLA, & Others
• ✍️ How to Write an RRL
• 📚 Examples of RRL

🔗 References

A review of related literature (RRL) is a part of the research report that examines significant studies, theories, and concepts published in scholarly sources on a particular topic. An RRL includes 3 main components:

• A short overview and critique of the previous research.
• Similarities and differences between past studies and the current one.
• An explanation of the theoretical frameworks underpinning the research.

❗ Significance of Review of Related Literature

Although the goal of a review of related literature differs depending on the discipline and its intended use, its significance cannot be overstated. Here are some examples of how a review might be beneficial:

• It helps determine knowledge gaps .
• It saves from duplicating research that has already been conducted.
• It provides an overview of various research areas within the discipline.
• It demonstrates the researcher’s familiarity with the topic.

🔎 How to Perform a Literature Search

Including a description of your search strategy in the literature review section can significantly increase your grade. You can search sources with the following steps:

🧩 Literature Review Structure Example

The majority of literature reviews follow a standard introduction-body-conclusion structure. Let’s look at the RRL structure in detail.

Introduction of Review of Related Literature: Sample

An introduction should clarify the study topic and the depth of the information to be delivered. It should also explain the types of sources used. If your lit. review is part of a larger research proposal or project, you can combine its introductory paragraph with the introduction of your paper.

Here is a sample introduction to an RRL about cyberbullying:

Bullying has troubled people since the beginning of time. However, with modern technological advancements, especially social media, bullying has evolved into cyberbullying. As a result, nowadays, teenagers and adults cannot flee their bullies, which makes them feel lonely and helpless. This literature review will examine recent studies on cyberbullying.

Sample Review of Related Literature Thesis

A thesis statement should include the central idea of your literature review and the primary supporting elements you discovered in the literature. Thesis statements are typically put at the end of the introductory paragraph.

Look at a sample thesis of a review of related literature:

This literature review shows that scholars have recently covered the issues of bullies’ motivation, the impact of bullying on victims and aggressors, common cyberbullying techniques, and victims’ coping strategies. However, there is still no agreement on the best practices to address cyberbullying.

Literature Review Body Paragraph Example

The main body of a literature review should provide an overview of the existing research on the issue. Body paragraphs should not just summarize each source but analyze them. You can organize your paragraphs with these 3 elements:

• Claim . Start with a topic sentence linked to your literature review purpose.
• Evidence . Cite relevant information from your chosen sources.
• Discussion . Explain how the cited data supports your claim.

Here’s a literature review body paragraph example:

Scholars have examined the link between the aggressor and the victim. Beran et al. (2007) state that students bullied online often become cyberbullies themselves. Faucher et al. (2014) confirm this with their findings: they discovered that male and female students began engaging in cyberbullying after being subject to bullying. Hence, one can conclude that being a victim of bullying increases one’s likelihood of becoming a cyberbully.

Review of Related Literature: Conclusion

A conclusion presents a general consensus on the topic. Depending on your literature review purpose, it might include the following:

• Introduction to further research . If you write a literature review as part of a larger research project, you can present your research question in your conclusion .
• Overview of theories . You can summarize critical theories and concepts to help your reader understand the topic better.
• Discussion of the gap . If you identified a research gap in the reviewed literature, your conclusion could explain why that gap is significant.

Check out a conclusion example that discusses a research gap:

There is extensive research into bullies’ motivation, the consequences of bullying for victims and aggressors, strategies for bullying, and coping with it. Yet, scholars still have not reached a consensus on what to consider the best practices to combat cyberbullying. This question is of great importance because of the significant adverse effects of cyberbullying on victims and bullies.

📋 Format of RRL — APA, MLA, & Others

In this section, we will discuss how to format an RRL according to the most common citation styles: APA, Chicago, MLA, and Harvard.

Writing a literature review using the APA7 style requires the following text formatting:

• When using APA in-text citations , include the author’s last name and the year of publication in parentheses.
• For direct quotations , you must also add the page number. If you use sources without page numbers, such as websites or e-books, include a paragraph number instead.
• When referring to the author’s name in a sentence , you do not need to repeat it at the end of the sentence. Instead, include the year of publication inside the parentheses after their name.
• The reference list should be included at the end of your literature review. It is always alphabetized by the last name of the author (from A to Z), and the lines are indented one-half inch from the left margin of your paper. Do not forget to invert authors’ names (the last name should come first) and include the full titles of journals instead of their abbreviations. If you use an online source, add its URL.

The RRL format in the Chicago style is as follows:

• Author-date . You place your citations in brackets within the text, indicating the name of the author and the year of publication.
• Notes and bibliography . You place your citations in numbered footnotes or endnotes to connect the citation back to the source in the bibliography.
• The reference list, or bibliography , in Chicago style, is at the end of a literature review. The sources are arranged alphabetically and single-spaced. Each bibliography entry begins with the author’s name and the source’s title, followed by publication information, such as the city of publication, the publisher, and the year of publication.

Writing a literature review using the MLA style requires the following text formatting:

• In the MLA format, you can cite a source in the text by indicating the author’s last name and the page number in parentheses at the end of the citation. If the cited information takes several pages, you need to include all the page numbers.
• The reference list in MLA style is titled “ Works Cited .” In this section, all sources used in the paper should be listed in alphabetical order. Each entry should contain the author, title of the source, title of the journal or a larger volume, other contributors, version, number, publisher, and publication date.

The Harvard style requires you to use the following text formatting for your RRL:

• In-text citations in the Harvard style include the author’s last name and the year of publication. If you are using a direct quote in your literature review, you need to add the page number as well.
• Arrange your list of references alphabetically. Each entry should contain the author’s last name, their initials, the year of publication, the title of the source, and other publication information, like the journal title and issue number or the publisher.

✍️ How to Write Review of Related Literature – Sample

Literature reviews can be organized in many ways depending on what you want to achieve with them. In this section, we will look at 3 examples of how you can write your RRL.

Thematic Literature Review

A thematic literature review is arranged around central themes or issues discussed in the sources. If you have identified some recurring themes in the literature, you can divide your RRL into sections that address various aspects of the topic. For example, if you examine studies on e-learning, you can distinguish such themes as the cost-effectiveness of online learning, the technologies used, and its effectiveness compared to traditional education.

Chronological Literature Review

A chronological literature review is a way to track the development of the topic over time. If you use this method, avoid merely listing and summarizing sources in chronological order. Instead, try to analyze the trends, turning moments, and critical debates that have shaped the field’s path. Also, you can give your interpretation of how and why specific advances occurred.

Methodological Literature Review

A methodological literature review differs from the preceding ones in that it usually doesn’t focus on the sources’ content. Instead, it is concerned with the research methods . So, if your references come from several disciplines or fields employing various research techniques, you can compare the findings and conclusions of different methodologies, for instance:

• empirical vs. theoretical studies;
• qualitative vs. quantitative research.

📚 Examples of Review of Related Literature and Studies

We have prepared a short example of RRL on climate change for you to see how everything works in practice!

Climate change is one of the most important issues nowadays. Based on a variety of facts, it is now clearer than ever that humans are altering the Earth's climate. The atmosphere and oceans have warmed, causing sea level rise, a significant loss of Arctic ice, and other climate-related changes. This literature review provides a thorough summary of research on climate change, focusing on climate change fingerprints and evidence of human influence on the Earth's climate system.

Physical Mechanisms and Evidence of Human Influence

Scientists are convinced that climate change is directly influenced by the emission of greenhouse gases. They have carefully analyzed various climate data and evidence, concluding that the majority of the observed global warming over the past 50 years cannot be explained by natural factors alone. Instead, there is compelling evidence pointing to a significant contribution of human activities, primarily the emission of greenhouse gases (Walker, 2014). For example, based on simple physics calculations, doubled carbon dioxide concentration in the atmosphere can lead to a global temperature increase of approximately 1 degree Celsius. (Elderfield, 2022). In order to determine the human influence on climate, scientists still have to analyze a lot of natural changes that affect temperature, precipitation, and other components of climate on timeframes ranging from days to decades and beyond.

Fingerprinting Climate Change

Fingerprinting climate change is a useful tool to identify the causes of global warming because different factors leave unique marks on climate records. This is evident when scientists look beyond overall temperature changes and examine how warming is distributed geographically and over time (Watson, 2022). By investigating these climate patterns, scientists can obtain a more complex understanding of the connections between natural climate variability and climate variability caused by human activity.

Modeling Climate Change and Feedback

To accurately predict the consequences of feedback mechanisms, the rate of warming, and regional climate change, scientists can employ sophisticated mathematical models of the atmosphere, ocean, land, and ice (the cryosphere). These models are grounded in well-established physical laws and incorporate the latest scientific understanding of climate-related processes (Shuckburgh, 2013). Although different climate models produce slightly varying projections for future warming, they all will agree that feedback mechanisms play a significant role in amplifying the initial warming caused by greenhouse gas emissions. (Meehl, 2019).

In conclusion, the literature on global warming indicates that there are well-understood physical processes that link variations in greenhouse gas concentrations to climate change. In addition, it covers the scientific proof that the rates of these gases in the atmosphere have increased and continue to rise fast. According to the sources, the majority of this recent change is almost definitely caused by greenhouse gas emissions produced by human activities. Citizens and governments can alter their energy production methods and consumption patterns to reduce greenhouse gas emissions and, thus, the magnitude of climate change. By acting now, society can prevent the worst consequences of climate change and build a more resilient and sustainable future for generations to come.

Have you ever struggled with finding the topic for an RRL in different subjects? Read the following paragraphs to get some ideas!

Nursing Literature Review Example

Many topics in the nursing field require research. For example, you can write a review of literature related to dengue fever . Give a general overview of dengue virus infections, including its clinical symptoms, diagnosis, prevention, and therapy.

Another good idea is to review related literature and studies about teenage pregnancy . This review can describe the effectiveness of specific programs for adolescent mothers and their children and summarize recommendations for preventing early pregnancy.

📝 Check out some more valuable examples below:

• Hospital Readmissions: Literature Review .
• Literature Review: Lower Sepsis Mortality Rates .
• Breast Cancer: Literature Review .
• Sexually Transmitted Diseases: Literature Review .
• PICO for Pressure Ulcers: Literature Review .
• COVID-19 Spread Prevention: Literature Review .
• Chronic Obstructive Pulmonary Disease: Literature Review .
• Hypertension Treatment Adherence: Literature Review .
• Neonatal Sepsis Prevention: Literature Review .
• Healthcare-Associated Infections: Literature Review .
• Understaffing in Nursing: Literature Review .

Psychology Literature Review Example

If you look for an RRL topic in psychology , you can write a review of related literature about stress . Summarize scientific evidence about stress stages, side effects, types, or reduction strategies. Or you can write a review of related literature about computer game addiction . In this case, you may concentrate on the neural mechanisms underlying the internet gaming disorder, compare it to other addictions, or evaluate treatment strategies.

A review of related literature about cyberbullying is another interesting option. You can highlight the impact of cyberbullying on undergraduate students’ academic, social, and emotional development.

📝 Look at the examples that we have prepared for you to come up with some more ideas:

• Mindfulness in Counseling: A Literature Review .
• Team-Building Across Cultures: Literature Review .
• Anxiety and Decision Making: Literature Review .
• Literature Review on Depression .
• Literature Review on Narcissism .
• Effects of Depression Among Adolescents .
• Causes and Effects of Anxiety in Children .

Literature Review — Sociology Example

Sociological research poses critical questions about social structures and phenomena. For example, you can write a review of related literature about child labor , exploring cultural beliefs and social norms that normalize the exploitation of children. Or you can create a review of related literature about social media . It can investigate the impact of social media on relationships between adolescents or the role of social networks on immigrants’ acculturation .

📝 You can find some more ideas below!

• Single Mothers’ Experiences of Relationships with Their Adolescent Sons .
• Teachers and Students’ Gender-Based Interactions .
• Gender Identity: Biological Perspective and Social Cognitive Theory .
• Gender: Culturally-Prescribed Role or Biological Sex .
• The Influence of Opioid Misuse on Academic Achievement of Veteran Students .
• The Importance of Ethics in Research .
• The Role of Family and Social Network Support in Mental Health .

Education Literature Review Example

For your education studies , you can write a review of related literature about academic performance to determine factors that affect student achievement and highlight research gaps. One more idea is to create a review of related literature on study habits , considering their role in the student’s life and academic outcomes.

You can also evaluate a computerized grading system in a review of related literature to single out its advantages and barriers to implementation. Or you can complete a review of related literature on instructional materials to identify their most common types and effects on student achievement.

📝 Find some inspiration in the examples below:

• Literature Review on Online Learning Challenges From COVID-19 .
• Education, Leadership, and Management: Literature Review .
• Literature Review: Standardized Testing Bias .
• Bullying of Disabled Children in School .
• Interventions and Letter & Sound Recognition: A Literature Review .
• Social-Emotional Skills Program for Preschoolers .
• Effectiveness of Educational Leadership Management Skills .

Business Research Literature Review

If you’re a business student, you can focus on customer satisfaction in your review of related literature. Discuss specific customer satisfaction features and how it is affected by service quality and prices. You can also create a theoretical literature review about consumer buying behavior to evaluate theories that have significantly contributed to understanding how consumers make purchasing decisions.

📝 Look at the examples to get more exciting ideas:

• Leadership and Communication: Literature Review .
• Human Resource Development: Literature Review .
• Project Management. Literature Review .
• Strategic HRM: A Literature Review .
• Customer Relationship Management: Literature Review .
• Literature Review on International Financial Reporting Standards .
• Cultures of Management: Literature Review .

To conclude, a review of related literature is a significant genre of scholarly works that can be applied in various disciplines and for multiple goals. The sources examined in an RRL provide theoretical frameworks for future studies and help create original research questions and hypotheses.

When you finish your outstanding literature review, don’t forget to check whether it sounds logical and coherent. Our text-to-speech tool can help you with that!

• Literature Reviews | University of North Carolina at Chapel Hill
• Writing a Literature Review | Purdue Online Writing Lab
• Learn How to Write a Review of Literature | University of Wisconsin-Madison
• The Literature Review: A Few Tips on Conducting It | University of Toronto
• Writing a Literature Review | UC San Diego
• Conduct a Literature Review | The University of Arizona
• Methods for Literature Reviews | National Library of Medicine
• Literature Reviews: 5. Write the Review | Georgia State University

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How to Write Review of Related Literature (RRL) in Research

A review of related literature (a.k.a RRL in research) is a comprehensive review of the existing literature pertaining to a specific topic or research question. An effective review provides the reader with an organized analysis and synthesis of the existing knowledge about a subject. With the increasing amount of new information being disseminated every day, conducting a review of related literature is becoming more difficult and the purpose of review of related literature is clearer than ever.  

All new knowledge is necessarily based on previously known information, and every new scientific study must be conducted and reported in the context of previous studies. This makes a review of related literature essential for research, and although it may be tedious work at times , most researchers will complete many such reviews of varying depths during their career. So, why exactly is a review of related literature important?    

Table of Contents

Why a review of related literature in research is important  

Before thinking how to do reviews of related literature , it is necessary to understand its importance. Although the purpose of a review of related literature varies depending on the discipline and how it will be used, its importance is never in question. Here are some ways in which a review can be crucial.  

• Identify gaps in the knowledge – This is the primary purpose of a review of related literature (often called RRL in research ). To create new knowledge, you must first determine what knowledge may be missing. This also helps to identify the scope of your study.  
• Avoid duplication of research efforts – Not only will a review of related literature indicate gaps in the existing research, but it will also lead you away from duplicating research that has already been done and thus save precious resources.  
• Provide an overview of disparate and interdisciplinary research areas – Researchers cannot possibly know everything related to their disciplines. Therefore, it is very helpful to have access to a review of related literature already written and published.  
• Highlight researcher’s familiarity with their topic 1  – A strong review of related literature in a study strengthens readers’ confidence in that study and that researcher.

Tips on how to write a review of related literature in research

Given that you will probably need to produce a number of these at some point, here are a few general tips on how to write an effective review of related literature 2 .

• Define your topic, audience, and purpose: You will be spending a lot of time with this review, so choose a topic that is interesting to you. While deciding what to write in a review of related literature , think about who you expect to read the review – researchers in your discipline, other scientists, the general public – and tailor the language to the audience. Also, think about the purpose of your review of related literature .  
• Conduct a comprehensive literature search: While writing your review of related literature , emphasize more recent works but don’t forget to include some older publications as well. Cast a wide net, as you may find some interesting and relevant literature in unexpected databases or library corners. Don’t forget to search for recent conference papers.
• Review the identified articles and take notes: It is a good idea to take notes in a way such that individual items in your notes can be moved around when you organize them. For example, index cards are great tools for this. Write each individual idea on a separate card along with the source. The cards can then be easily grouped and organized.  
• Determine how to organize your review: A review of related literature should not be merely a listing of descriptions. It should be organized by some criterion, such as chronologically or thematically.  
• Be critical and objective: Don’t just report the findings of other studies in your review of related literature . Challenge the methodology, find errors in the analysis, question the conclusions. Use what you find to improve your research. However, do not insert your opinions into the review of related literature. Remain objective and open-minded.  
• Structure your review logically: Guide the reader through the information. The structure will depend on the function of the review of related literature. Creating an outline prior to writing the RRL in research is a good way to ensure the presented information flows well.  

As you read more extensively in your discipline, you will notice that the review of related literature appears in various forms in different places. For example, when you read an article about an experimental study, you will typically see a literature review or a RRL in research , in the introduction that includes brief descriptions of similar studies. In longer research studies and dissertations, especially in the social sciences, the review of related literature will typically be a separate chapter and include more information on methodologies and theory building. In addition, stand-alone review articles will be published that are extremely useful to researchers.  

The review of relevant literature or often abbreviated as, RRL in research , is an important communication tool that can be used in many forms for many purposes. It is a tool that all researchers should befriend.  

• University of North Carolina at Chapel Hill Writing Center. Literature Reviews.  https://writingcenter.unc.edu/tips-and-tools/literature-reviews/  [Accessed September 8, 2022]
• Pautasso M. Ten simple rules for writing a literature review. PLoS Comput Biol. 2013, 9. doi: 10.1371/journal.pcbi.1003149.

Q:  Is research complete without a review of related literature?

A research project is usually considered incomplete without a proper review of related literature. The review of related literature is a crucial component of any research project as it provides context for the research question, identifies gaps in existing literature, and ensures novelty by avoiding duplication. It also helps inform research design and supports arguments, highlights the significance of a study, and demonstrates your knowledge an expertise.

Q: What is difference between RRL and RRS?

The key difference between an RRL and an RRS lies in their focus and scope. An RRL or review of related literature examines a broad range of literature, including theoretical frameworks, concepts, and empirical studies, to establish the context and significance of the research topic. On the other hand, an RRS or review of research studies specifically focuses on analyzing and summarizing previous research studies within a specific research domain to gain insights into methodologies, findings, and gaps in the existing body of knowledge. While there may be some overlap between the two, they serve distinct purposes and cover different aspects of the research process.

Q: Does review of related literature improve accuracy and validity of research?

Yes, a comprehensive review of related literature (RRL) plays a vital role in improving the accuracy and validity of research. It helps authors gain a deeper understanding and offers different perspectives on the research topic. RRL can help you identify research gaps, dictate the selection of appropriate research methodologies, enhance theoretical frameworks, avoid biases and errors, and even provide support for research design and interpretation. By building upon and critically engaging with existing related literature, researchers can ensure their work is rigorous, reliable, and contributes meaningfully to their field of study.

R Discovery is a literature search and research reading platform that accelerates your research discovery journey by keeping you updated on the latest, most relevant scholarly content. With 250M+ research articles sourced from trusted aggregators like CrossRef, Unpaywall, PubMed, PubMed Central, Open Alex and top publishing houses like Springer Nature, JAMA, IOP, Taylor & Francis, NEJM, BMJ, Karger, SAGE, Emerald Publishing and more, R Discovery puts a world of research at your fingertips.  

Try R Discovery Prime FREE for 1 week or upgrade at just US$72 a year to access premium features that let you listen to research on the go, read in your language, collaborate with peers, auto sync with reference managers, and much more. Choose a simpler, smarter way to find and read research – Download the app and start your free 7-day trial today !  

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How to Make a Literature Review in Research (RRL Example)

What is an RRL in a research paper?

A relevant review of the literature (RRL) is an objective, concise, critical summary of published research literature relevant to a topic being researched in an article. In an RRL, you discuss knowledge and findings from existing literature relevant to your study topic. If there are conflicts or gaps in existing literature, you can also discuss these in your review, as well as how you will confront these missing elements or resolve these issues in your study.

To complete an RRL, you first need to collect relevant literature; this can include online and offline sources. Save all of your applicable resources as you will need to include them in your paper. When looking through these sources, take notes and identify concepts of each source to describe in the review of the literature.

A good RRL does NOT:

A literature review does not simply reference and list all of the material you have cited in your paper.

• Presenting material that is not directly relevant to your study will distract and frustrate the reader and make them lose sight of the purpose of your study.
• Starting a literature review with “A number of scholars have studied the relationship between X and Y” and simply listing who has studied the topic and what each scholar concluded is not going to strengthen your paper.

A good RRL DOES:

• Present a brief typology that orders articles and books into groups to help readers focus on unresolved debates, inconsistencies, tensions, and new questions about a research topic.
• Summarize the most relevant and important aspects of the scientific literature related to your area of research
• Synthesize what has been done in this area of research and by whom, highlight what previous research indicates about a topic, and identify potential gaps and areas of disagreement in the field
• Give the reader an understanding of the background of the field and show which studies are important—and highlight errors in previous studies

How long is a review of the literature for a research paper?

The length of a review of the literature depends on its purpose and target readership and can vary significantly in scope and depth. In a dissertation, thesis, or standalone review of literature, it is usually a full chapter of the text (at least 20 pages). Whereas, a standard research article or school assignment literature review section could only be a few paragraphs in the Introduction section .

Building Your Literature Review Bookshelf

One way to conceive of a literature review is to think about writing it as you would build a bookshelf. You don’t need to cut each piece by yourself from scratch. Rather, you can take the pieces that other researchers have cut out and put them together to build a framework on which to hang your own “books”—that is, your own study methods, results, and conclusions.

What Makes a Good Literature Review?

The contents of a literature review (RRL) are determined by many factors, including its precise purpose in the article, the degree of consensus with a given theory or tension between competing theories, the length of the article, the number of previous studies existing in the given field, etc. The following are some of the most important elements that a literature review provides.

Historical background for your research

Analyze what has been written about your field of research to highlight what is new and significant in your study—or how the analysis itself contributes to the understanding of this field, even in a small way. Providing a historical background also demonstrates to other researchers and journal editors your competency in discussing theoretical concepts. You should also make sure to understand how to paraphrase scientific literature to avoid plagiarism in your work.

The current context of your research

Discuss central (or peripheral) questions, issues, and debates in the field. Because a field is constantly being updated by new work, you can show where your research fits into this context and explain developments and trends in research.

A discussion of relevant theories and concepts

Theories and concepts should provide the foundation for your research. For example, if you are researching the relationship between ecological environments and human populations, provide models and theories that focus on specific aspects of this connection to contextualize your study. If your study asks a question concerning sustainability, mention a theory or model that underpins this concept. If it concerns invasive species, choose material that is focused in this direction.

Definitions of relevant terminology

In the natural sciences, the meaning of terms is relatively straightforward and consistent. But if you present a term that is obscure or context-specific, you should define the meaning of the term in the Introduction section (if you are introducing a study) or in the summary of the literature being reviewed.

Description of related relevant research

Include a description of related research that shows how your work expands or challenges earlier studies or fills in gaps in previous work. You can use your literature review as evidence of what works, what doesn’t, and what is missing in the field.

Supporting evidence for a practical problem or issue your research is addressing that demonstrates its importance: Referencing related research establishes your area of research as reputable and shows you are building upon previous work that other researchers have deemed significant.

Types of Literature Reviews

Literature reviews can differ in structure, length, amount, and breadth of content included. They can range from selective (a very narrow area of research or only a single work) to comprehensive (a larger amount or range of works). They can also be part of a larger work or stand on their own.

• A course assignment is an example of a selective, stand-alone work. It focuses on a small segment of the literature on a topic and makes up an entire work on its own.
• The literature review in a dissertation or thesis is both comprehensive and helps make up a larger work.
• A majority of journal articles start with a selective literature review to provide context for the research reported in the study; such a literature review is usually included in the Introduction section (but it can also follow the presentation of the results in the Discussion section ).
• Some literature reviews are both comprehensive and stand as a separate work—in this case, the entire article analyzes the literature on a given topic.

Literature Reviews Found in Academic Journals

The two types of literature reviews commonly found in journals are those introducing research articles (studies and surveys) and stand-alone literature analyses. They can differ in their scope, length, and specific purpose.

Literature reviews introducing research articles

The literature review found at the beginning of a journal article is used to introduce research related to the specific study and is found in the Introduction section, usually near the end. It is shorter than a stand-alone review because it must be limited to very specific studies and theories that are directly relevant to the current study. Its purpose is to set research precedence and provide support for the study’s theory, methods, results, and/or conclusions. Not all research articles contain an explicit review of the literature, but most do, whether it is a discrete section or indistinguishable from the rest of the Introduction.

How to structure a literature review for an article

When writing a literature review as part of an introduction to a study, simply follow the structure of the Introduction and move from the general to the specific—presenting the broadest background information about a topic first and then moving to specific studies that support your rationale , finally leading to your hypothesis statement. Such a literature review is often indistinguishable from the Introduction itself—the literature is INTRODUCING the background and defining the gaps your study aims to fill.

The stand-alone literature review

The literature review published as a stand-alone article presents and analyzes as many of the important publications in an area of study as possible to provide background information and context for a current area of research or a study. Stand-alone reviews are an excellent resource for researchers when they are first searching for the most relevant information on an area of study.

Such literature reviews are generally a bit broader in scope and can extend further back in time. This means that sometimes a scientific literature review can be highly theoretical, in addition to focusing on specific methods and outcomes of previous studies. In addition, all sections of such a “review article” refer to existing literature rather than describing the results of the authors’ own study.

In addition, this type of literature review is usually much longer than the literature review introducing a study. At the end of the review follows a conclusion that once again explicitly ties all of the cited works together to show how this analysis is itself a contribution to the literature. While not absolutely necessary, such articles often include the terms “Literature Review” or “Review of the Literature” in the title. Whether or not that is necessary or appropriate can also depend on the specific author instructions of the target journal. Have a look at this article for more input on how to compile a stand-alone review article that is insightful and helpful for other researchers in your field.

How to Write a Literature Review in 6 Steps

So how do authors turn a network of articles into a coherent review of relevant literature?

Writing a literature review is not usually a linear process—authors often go back and check the literature while reformulating their ideas or making adjustments to their study. Sometimes new findings are published before a study is completed and need to be incorporated into the current work. This also means you will not be writing the literature review at any one time, but constantly working on it before, during, and after your study is complete.

Here are some steps that will help you begin and follow through on your literature review.

Step 1: Choose a topic to write about—focus on and explore this topic.

Choose a topic that you are familiar with and highly interested in analyzing; a topic your intended readers and researchers will find interesting and useful; and a topic that is current, well-established in the field, and about which there has been sufficient research conducted for a review. This will help you find the “sweet spot” for what to focus on.

Step 2: Research and collect all the scholarly information on the topic that might be pertinent to your study.

This includes scholarly articles, books, conventions, conferences, dissertations, and theses—these and any other academic work related to your area of study is called “the literature.”

Step 3: Analyze the network of information that extends or responds to the major works in your area; select the material that is most useful.

Use thought maps and charts to identify intersections in the research and to outline important categories; select the material that will be most useful to your review.

Step 4: Describe and summarize each article—provide the essential information of the article that pertains to your study.

Determine 2-3 important concepts (depending on the length of your article) that are discussed in the literature; take notes about all of the important aspects of this study relevant to the topic being reviewed.

For example, in a given study, perhaps some of the main concepts are X, Y, and Z. Note these concepts and then write a brief summary about how the article incorporates them. In reviews that introduce a study, these can be relatively short. In stand-alone reviews, there may be significantly more texts and more concepts.

Step 5: Demonstrate how these concepts in the literature relate to what you discovered in your study or how the literature connects the concepts or topics being discussed.

In a literature review intro for an article, this information might include a summary of the results or methods of previous studies that correspond to and/or confirm those sections in your own study. For a stand-alone literature review, this may mean highlighting the concepts in each article and showing how they strengthen a hypothesis or show a pattern.

Discuss unaddressed issues in previous studies. These studies that are missing something you address are important to include in your literature review. In addition, those works whose theories and conclusions directly support your findings will be valuable to review here.

Step 6: Identify relationships in the literature and develop and connect your own ideas to them.

This is essentially the same as step 5 but focused on the connections between the literature and the current study or guiding concepts or arguments of the paper, not only on the connections between the works themselves.

Your hypothesis, argument, or guiding concept is the “golden thread” that will ultimately tie the works together and provide readers with specific insights they didn’t have before reading your literature review. Make sure you know where to put the research question , hypothesis, or statement of the problem in your research paper so that you guide your readers logically and naturally from your introduction of earlier work and evidence to the conclusions you want them to draw from the bigger picture.

Your literature review will not only cover publications on your topics but will include your own ideas and contributions. By following these steps you will be telling the specific story that sets the background and shows the significance of your research and you can turn a network of related works into a focused review of the literature.

Literature Review (RRL) Examples

Because creating sample literature reviews would take too long and not properly capture the nuances and detailed information needed for a good review, we have included some links to different types of literature reviews below. You can find links to more literature reviews in these categories by visiting the TUS Library’s website . Sample literature reviews as part of an article, dissertation, or thesis:

• Critical Thinking and Transferability: A Review of the Literature (Gwendolyn Reece)
• Building Customer Loyalty: A Customer Experience Based Approach in a Tourism Context (Martina Donnelly)

Sample stand-alone literature reviews

• Literature Review on Attitudes towards Disability (National Disability Authority)
• The Effects of Communication Styles on Marital Satisfaction (Hannah Yager)

Additional Literature Review Format Guidelines

In addition to the content guidelines above, authors also need to check which style guidelines to use ( APA , Chicago, MLA, etc.) and what specific rules the target journal might have for how to structure such articles or how many studies to include—such information can usually be found on the journals’ “Guide for Authors” pages. Additionally, use one of the four Wordvice citation generators below, choosing the citation style needed for your paper:

Wordvice Writing and Academic Editing Resources

Finally, after you have finished drafting your literature review, be sure to receive professional proofreading services , including paper editing for your academic work. A competent proofreader who understands academic writing conventions and the specific style guides used by academic journals will ensure that your paper is ready for publication in your target journal.

See our academic resources for further advice on references in your paper , how to write an abstract , how to write a research paper title, how to impress the editor of your target journal with a perfect cover letter , and dozens of other research writing and publication topics.

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• 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.

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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.

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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 .

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Writing Research Papers

• Writing a Literature Review

When writing a research paper on a specific topic, you will often need to include an overview of any prior research that has been conducted on that topic.  For example, if your research paper is describing an experiment on fear conditioning, then you will probably need to provide an overview of prior research on fear conditioning.  That overview is typically known as a literature review.  

Please note that a full-length literature review article may be suitable for fulfilling the requirements for the Psychology B.S. Degree Research Paper .  For further details, please check with your faculty advisor.

Different Types of Literature Reviews

Literature reviews come in many forms.  They can be part of a research paper, for example as part of the Introduction section.  They can be one chapter of a doctoral dissertation.  Literature reviews can also “stand alone” as separate articles by themselves.  For instance, some journals such as Annual Review of Psychology , Psychological Bulletin , and others typically publish full-length review articles.  Similarly, in courses at UCSD, you may be asked to write a research paper that is itself a literature review (such as, with an instructor’s permission, in fulfillment of the B.S. Degree Research Paper requirement). Alternatively, you may be expected to include a literature review as part of a larger research paper (such as part of an Honors Thesis). 

Literature reviews can be written using a variety of different styles.  These may differ in the way prior research is reviewed as well as the way in which the literature review is organized.  Examples of stylistic variations in literature reviews include: 

• Summarization of prior work vs. critical evaluation. In some cases, prior research is simply described and summarized; in other cases, the writer compares, contrasts, and may even critique prior research (for example, discusses their strengths and weaknesses).
• Chronological vs. categorical and other types of organization. In some cases, the literature review begins with the oldest research and advances until it concludes with the latest research.  In other cases, research is discussed by category (such as in groupings of closely related studies) without regard for chronological order.  In yet other cases, research is discussed in terms of opposing views (such as when different research studies or researchers disagree with one another).

Overall, all literature reviews, whether they are written as a part of a larger work or as separate articles unto themselves, have a common feature: they do not present new research; rather, they provide an overview of prior research on a specific topic . 

How to Write a Literature Review

When writing a literature review, it can be helpful to rely on the following steps.  Please note that these procedures are not necessarily only for writing a literature review that becomes part of a larger article; they can also be used for writing a full-length article that is itself a literature review (although such reviews are typically more detailed and exhaustive; for more information please refer to the Further Resources section of this page).

Steps for Writing a Literature Review

1. Identify and define the topic that you will be reviewing.

The topic, which is commonly a research question (or problem) of some kind, needs to be identified and defined as clearly as possible.  You need to have an idea of what you will be reviewing in order to effectively search for references and to write a coherent summary of the research on it.  At this stage it can be helpful to write down a description of the research question, area, or topic that you will be reviewing, as well as to identify any keywords that you will be using to search for relevant research.

2. Conduct a literature search.

Use a range of keywords to search databases such as PsycINFO and any others that may contain relevant articles.  You should focus on peer-reviewed, scholarly articles.  Published books may also be helpful, but keep in mind that peer-reviewed articles are widely considered to be the “gold standard” of scientific research.  Read through titles and abstracts, select and obtain articles (that is, download, copy, or print them out), and save your searches as needed.  For more information about this step, please see the Using Databases and Finding Scholarly References section of this website.

3. Read through the research that you have found and take notes.

Absorb as much information as you can.  Read through the articles and books that you have found, and as you do, take notes.  The notes should include anything that will be helpful in advancing your own thinking about the topic and in helping you write the literature review (such as key points, ideas, or even page numbers that index key information).  Some references may turn out to be more helpful than others; you may notice patterns or striking contrasts between different sources ; and some sources may refer to yet other sources of potential interest.  This is often the most time-consuming part of the review process.  However, it is also where you get to learn about the topic in great detail.  For more details about taking notes, please see the “Reading Sources and Taking Notes” section of the Finding Scholarly References page of this website.

4. Organize your notes and thoughts; create an outline.

At this stage, you are close to writing the review itself.  However, it is often helpful to first reflect on all the reading that you have done.  What patterns stand out?  Do the different sources converge on a consensus?  Or not?  What unresolved questions still remain?  You should look over your notes (it may also be helpful to reorganize them), and as you do, to think about how you will present this research in your literature review.  Are you going to summarize or critically evaluate?  Are you going to use a chronological or other type of organizational structure?  It can also be helpful to create an outline of how your literature review will be structured.

5. Write the literature review itself and edit and revise as needed.

The final stage involves writing.  When writing, keep in mind that literature reviews are generally characterized by a summary style in which prior research is described sufficiently to explain critical findings but does not include a high level of detail (if readers want to learn about all the specific details of a study, then they can look up the references that you cite and read the original articles themselves).  However, the degree of emphasis that is given to individual studies may vary (more or less detail may be warranted depending on how critical or unique a given study was).   After you have written a first draft, you should read it carefully and then edit and revise as needed.  You may need to repeat this process more than once.  It may be helpful to have another person read through your draft(s) and provide feedback.

6. Incorporate the literature review into your research paper draft.

After the literature review is complete, you should incorporate it into your research paper (if you are writing the review as one component of a larger paper).  Depending on the stage at which your paper is at, this may involve merging your literature review into a partially complete Introduction section, writing the rest of the paper around the literature review, or other processes.

Further Tips for Writing a Literature Review

Full-length literature reviews

• Many full-length literature review articles use a three-part structure: Introduction (where the topic is identified and any trends or major problems in the literature are introduced), Body (where the studies that comprise the literature on that topic are discussed), and Discussion or Conclusion (where major patterns and points are discussed and the general state of what is known about the topic is summarized)

Literature reviews as part of a larger paper

• An “express method” of writing a literature review for a research paper is as follows: first, write a one paragraph description of each article that you read. Second, choose how you will order all the paragraphs and combine them in one document.  Third, add transitions between the paragraphs, as well as an introductory and concluding paragraph. 1
• A literature review that is part of a larger research paper typically does not have to be exhaustive. Rather, it should contain most or all of the significant studies about a research topic but not tangential or loosely related ones. 2   Generally, literature reviews should be sufficient for the reader to understand the major issues and key findings about a research topic.  You may however need to confer with your instructor or editor to determine how comprehensive you need to be.

Benefits of Literature Reviews

By summarizing prior research on a topic, literature reviews have multiple benefits.  These include:

• Literature reviews help readers understand what is known about a topic without having to find and read through multiple sources.
• Literature reviews help “set the stage” for later reading about new research on a given topic (such as if they are placed in the Introduction of a larger research paper). In other words, they provide helpful background and context.
• Literature reviews can also help the writer learn about a given topic while in the process of preparing the review itself. In the act of research and writing the literature review, the writer gains expertise on the topic .

Downloadable Resources

• How to Write APA Style Research Papers (a comprehensive guide) [ PDF ]
• Tips for Writing APA Style Research Papers (a brief summary) [ PDF ]
• Example APA Style Research Paper (for B.S. Degree – literature review) [ PDF ]

Further Resources

How-To Videos     

• Writing Research Paper Videos
• UCSD Library Psychology Research Guide: Literature Reviews

External Resources

• Developing and Writing a Literature Review from N Carolina A&T State University
• Example of a Short Literature Review from York College CUNY
• How to Write a Review of Literature from UW-Madison
• Writing a Literature Review from UC Santa Cruz  
• Pautasso, M. (2013). Ten Simple Rules for Writing a Literature Review. PLoS Computational Biology, 9 (7), e1003149. doi : 1371/journal.pcbi.1003149

1 Ashton, W. Writing a short literature review . [PDF]     

2 carver, l. (2014).  writing the research paper [workshop]. , prepared by s. c. pan for ucsd psychology.

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Literature Review

What is a Literature Review?

It is…. a systematic and critical analysis of the literature on a specific topic. It describes trends, quality, relationships, inconsistencies and gaps in the research; and it details how the works enhance your understanding of the topic at large.

It is NOT…. simply an annotated bibliography that summarizes and/or assesses each article. There is not one, correct way to approach and write a literature review. It can be a stand-alone paper or part of a thesis/dissertation. Format and requirements can vary between disciplines, purpose and intended audience.

A literature review is an overview of existing literature (books, articles, dissertations, conference proceedings, and other sources) in a particular scholarly area. With a lit review, you will:

• Gather information about your topic, including the sources used by others who have previously conducted research
• Find out if your specific research question has already been answered
• Find out what areas or perspectives have not yet been covered by others on your topic
• Analyze and evaluate existing information

The literature review will assist you in considering the validity and scope of your research question so that you can do the necessary revision and fine tuning to it. It provides the foundation to formulate and present strong arguments to justify your chosen research topic.

• How to Write a Literature Review  (University of California, Santa Cruz)

Check out these books from the library for further guidance:

• Després, Carole. "The meaning of home: literature review and directions for future research and theoretical development." Journal of architectural and planning research 8, no.2, (Summer 1991): 96-155.
• Steiner, Frederick R. "Philadelphia, the holy experiment: A literature review and analysis." Ekistics , 49, (1982): 298-305.

Reckoning with Authorities

As you are developing your Lit Review, part of your objective is to identify the leading authorities within the field or who address your topic or theme. Some tips for identifying the scholars:

Old Fashioned Method:

• Keep notes on footnotes and names as you read articles, books, blogs, exhibition catalogs, etc. Are there names or works that everyone references? Use the catalog to track these reference down.
• Consider looking for state of the field articles often found either in a discipline's primary journal or in conference proceedings - keynote speakers.
• Look for book reviews.

Publication Metrics:

• These resources include information about the frequency of citations for an article/author.
• These resources are not specifically for Architecture or Planning. Remember therefore to be critical and careful about the assumptions you make with regard to the results!

The Web of Science platform currently also provides temporary access to several databases that are not part of the Core Collection, including Biosis Citation Index, Data Citation Index, and Zoological Record.

Use this link to access Google Scholar, and see our Google Scholar Guide for information on using this resource.

If you encounter a warning about the security certificate when using the FindIt@UT tool in Google Scholar, you can learn more about that using this guide .

• Last Updated: Oct 5, 2023 8:40 AM
• URL: https://guides.lib.utexas.edu/architecture

A quick guide to conducting an effective review of related literature (RRL)

Planning to Write

Malvika Gaur

A question that we often get asked is how to review related literature. However, before we discuss that let’s first understand what a review of related literature (RRL) is.

What’s an RRL?

Put simply, RRL is a thorough and in-depth analysis of existing literature related to the topic of your thesis or dissertation. In an RRL, you can include the concepts, methods, and results of the existing literature relevant to your topic; this will give you an overview of what has been done in your field of research, the methods adopted that lead to the conclusions mentioned in the existing literature, and if there is a gap or conflict in the existing literature. The gap or conflict is what you can address through your research question.

Is it worth spending all that time on a detailed literature review?

Yes! A detailed literature review has a three-fold purpose:

1. Enables you to showcase your understanding of the subject and the work done in your field till the time of your research. 

2.  Helps you define the problem statement and the purpose of your own research by identifying and highlighting a gap or conflict in the existing literature.

3. Helps you set context for your research by summarizing everything that your readers—journal editors, referees, and other researchers—must know about your field of research to comprehend your work better.

Easy steps to doing an effective review of related literature

Before you begin the RRL

1. Decide how you wish to organize your review:

There are several approaches you may take to present your literature review. Through this table, you may understand the difference between two of the most used approaches and choose the best approach for your manuscript:

2. Understand the difference between a study background and a literature review: Understand how study background and literature review are different here: INFOGRAPHIC: 6 Differences between study background and literature review

3. Shortlist a good reference management software: It is also recommended that you shortlist a good reference management software like Zotero to manage your bibliographic data and related research materials.

During the literature review process and at the writing stage

1. Identify relevant literature: The first and foremost step to conduct an RRL is to identify relevant literature. You can do this through various sources, online and offline. When going through the resources, make notes and identify key concepts of each resource to describe in the review. Discovering relevant work is highly important. Targeted search, following the citations of any relevant manuscript, and using a reference manager are some of the things to remember. You may look for other useful tips here: Tips for effective literature searching and keeping up with new publications

2. Structure your literature review well as you write it:

Similar to other components of a manuscript like the Introduction and Method sections, literature review is an important part of your manuscript. A literature review, especially if it is a stand-alone paper would usually have these components:

• Introduction:  You may begin your RRL by setting some context for your readers by providing information about the field of study, the relevance of the chosen topic within the field, and the focus of the literature review.
• Methods:  In this section, you may describe the criteria used to select the sources or the way in which the information has been presented. This makes it easier for the readers to understand your approach.
• Body:  This section is where you list all the related literature and talk about their relevance with respect to your research. The structure of the list depends entirely upon the approach you wish to take—chronological or thematic o any other. A chronological model would probably have different paragraphs for different time periods, while a thematic model would have sub-topics based on the different themes.
• Discussion and conclusion:  This section summarizes the main contributions of significant studies and discusses the questions that the review has raised about the topic and field. This is also the section where you highlight the gaps in research that the review has sparked and the possible suggestions for future research.
• Reference list:  The reference list is a very important part of a literature review as your article is based entirely on primary sources. The reference list should be comprehensive and page numbers and section details should be provided wherever necessary.

However, if the literature review is part of the manuscript, then the way it is structured will depend on journal requirements. It can be written as a single paragraph, but the paragraph can be structured to include the Introduction, Methods, etc. but without the actual sub-headings.

While a literature review can be published as an independent piece of writing or as part of a larger article, the basis for any kind of review of literature remains the same. It allows new researchers and busy scientists in the field to keep up to date with the latest happenings in the field and helps them to identify potential areas of research.

If you have any further doubts related to this topic, feel free to use the comments section to ask questions. Alternately, you can also post your question on our Q&A forum and our expert will be sure to provide the necessary guidance.

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A literature review surveys prior research published in books, scholarly articles, and any other sources relevant to a particular issue, area of research, or theory, and by so doing, provides a description, summary, and critical evaluation of these works in relation to the research problem being investigated. Literature reviews are designed to provide an overview of sources you have used in researching a particular topic and to demonstrate to your readers how your research fits within existing scholarship about the topic.

Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper . Fourth edition. Thousand Oaks, CA: SAGE, 2014.

Importance of a Good Literature Review

A literature review may consist of simply a summary of key sources, but in the social sciences, a literature review usually has an organizational pattern and combines both summary and synthesis, often within specific conceptual categories . A summary is a recap of the important information of the source, but a synthesis is a re-organization, or a reshuffling, of that information in a way that informs how you are planning to investigate a research problem. The analytical features of a literature review might:

• Give a new interpretation of old material or combine new with old interpretations,
• Trace the intellectual progression of the field, including major debates,
• Depending on the situation, evaluate the sources and advise the reader on the most pertinent or relevant research, or
• Usually in the conclusion of a literature review, identify where gaps exist in how a problem has been researched to date.

Given this, the purpose of a literature review is to:

• Place each work in the context of its contribution to understanding the research problem being studied.
• Describe the relationship of each work to the others under consideration.
• Identify new ways to interpret prior research.
• Reveal any gaps that exist in the literature.
• Resolve conflicts amongst seemingly contradictory previous studies.
• Identify areas of prior scholarship to prevent duplication of effort.
• Point the way in fulfilling a need for additional research.
• Locate your own research within the context of existing literature [very important].

Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper. 2nd ed. Thousand Oaks, CA: Sage, 2005; Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination . Thousand Oaks, CA: Sage Publications, 1998; Jesson, Jill. Doing Your Literature Review: Traditional and Systematic Techniques . Los Angeles, CA: SAGE, 2011; Knopf, Jeffrey W. "Doing a Literature Review." PS: Political Science and Politics 39 (January 2006): 127-132; Ridley, Diana. The Literature Review: A Step-by-Step Guide for Students . 2nd ed. Los Angeles, CA: SAGE, 2012.

Types of Literature Reviews

It is important to think of knowledge in a given field as consisting of three layers. First, there are the primary studies that researchers conduct and publish. Second are the reviews of those studies that summarize and offer new interpretations built from and often extending beyond the primary studies. Third, there are the perceptions, conclusions, opinion, and interpretations that are shared informally among scholars that become part of the body of epistemological traditions within the field.

In composing a literature review, it is important to note that it is often this third layer of knowledge that is cited as "true" even though it often has only a loose relationship to the primary studies and secondary literature reviews. Given this, while literature reviews are designed to provide an overview and synthesis of pertinent sources you have explored, there are a number of approaches you could adopt depending upon the type of analysis underpinning your study.

Argumentative Review This form examines literature selectively in order to support or refute an argument, deeply embedded assumption, or philosophical problem already established in the literature. The purpose is to develop a body of literature that establishes a contrarian viewpoint. Given the value-laden nature of some social science research [e.g., educational reform; immigration control], argumentative approaches to analyzing the literature can be a legitimate and important form of discourse. However, note that they can also introduce problems of bias when they are used to make summary claims of the sort found in systematic reviews [see below].

Integrative Review Considered a form of research that reviews, critiques, and synthesizes representative literature on a topic in an integrated way such that new frameworks and perspectives on the topic are generated. The body of literature includes all studies that address related or identical hypotheses or research problems. A well-done integrative review meets the same standards as primary research in regard to clarity, rigor, and replication. This is the most common form of review in the social sciences.

Historical Review Few things rest in isolation from historical precedent. Historical literature reviews focus on examining research throughout a period of time, often starting with the first time an issue, concept, theory, phenomena emerged in the literature, then tracing its evolution within the scholarship of a discipline. The purpose is to place research in a historical context to show familiarity with state-of-the-art developments and to identify the likely directions for future research.

Methodological Review A review does not always focus on what someone said [findings], but how they came about saying what they say [method of analysis]. Reviewing methods of analysis provides a framework of understanding at different levels [i.e. those of theory, substantive fields, research approaches, and data collection and analysis techniques], how researchers draw upon a wide variety of knowledge ranging from the conceptual level to practical documents for use in fieldwork in the areas of ontological and epistemological consideration, quantitative and qualitative integration, sampling, interviewing, data collection, and data analysis. This approach helps highlight ethical issues which you should be aware of and consider as you go through your own study.

Systematic Review This form consists of an overview of existing evidence pertinent to a clearly formulated research question, which uses pre-specified and standardized methods to identify and critically appraise relevant research, and to collect, report, and analyze data from the studies that are included in the review. The goal is to deliberately document, critically evaluate, and summarize scientifically all of the research about a clearly defined research problem . Typically it focuses on a very specific empirical question, often posed in a cause-and-effect form, such as "To what extent does A contribute to B?" This type of literature review is primarily applied to examining prior research studies in clinical medicine and allied health fields, but it is increasingly being used in the social sciences.

Theoretical Review The purpose of this form is to examine the corpus of theory that has accumulated in regard to an issue, concept, theory, phenomena. The theoretical literature review helps to establish what theories already exist, the relationships between them, to what degree the existing theories have been investigated, and to develop new hypotheses to be tested. Often this form is used to help establish a lack of appropriate theories or reveal that current theories are inadequate for explaining new or emerging research problems. The unit of analysis can focus on a theoretical concept or a whole theory or framework.

NOTE : Most often the literature review will incorporate some combination of types. For example, a review that examines literature supporting or refuting an argument, assumption, or philosophical problem related to the research problem will also need to include writing supported by sources that establish the history of these arguments in the literature.

Baumeister, Roy F. and Mark R. Leary. "Writing Narrative Literature Reviews."  Review of General Psychology 1 (September 1997): 311-320; Mark R. Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper . 2nd ed. Thousand Oaks, CA: Sage, 2005; Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination . Thousand Oaks, CA: Sage Publications, 1998; Kennedy, Mary M. "Defining a Literature." Educational Researcher 36 (April 2007): 139-147; Petticrew, Mark and Helen Roberts. Systematic Reviews in the Social Sciences: A Practical Guide . Malden, MA: Blackwell Publishers, 2006; Torracro, Richard. "Writing Integrative Literature Reviews: Guidelines and Examples." Human Resource Development Review 4 (September 2005): 356-367; Rocco, Tonette S. and Maria S. Plakhotnik. "Literature Reviews, Conceptual Frameworks, and Theoretical Frameworks: Terms, Functions, and Distinctions." Human Ressource Development Review 8 (March 2008): 120-130; Sutton, Anthea. Systematic Approaches to a Successful Literature Review . Los Angeles, CA: Sage Publications, 2016.

Structure and Writing Style

I.  Thinking About Your Literature Review

The structure of a literature review should include the following in support of understanding the research problem :

• An overview of the subject, issue, or theory under consideration, along with the objectives of the literature review,
• Division of works under review into themes or categories [e.g. works that support a particular position, those against, and those offering alternative approaches entirely],
• An explanation of how each work is similar to and how it varies from the others,
• Conclusions as to which pieces are best considered in their argument, are most convincing of their opinions, and make the greatest contribution to the understanding and development of their area of research.

The critical evaluation of each work should consider :

• Provenance -- what are the author's credentials? Are the author's arguments supported by evidence [e.g. primary historical material, case studies, narratives, statistics, recent scientific findings]?
• Methodology -- were the techniques used to identify, gather, and analyze the data appropriate to addressing the research problem? Was the sample size appropriate? Were the results effectively interpreted and reported?
• Objectivity -- is the author's perspective even-handed or prejudicial? Is contrary data considered or is certain pertinent information ignored to prove the author's point?
• Persuasiveness -- which of the author's theses are most convincing or least convincing?
• Validity -- are the author's arguments and conclusions convincing? Does the work ultimately contribute in any significant way to an understanding of the subject?

II.  Development of the Literature Review

Four Basic Stages of Writing 1.  Problem formulation -- which topic or field is being examined and what are its component issues? 2.  Literature search -- finding materials relevant to the subject being explored. 3.  Data evaluation -- determining which literature makes a significant contribution to the understanding of the topic. 4.  Analysis and interpretation -- discussing the findings and conclusions of pertinent literature.

Consider the following issues before writing the literature review: Clarify If your assignment is not specific about what form your literature review should take, seek clarification from your professor by asking these questions: 1.  Roughly how many sources would be appropriate to include? 2.  What types of sources should I review (books, journal articles, websites; scholarly versus popular sources)? 3.  Should I summarize, synthesize, or critique sources by discussing a common theme or issue? 4.  Should I evaluate the sources in any way beyond evaluating how they relate to understanding the research problem? 5.  Should I provide subheadings and other background information, such as definitions and/or a history? Find Models Use the exercise of reviewing the literature to examine how authors in your discipline or area of interest have composed their literature review sections. Read them to get a sense of the types of themes you might want to look for in your own research or to identify ways to organize your final review. The bibliography or reference section of sources you've already read, such as required readings in the course syllabus, are also excellent entry points into your own research. Narrow the Topic The narrower your topic, the easier it will be to limit the number of sources you need to read in order to obtain a good survey of relevant resources. Your professor will probably not expect you to read everything that's available about the topic, but you'll make the act of reviewing easier if you first limit scope of the research problem. A good strategy is to begin by searching the USC Libraries Catalog for recent books about the topic and review the table of contents for chapters that focuses on specific issues. You can also review the indexes of books to find references to specific issues that can serve as the focus of your research. For example, a book surveying the history of the Israeli-Palestinian conflict may include a chapter on the role Egypt has played in mediating the conflict, or look in the index for the pages where Egypt is mentioned in the text. Consider Whether Your Sources are Current Some disciplines require that you use information that is as current as possible. This is particularly true in disciplines in medicine and the sciences where research conducted becomes obsolete very quickly as new discoveries are made. However, when writing a review in the social sciences, a survey of the history of the literature may be required. In other words, a complete understanding the research problem requires you to deliberately examine how knowledge and perspectives have changed over time. Sort through other current bibliographies or literature reviews in the field to get a sense of what your discipline expects. You can also use this method to explore what is considered by scholars to be a "hot topic" and what is not.

III.  Ways to Organize Your Literature Review

Chronology of Events If your review follows the chronological method, you could write about the materials according to when they were published. This approach should only be followed if a clear path of research building on previous research can be identified and that these trends follow a clear chronological order of development. For example, a literature review that focuses on continuing research about the emergence of German economic power after the fall of the Soviet Union. By Publication Order your sources by publication chronology, then, only if the order demonstrates a more important trend. For instance, you could order a review of literature on environmental studies of brown fields if the progression revealed, for example, a change in the soil collection practices of the researchers who wrote and/or conducted the studies. Thematic [“conceptual categories”] A thematic literature review is the most common approach to summarizing prior research in the social and behavioral sciences. Thematic reviews are organized around a topic or issue, rather than the progression of time, although the progression of time may still be incorporated into a thematic review. For example, a review of the Internet’s impact on American presidential politics could focus on the development of online political satire. While the study focuses on one topic, the Internet’s impact on American presidential politics, it would still be organized chronologically reflecting technological developments in media. The difference in this example between a "chronological" and a "thematic" approach is what is emphasized the most: themes related to the role of the Internet in presidential politics. Note that more authentic thematic reviews tend to break away from chronological order. A review organized in this manner would shift between time periods within each section according to the point being made. Methodological A methodological approach focuses on the methods utilized by the researcher. For the Internet in American presidential politics project, one methodological approach would be to look at cultural differences between the portrayal of American presidents on American, British, and French websites. Or the review might focus on the fundraising impact of the Internet on a particular political party. A methodological scope will influence either the types of documents in the review or the way in which these documents are discussed.

Other Sections of Your Literature Review Once you've decided on the organizational method for your literature review, the sections you need to include in the paper should be easy to figure out because they arise from your organizational strategy. In other words, a chronological review would have subsections for each vital time period; a thematic review would have subtopics based upon factors that relate to the theme or issue. However, sometimes you may need to add additional sections that are necessary for your study, but do not fit in the organizational strategy of the body. What other sections you include in the body is up to you. However, only include what is necessary for the reader to locate your study within the larger scholarship about the research problem.

Here are examples of other sections, usually in the form of a single paragraph, you may need to include depending on the type of review you write:

• Current Situation : Information necessary to understand the current topic or focus of the literature review.
• Sources Used : Describes the methods and resources [e.g., databases] you used to identify the literature you reviewed.
• History : The chronological progression of the field, the research literature, or an idea that is necessary to understand the literature review, if the body of the literature review is not already a chronology.
• Selection Methods : Criteria you used to select (and perhaps exclude) sources in your literature review. For instance, you might explain that your review includes only peer-reviewed [i.e., scholarly] sources.
• Standards : Description of the way in which you present your information.
• Questions for Further Research : What questions about the field has the review sparked? How will you further your research as a result of the review?

IV.  Writing Your Literature Review

Once you've settled on how to organize your literature review, you're ready to write each section. When writing your review, keep in mind these issues.

Use Evidence A literature review section is, in this sense, just like any other academic research paper. Your interpretation of the available sources must be backed up with evidence [citations] that demonstrates that what you are saying is valid. Be Selective Select only the most important points in each source to highlight in the review. The type of information you choose to mention should relate directly to the research problem, whether it is thematic, methodological, or chronological. Related items that provide additional information, but that are not key to understanding the research problem, can be included in a list of further readings . Use Quotes Sparingly Some short quotes are appropriate if you want to emphasize a point, or if what an author stated cannot be easily paraphrased. Sometimes you may need to quote certain terminology that was coined by the author, is not common knowledge, or taken directly from the study. Do not use extensive quotes as a substitute for using your own words in reviewing the literature. Summarize and Synthesize Remember to summarize and synthesize your sources within each thematic paragraph as well as throughout the review. Recapitulate important features of a research study, but then synthesize it by rephrasing the study's significance and relating it to your own work and the work of others. Keep Your Own Voice While the literature review presents others' ideas, your voice [the writer's] should remain front and center. For example, weave references to other sources into what you are writing but maintain your own voice by starting and ending the paragraph with your own ideas and wording. Use Caution When Paraphrasing When paraphrasing a source that is not your own, be sure to represent the author's information or opinions accurately and in your own words. Even when paraphrasing an author’s work, you still must provide a citation to that work.

V.  Common Mistakes to Avoid

These are the most common mistakes made in reviewing social science research literature.

• Sources in your literature review do not clearly relate to the research problem;
• You do not take sufficient time to define and identify the most relevant sources to use in the literature review related to the research problem;
• Relies exclusively on secondary analytical sources rather than including relevant primary research studies or data;
• Uncritically accepts another researcher's findings and interpretations as valid, rather than examining critically all aspects of the research design and analysis;
• Does not describe the search procedures that were used in identifying the literature to review;
• Reports isolated statistical results rather than synthesizing them in chi-squared or meta-analytic methods; and,
• Only includes research that validates assumptions and does not consider contrary findings and alternative interpretations found in the literature.

Cook, Kathleen E. and Elise Murowchick. “Do Literature Review Skills Transfer from One Course to Another?” Psychology Learning and Teaching 13 (March 2014): 3-11; Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper . 2nd ed. Thousand Oaks, CA: Sage, 2005; Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination . Thousand Oaks, CA: Sage Publications, 1998; Jesson, Jill. Doing Your Literature Review: Traditional and Systematic Techniques . London: SAGE, 2011; Literature Review Handout. Online Writing Center. Liberty University; Literature Reviews. The Writing Center. University of North Carolina; Onwuegbuzie, Anthony J. and Rebecca Frels. Seven Steps to a Comprehensive Literature Review: A Multimodal and Cultural Approach . Los Angeles, CA: SAGE, 2016; Ridley, Diana. The Literature Review: A Step-by-Step Guide for Students . 2nd ed. Los Angeles, CA: SAGE, 2012; Randolph, Justus J. “A Guide to Writing the Dissertation Literature Review." Practical Assessment, Research, and Evaluation. vol. 14, June 2009; Sutton, Anthea. Systematic Approaches to a Successful Literature Review . Los Angeles, CA: Sage Publications, 2016; Taylor, Dena. The Literature Review: A Few Tips On Conducting It. University College Writing Centre. University of Toronto; Writing a Literature Review. Academic Skills Centre. University of Canberra.

Writing Tip

Break Out of Your Disciplinary Box!

Thinking interdisciplinarily about a research problem can be a rewarding exercise in applying new ideas, theories, or concepts to an old problem. For example, what might cultural anthropologists say about the continuing conflict in the Middle East? In what ways might geographers view the need for better distribution of social service agencies in large cities than how social workers might study the issue? You don’t want to substitute a thorough review of core research literature in your discipline for studies conducted in other fields of study. However, particularly in the social sciences, thinking about research problems from multiple vectors is a key strategy for finding new solutions to a problem or gaining a new perspective. Consult with a librarian about identifying research databases in other disciplines; almost every field of study has at least one comprehensive database devoted to indexing its research literature.

Frodeman, Robert. The Oxford Handbook of Interdisciplinarity . New York: Oxford University Press, 2010.

Another Writing Tip

Don't Just Review for Content!

While conducting a review of the literature, maximize the time you devote to writing this part of your paper by thinking broadly about what you should be looking for and evaluating. Review not just what scholars are saying, but how are they saying it. Some questions to ask:

• How are they organizing their ideas?
• What methods have they used to study the problem?
• What theories have been used to explain, predict, or understand their research problem?
• What sources have they cited to support their conclusions?
• How have they used non-textual elements [e.g., charts, graphs, figures, etc.] to illustrate key points?

When you begin to write your literature review section, you'll be glad you dug deeper into how the research was designed and constructed because it establishes a means for developing more substantial analysis and interpretation of the research problem.

Hart, Chris. Doing a Literature Review: Releasing the Social Science Research Imagination . Thousand Oaks, CA: Sage Publications, 1 998.

Yet Another Writing Tip

When Do I Know I Can Stop Looking and Move On?

Here are several strategies you can utilize to assess whether you've thoroughly reviewed the literature:

• Look for repeating patterns in the research findings . If the same thing is being said, just by different people, then this likely demonstrates that the research problem has hit a conceptual dead end. At this point consider: Does your study extend current research?  Does it forge a new path? Or, does is merely add more of the same thing being said?
• Look at sources the authors cite to in their work . If you begin to see the same researchers cited again and again, then this is often an indication that no new ideas have been generated to address the research problem.
• Search Google Scholar to identify who has subsequently cited leading scholars already identified in your literature review [see next sub-tab]. This is called citation tracking and there are a number of sources that can help you identify who has cited whom, particularly scholars from outside of your discipline. Here again, if the same authors are being cited again and again, this may indicate no new literature has been written on the topic.

Onwuegbuzie, Anthony J. and Rebecca Frels. Seven Steps to a Comprehensive Literature Review: A Multimodal and Cultural Approach . Los Angeles, CA: Sage, 2016; Sutton, Anthea. Systematic Approaches to a Successful Literature Review . Los Angeles, CA: Sage Publications, 2016.

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CHAPTER 2 REVIEW OF RELATED LITERATURE AND STUDIES

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How to Synthesize Written Information from Multiple Sources

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On This Page:

When you write a literature review or essay, you have to go beyond just summarizing the articles you’ve read – you need to synthesize the literature to show how it all fits together (and how your own research fits in).

Synthesizing simply means combining. Instead of summarizing the main points of each source in turn, you put together the ideas and findings of multiple sources in order to make an overall point.

At the most basic level, this involves looking for similarities and differences between your sources. Your synthesis should show the reader where the sources overlap and where they diverge.

Unsynthesized Example

Franz (2008) studied undergraduate online students. He looked at 17 females and 18 males and found that none of them liked APA. According to Franz, the evidence suggested that all students are reluctant to learn citations style. Perez (2010) also studies undergraduate students. She looked at 42 females and 50 males and found that males were significantly more inclined to use citation software ( p < .05). Findings suggest that females might graduate sooner. Goldstein (2012) looked at British undergraduates. Among a sample of 50, all females, all confident in their abilities to cite and were eager to write their dissertations.

Synthesized Example

Studies of undergraduate students reveal conflicting conclusions regarding relationships between advanced scholarly study and citation efficacy. Although Franz (2008) found that no participants enjoyed learning citation style, Goldstein (2012) determined in a larger study that all participants watched felt comfortable citing sources, suggesting that variables among participant and control group populations must be examined more closely. Although Perez (2010) expanded on Franz’s original study with a larger, more diverse sample…

Step 1: Organize your sources

After collecting the relevant literature, you’ve got a lot of information to work through, and no clear idea of how it all fits together.

Before you can start writing, you need to organize your notes in a way that allows you to see the relationships between sources.

One way to begin synthesizing the literature is to put your notes into a table. Depending on your topic and the type of literature you’re dealing with, there are a couple of different ways you can organize this.

Summary table

A summary table collates the key points of each source under consistent headings. This is a good approach if your sources tend to have a similar structure – for instance, if they’re all empirical papers.

Each row in the table lists one source, and each column identifies a specific part of the source. You can decide which headings to include based on what’s most relevant to the literature you’re dealing with.

For example, you might include columns for things like aims, methods, variables, population, sample size, and conclusion.

For each study, you briefly summarize each of these aspects. You can also include columns for your own evaluation and analysis.

The summary table gives you a quick overview of the key points of each source. This allows you to group sources by relevant similarities, as well as noticing important differences or contradictions in their findings.

Synthesis matrix

A synthesis matrix is useful when your sources are more varied in their purpose and structure – for example, when you’re dealing with books and essays making various different arguments about a topic.

Each column in the table lists one source. Each row is labeled with a specific concept, topic or theme that recurs across all or most of the sources.

Then, for each source, you summarize the main points or arguments related to the theme.

The purposes of the table is to identify the common points that connect the sources, as well as identifying points where they diverge or disagree.

Step 2: Outline your structure

Now you should have a clear overview of the main connections and differences between the sources you’ve read. Next, you need to decide how you’ll group them together and the order in which you’ll discuss them.

For shorter papers, your outline can just identify the focus of each paragraph; for longer papers, you might want to divide it into sections with headings.

There are a few different approaches you can take to help you structure your synthesis.

If your sources cover a broad time period, and you found patterns in how researchers approached the topic over time, you can organize your discussion chronologically .

That doesn’t mean you just summarize each paper in chronological order; instead, you should group articles into time periods and identify what they have in common, as well as signalling important turning points or developments in the literature.

If the literature covers various different topics, you can organize it thematically .

That means that each paragraph or section focuses on a specific theme and explains how that theme is approached in the literature.

Source Used with Permission: The Chicago School

If you’re drawing on literature from various different fields or they use a wide variety of research methods, you can organize your sources methodologically .

That means grouping together studies based on the type of research they did and discussing the findings that emerged from each method.

If your topic involves a debate between different schools of thought, you can organize it theoretically .

That means comparing the different theories that have been developed and grouping together papers based on the position or perspective they take on the topic, as well as evaluating which arguments are most convincing.

Step 3: Write paragraphs with topic sentences

What sets a synthesis apart from a summary is that it combines various sources. The easiest way to think about this is that each paragraph should discuss a few different sources, and you should be able to condense the overall point of the paragraph into one sentence.

This is called a topic sentence , and it usually appears at the start of the paragraph. The topic sentence signals what the whole paragraph is about; every sentence in the paragraph should be clearly related to it.

A topic sentence can be a simple summary of the paragraph’s content:

“Early research on [x] focused heavily on [y].”

For an effective synthesis, you can use topic sentences to link back to the previous paragraph, highlighting a point of debate or critique:

“Several scholars have pointed out the flaws in this approach.” “While recent research has attempted to address the problem, many of these studies have methodological flaws that limit their validity.”

By using topic sentences, you can ensure that your paragraphs are coherent and clearly show the connections between the articles you are discussing.

As you write your paragraphs, avoid quoting directly from sources: use your own words to explain the commonalities and differences that you found in the literature.

Don’t try to cover every single point from every single source – the key to synthesizing is to extract the most important and relevant information and combine it to give your reader an overall picture of the state of knowledge on your topic.

Step 4: Revise, edit and proofread

Like any other piece of academic writing, synthesizing literature doesn’t happen all in one go – it involves redrafting, revising, editing and proofreading your work.

Checklist for Synthesis

•   Do I introduce the paragraph with a clear, focused topic sentence?
•   Do I discuss more than one source in the paragraph?
•   Do I mention only the most relevant findings, rather than describing every part of the studies?
•   Do I discuss the similarities or differences between the sources, rather than summarizing each source in turn?
•   Do I put the findings or arguments of the sources in my own words?
•   Is the paragraph organized around a single idea?
•   Is the paragraph directly relevant to my research question or topic?
•   Is there a logical transition from this paragraph to the next one?

Further Information

How to Synthesise: a Step-by-Step Approach

Help…I”ve Been Asked to Synthesize!

Learn how to Synthesise (combine information from sources)

How to write a Psychology Essay

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How to Write a Psychology Essay

Home > USC Columbia > Arts and Sciences > Comparative Literature > Comparative Literature Theses and Dissertations

Comparative Literature Theses and Dissertations

Theses/dissertations from 2023 2023.

Constructing Selfhood Through Fantasy: Mirror Women and Dreamscape Conversations in Olga Grushin’s Forty Rooms , Grace Marie Alger

Eugene O’Neill Returns: Theatrical Modernization and O’Neill Adaptations in 1980s China , Shuying Chen

The Supernatural in Migration: A Reflection on Senegalese Literature and Film , Rokhaya Aballa Dieng

Breaking Down the Human: Disintegration in Nineteenth-Century Fiction , Benjamin Mark Driscol

Archetypes Revisited: Investigating the Power of Universals in Soviet and Hollywood Cinema , Iana Guselnikova

Planting Rhizomes: Roots and Rhizomes in Maryse Condé’s Traversée de la Mangrove and Calixthe Beyala’s Le Petit Prince de Belleville , Rume Kpadamrophe

Violence, Rebellion, and Compromise in Chinese Campus Cinema ----- The Comparison of Cry Me a Sad River and Better Days , Chunyu Liu

Tracing Modern and Contemporary Sino-French Literary and Intellectual Relations: China, France, and Their Shifting Peripheries , Paul Timothy McElhinny

Truth And Knowledge In A Literary Text And Beyond: Lydia Chukovskaya’s Sofia Petrovna At The Intersections Between Selves, Culture, And Paratext , Angelina Rubina

From Roland to Gawain, or the Origin of Personified Knights , Clyde Tilson

Theses/Dissertations from 2022 2022

Afro-Diasporic Literatures of the United States and Brazil: Imaginaries, Counter-Narratives, and Black Feminism in the Americas , David E. S. Beek

The Pursuit of Good Food: The Alimentary Chronotope in Madame Bovary , Lauren Flinner

Form and Voice: Representing Contemporary Women’s Subaltern Experience in and Beyond China , Tingting Hu

Geography of a “Foreign” China: British Intellectuals’ Encounter With Chinese Spaces, 1920-1945 , Yuzhu Sun

Truth and Identity in Dostoevsky’s Raskolnikov and Prince Myshkin , Gwendolyn Walker

Theses/Dissertations from 2021 2021

Postcolonial Narrative and The Dialogic Imaginatio n: An Analysis of Early Francophone West African Fiction and Cinema , Seydina Mouhamed Diouf

The Rising of the Avant-Garde Movement In the 1980s People’s Republic of China: A Cultural Practice of the New Enlightenment , Jingsheng Zhang

Theses/Dissertations from 2020 2020

L’ Entre- Monde : The Cinema of Alain Gomis , Guillaume Coly

Digesting Gender: Gendered Foodways in Modern Chinese Literature, 1890s–1940s , Zhuo Feng

The Deconstruction of Patriarchal War Narratives in Svetlana Alexievich’s The Unwomanly Face of War , Liubov Kartashova

Pushing the Limits of Black Atlantic and Hispanic Transatlantic Studies Through the Exploration of Three U.S. Afro-Latio Memoirs , Julia Luján

Taiwanese Postcolonial Identities and Environmentalism in Wu Ming-Yi’s the Stolen Bicycle , Chihchi Sunny Tsai

Games and Play of Dream of the Red Chamber , Jiayao Wang

Theses/Dissertations from 2019 2019

Convertirse en Inmortal, 成仙 ChéngxiāN, Becoming Xian: Memory and Subjectivity in Cristina Rivera Garza’s Verde Shanghai , Katherine Paulette Elizabeth Crouch

Between Holy Russia and a Monkey: Darwin's Russian Literary and Philosophical Critics , Brendan G. Mooney

Emerging Populations: An Analysis of Twenty-First Century Caribbean Short Stories , Jeremy Patterson

Time, Space and Nonexistence in Joseph Brodsky's Poetry , Daria Smirnova

Theses/Dissertations from 2018 2018

Through the Spaceship’s Window: A Bio-political Reading of 20th Century Latin American and Anglo-Saxon Science Fiction , Juan David Cruz

The Representations of Gender and Sexuality in Contemporary Arab Women’s Literature: Elements of Subversion and Resignification. , Rima Sadek

Insects As Metaphors For Post-Civil War Reconstruction Of The Civic Body In Augustan Age Rome , Olivia Semler

Theses/Dissertations from 2017 2017

Flannery O’Connor’s Art And The French Renouveau Catholique: A Comparative Exploration Of Contextual Resources For The Author’s Theological Aesthetics Of Sin and Grace , Stephen Allen Baarendse

The Quixotic Picaresque: Tricksters, Modernity, and Otherness in the Transatlantic Novel, or the Intertextual Rhizome of Lazarillo, Don Quijote, Huck Finn, and The Reivers , David Elijah Sinsabaugh Beek

Piglia and Russia: Russian Influences in Ricardo Piglia’s Nombre Falso , Carol E. Fruit Diouf

Beyond Life And Death Images Of Exceptional Women And Chinese Modernity , Wei Hu

Archival Resistance: A Comparative Reading of Ulysses and One Hundred Years of Solitude , Maria-Josee Mendez

Narrating the (Im)Migrant Experience: 21st Century African Fiction in the Age of Globalization , Bernard Ayo Oniwe

Narrating Pain and Freedom: Place and Identity in Modern Syrian Poetry (1970s-1990s) , Manar Shabouk

Theses/Dissertations from 2016 2016

The Development of ‘Meaning’ in Literary Theory: A Comparative Critical Study , Mahmoud Mohamed Ali Ahmad Elkordy

Familial Betrayal And Trauma In Select Plays Of Shakespeare, Racine, And The Corneilles , Lynn Kramer

Evil Men Have No Songs: The Terrorist and Literatuer Boris Savinkov, 1879-1925 , Irina Vasilyeva Meier

Theses/Dissertations from 2015 2015

Resurrectio Mortuorum: Plato’s Use of Ἀνάγκη in the Dialogues , Joshua B. Gehling

Two Million "Butterflies" Searching for Home: Identity and Images of Korean Chinese in Ho Yon-Sun's Yanbian Narratives , Xiang Jin

The Trialectics Of Transnational Migrant Women’s Literature In The Writing Of Edwidge Danticat And Julia Alvarez , Jennifer Lynn Karash-Eastman

Unacknowledged Victims: Love between Women in the Narrative of the Holocaust. An Analysis of Memoirs, Novels, Film and Public Memorials , Isabel Meusen

Making the Irrational Rational: Nietzsche and the Problem of Knowledge in Mikhail Bulgakov's The Master and Margarita , Brendan Mooney

Invective Drag: Talking Dirty in Catullus, Cicero, Horace, and Ovid , Casey Catherine Moore

Destination Hong Kong: Negotiating Locality in Hong Kong Novels 1945-1966 , Xianmin Shen

H.P. Lovecraft & The French Connection: Translation, Pulps and Literary History , Todd David Spaulding

Female Representations in Contemporary Postmodern War Novels of Spain and the United States: Women as Tools of Modern Catharsis in the Works of Javier Cercas and Tim O'Brien , Joseph P. Weil

Theses/Dissertations from 2014 2014

Poetic Appropriations in Vergil’s Aeneid: A Study in Three Themes Comprising Aeneas’ Character Development , Edgar Gordyn

Ekphrasis and Skepticism in Three Works of Shakespeare , Robert P. Irons

Theses/Dissertations from 2013 2013

The Role of the Trickster Figure and Four Afro-Caribbean Meta-Tropes In the Realization of Agency by Three Slave Protagonists , David Sebastian Cross

Putting Place Back Into Displacement: Reevaluating Diaspora In the Contemporary Literature of Migration , Christiane Brigitte Steckenbiller

Using Singular Value Decomposition in Classics: Seeking Correlations in Horace, Juvenal and Persius against the Fragments of Lucilius , Thomas Whidden

Theses/Dissertations from 2012 2012

Decolonizing Transnational Subaltern Women: The Case of Kurasoleñas and New York Dominicanas , Florencia Cornet

Representation of Women In 19Th Century Popular Art and Literature: Forget Me Not and La Revista Moderna , Juan David Cruz

53x+m³=Ø? (Sex+Me=No Result?): Tropes of Asexuality in Literature and Film , Jana -. Fedtke

Argentina in The African Diaspora: Afro-Argentine And African American Cultural Production, Race, And Nation Building in the 19th Century , Julia Lujan

Male Subjectivity and Twenty-First Century German Cinema: Gender, National Idenity, and the Problem of Normalization , Richard Sell

Theses/Dissertations from 2011 2011

Blue Poets: Brilliant Poetry , Evangelin Grace Chapman-Wall

Sickness of the Spirit: A Comparative Study of Lu Xun and James Joyce , Liang Meng

Dryden and the Solution to Domination: Bonds of Love In the Conquest of Granada , Lydia FitzSimons Robins

Theses/Dissertations from 2010 2010

The Family As the New Collectivity of Belonging In the Fiction of Bharati Mukherjee and Jhumpa Lahiri , Sarbani Bose

Lyric Transcendence: the Sacred and the Real In Classical and Early-Modern Lyric. , Larry Grant Hamby

Abd al-Rahman Al-Kawakibi's Tabai` al-Istibdad wa Masari` al-Isti`bad (The Characteristics of Despotism and The Demises of Enslavement): A Translation and Introduction , Mohamad Subhi Hindi

Re-Visions: Nazi Germany and Fascist Italy In German and Italian Film and Literature , Kristina Stefanic Brown

Plato In Modern China: A Study of Contemporary Chinese Platonists , Leihua Weng

Making Victims: History, Memory, and Literature In Japan's Post-War Social Imaginary , Kimberly Wickham

Theses/Dissertations from 2009 2009

The Mirrored Body: Doubling and Replacement of the Feminine and androgynous Body In Hadia Said'S Artist and Haruki Murakami'S Sputnik Sweetheart , Fatmah Alsalamean

Making Monsters: The Monstrous-Feminine In Horace and Catullus , Casey Catherine Moore

Not Quite American, Not Quite European: Performing "Other" Claims to Exceptionality In Francoist Spain and the Jim Crow South , Brittany Powell

Developing Latin American Feminist Theory: Strategies of Resistance In the Novels of Luisa Valenzuela and Sandra Cisneros , Jennifer Lyn Slobodian

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Thesis Acknowledgements Examples

5 Examples For Your Inspiration

By: Derek Jansen (MBA) | Reviewers: Dr Eunice Rautenbach | May 2024

The acknowledgements section of your thesis or dissertation is an opportunity to say thanks to all the people who helped you along your research journey. In this post, we’ll share five thesis acknowledgement examples to provide you with some inspiration.

Overview: Acknowledgements Examples

• The acknowledgements 101
• Example:  Formal and professional
• Example:  Warm and personal
• Example:  Challenge-centric
• Example:  Institution-centric
• Example:  Reflective and philosophical
• FREE Acknowledgements template

Acknowledgements 101: The Basics

The acknowledgements section in your thesis or dissertation is where you express gratitude to those who helped bring your project to fruition. This section is typically brief (a page or less) and less formal, but it’s crucial to thank the right individuals in the right order .

As a rule of thumb, you’ll usually begin with academic support : your supervisors, advisors, and faculty members. Next, you’ll acknowledge any funding bodies or sponsors that supported your research. You’ll then follow this with your intellectual contributors , such as colleagues and peers. Lastly, you’ll typically thank your personal support network , including family, friends, and even pets who offered emotional support during your studies.

As you can probably see, this order moves from the most formal acknowledgements to the least . Typically, your supervisor is mentioned first, due to their significant role in guiding and potentially evaluating your work. However, while this structure is recommended, it’s essential to adapt it based on any specific guidelines from your university. So, be sure to always check (and adhere to) any requirements or norms specific to your university.

With that groundwork laid, let’s look at a few dissertation and thesis acknowledgement examples . If you’d like more, check out our collection of dissertation examples here .

Need a helping hand?

Example #1: Formal and Professional

This acknowledgement formally expresses gratitude to academic mentors and peers, emphasising professional support and academic guidance.

I extend my deepest gratitude to my supervisor, Professor Jane Smith, for her unwavering support and insightful critiques throughout my research journey. Her deep commitment to academic excellence and meticulous attention to detail have significantly shaped this dissertation. I am equally thankful to the members of my thesis committee, Dr. John Doe and Dr. Emily White, for their constructive feedback and essential suggestions that enhanced the quality of my work.

My appreciation also goes to the faculty and staff in the Department of Biology at University College London, whose resources and assistance have been invaluable. I would also like to acknowledge my peers for their camaraderie and the stimulating discussions that inspired me throughout my academic journey. Their collective wisdom and encouragement have been a cornerstone of my research experience.

Finally, my sincere thanks to the technical staff whose expertise in managing laboratory equipment was crucial for my experiments. Their patience and readiness to assist at all times have left a profound impact on the completion of my project.

Example #2: Warm and Personal

This acknowledgement warmly credits the emotional and personal support received from family, friends and an approachable mentor during the research process.

This thesis is a reflection of the unwavering support and boundless love I received from my family and friends during this challenging academic pursuit. I owe an immense debt of gratitude to my parents, who nurtured my curiosity and supported my educational endeavours from the very beginning.

To my partner, Alex, your endless patience and understanding, especially during the most demanding phases of this research, have been my anchor. A heartfelt thank you to my supervisor, Dr. Mark Brown, whose mentorship extended beyond the academic realm into personal guidance, providing comfort and motivation during tough times.

I am also thankful for my friends, who provided both distractions when needed and encouragement when it seemed impossible to continue. The discussions and unwavering support from my peers at the university have enriched my research experience, making this journey not only possible but also enjoyable. Their presence and insights have been pivotal in navigating the complexities of my research topic.

Example #3: Inclusive of Challenges

This acknowledgement recognises the wide range of support received during unexpected personal and academic challenges, highlighting resilience and communal support.

The path to completing this dissertation has been fraught with both professional challenges and personal adversities. I am profoundly grateful for the enduring support of my supervisor, Dr. Lisa Green, whose steadfast belief in my capabilities and academic potential encouraged me to persevere even during my lowest moments. Her guidance was a beacon of light in times of doubt.

I must also express my deepest appreciation for my family, who stepped in not only with emotional reassurance, but also with critical financial support, when unexpected personal challenges arose. Their unconditional love and sacrifice have been the foundation of my resilience and success.

I am thankful, too, for the support services at the university, including the counselling centre, whose staff provided me with the tools to manage stress and maintain focus on my academic goals. Each of these individuals and institutions played a crucial role in my journey, reminding me that the pursuit of knowledge is not a solo expedition but a communal effort.

Example #4: Institution-Centric

This acknowledgement succinctly appreciates the financial, academic, and operational support provided by the university and its staff.

This dissertation would not have been possible without the generous financial support from the University of Edinburgh Scholarship Programme, which enabled me to focus fully on my research without financial burden. I am profoundly grateful to my advisor, Professor Richard Miles, for his sage advice, rigorous academic guidance, and the confidence he instilled in me. His expertise in the field of microbiology greatly enriched my work.

I would also like to thank the staff at the university library, whose assistance was indispensable. Their patience and willingness to help locate rare and essential resources facilitated a thorough and comprehensive literature review. Additionally, the administrative and technical staff, who often go unmentioned, provided necessary support that greatly enhanced my research experience. Their dedication and hard work create an environment conducive to academic success.

Lastly, my peers’ encouragement and the intellectual environment at the university have been vital in completing my research.

Example #5: Reflective and philosophical

This acknowledgement reflects on the philosophical growth and personal insights gained through the support of mentors, peers, and family, framing the dissertation as a journey of intellectual discovery.

Completing this thesis has been not only an academic challenge but also a profound journey of personal and philosophical growth.

I am immensely grateful to my mentor, Professor Sarah Johnson, for encouraging me to explore complex ideas and to challenge conventional wisdom. Her guidance helped me navigate the philosophical underpinnings of my research and deepened my analytical skills. My fellow students in the Philosophy Department provided a supportive and intellectually stimulating community. Our discussions extended beyond the classroom, offering new insights and perspectives that were crucial to my thesis.

I am also deeply thankful for my family, whose intellectual curiosity and spirited philosophical debates at home sparked my interest in philosophy from a young age. Their continuous support and belief in my academic pursuits have been instrumental in my success.

This dissertation reflects not only my work but also the collective support of everyone who has touched my life academically and personally. The journey has taught me the value of questioning and the importance of diverse perspectives in enriching our understanding of complex philosophical issues.

FREE Acknowledgements Template

To help fast-track your writing process, we’ve created a free, fully editable template . This template covers all the necessary content for a generic thesis or dissertation acknowledgements section. If you’re interested, you can download a copy here .

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• Print Friendly

• Open access
• Published: 10 May 2024

Contributions of elevated CRP, hyperglycaemia, and type 2 diabetes to cardiovascular risk in the general population: observational and Mendelian randomization studies

• Monica G Rolver 1 , 2 ,
• Frida Emanuelsson 1 , 2 ,
• Børge G Nordestgaard 1 , 2 , 3 , 4 &
• Marianne Benn 1 , 2  

Cardiovascular Diabetology volume  23 , Article number:  165 ( 2024 ) Cite this article

315 Accesses

Metrics details

To investigate the contributions of low-grade inflammation measured by C-reactive protein (CRP), hyperglycaemia, and type 2 diabetes to risk of ischemic heart disease (IHD) and cardiovascular disease (CVD) death in the general population, and whether hyperglycaemia and high CRP are causally related.

Research design and methods

Observational and bidirectional, one-sample Mendelian randomization (MR) analyses in 112,815 individuals from the Copenhagen General Population Study and the Copenhagen City Heart Study, and bidirectional, two-sample MR with summary level data from two publicly available consortia, CHARGE and MAGIC.

Observationally, higher plasma CRP was associated with stepwise higher risk of IHD and CVD death, with hazard ratios and 95% confidence intervals (95%CI) of 1.50 (1.38, 1.62) and 2.44 (1.93, 3.10) in individuals with the 20% highest CRP concentrations. The corresponding hazard ratios for elevated plasma glucose were 1.10 (1.02, 1.18) and 1.22 (1.01, 1.49), respectively. Cumulative incidences of IHD and CVD death were 365% and 592% higher, respectively, in individuals with both type 2 diabetes and plasma CRP ≥ 2 mg/L compared to individuals without either. Plasma CRP and glucose were observationally associated (β-coefficient: 0.02 (0.02, 0.03), p  = 3 × 10 − 20 ); however, one- and two-sample MR did not support a causal effect of CRP on glucose (−0.04 (−0.12, 0.32) and − 0.03 (−0.13, 0.06)), nor of glucose on CRP (−0.01 (−0.08, 0.07) and − 0.00 (−0.14, 0.13)).

Conclusions

Elevated concentrations of plasma CRP and glucose are predictors of IHD and CVD death in the general population. We found no genetic association between CRP and glucose, or vice versa, suggesting that lowering glucose pharmacologically does not have a direct effect on low-grade inflammation.

Hyperglycaemia and low-grade inflammation are both associated with type 2 diabetes and cardiovascular disease (CVD). Causality between plasma C-reactive protein (CRP) and glucose concentrations has not been determined. Clarifying causality might direct opportunities in prevention and treatment of diabetes and CVD.

We investigated whether plasma concentrations of CRP and glucose were causally associated and their associations with risk of ischemic heart disease (IHD) and CVD death.

Elevated plasma CRP and hyperglycaemia were both associated with increased risk of IHD and CVD death.

Plasma CRP and glucose concentrations were not causally associated.

Introduction

Type 2 diabetes, characterized by hyperglycaemia, affects millions of people worldwide and is a major risk factor of cardiovascular disease [ 1 , 2 , 3 ]. Chronic low-grade inflammation is a common feature in individuals with type 2 diabetes and is associated with high risk of atherosclerotic cardiovascular disease (CVD) [ 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. Hyperglycaemia has been shown to associate with increased concentrations of inflammatory markers such as plasma C-reactive protein (CRP) [ 11 , 12 , 13 , 14 ]. In turn, CRP and other proinflammatory markers have been associated with increased risk of hyperglycaemia and type 2 diabetes, as well as with ischemic heart disease (IHD) and CVD death [ 4 , 15 , 16 ]. Thus, low-grade inflammation has been proposed as a potential mechanism linking type 2 diabetes and cardiovascular disease. However, the extent to which low-grade inflammation and type 2 diabetes, independently and combined, add to the risk of IHD and CVD death is not known. Furthermore, it is not clear whether hyperglycaemia causally contributes to low-grade inflammation, whether low-grade inflammation casually contributes to hyperglycaemia, or both [ 17 , 18 , 19 , 20 ]. This is important, as ongoing randomized controlled trials of glucose-lowering drugs, i.e. semaglutide, are suggested to lower inflammation [ 17 ]. Also, several prospective studies have shown that individuals with higher CRP levels have higher risk of incident type 2 diabetes [ 21 , 22 , 23 ], indicating that low-grade inflammation may be a cause of diabetes. Conversely, so far, drugs targeted to lower inflammation has shown no effect on type 2 diabetes incidence [ 24 ].

Mendelian randomization (MR) is an epidemiological approach combining genetic information with traditional epidemiological methods to provide less confounded estimates compared to observational associations [ 25 ]. MR uses genetic variants strongly associated with a specific phenotype to compare the risk of an outcome in population subgroups stratified by the genotype. Due to the independent segregation of alleles from parents to offspring at conception, the population subgroups by genotype will differ systematically only in terms of the specific phenotype and confounding factors will be largely evenly distributed [ 25 ].

We investigated the contributions of type 2 diabetes and CRP ≥ 2 mg/L to the risk of IHD and CVD death and the potential causal relationship between hyperglycaemia and elevated CRP, using (i) observational analyses and bidirectional, one-sample MR analyses in 112,815 individuals from the Copenhagen City Heart Study and the Copenhagen General Population Study, and (ii) bidirectional two-sample MR analyses in up to 165,518 individuals using publicly available data on fasting glucose concentrations from the Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) [ 26 ] and on CRP concentrations in 204,402 individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Inflammation Working Group (CIWG) [ 27 ] (Supplementary Fig.  1 ).

Materials and methods

Study populations, copenhagen studies.

We included 112,815 individuals from the Copenhagen studies: the Copenhagen City Heart Study (CCHS) and the Copenhagen General Population Study (CGPS) for observational, one-sample, and two-sample (as a sensitivity analysis), bidirectional Mendelian randomization analyses. The CCHS and CPGS are both prospective population-based studies approved by the Danish National Committee on Health Research Ethics (approval numbers: H-KF-01-144/01, KF-100.2039/91, KF-01-144/01). Both were conducted according to the Declaration of Helsinki and written informed consent was obtained from all individuals. All individuals were white and of Danish descent and none were included in more than one study [ 28 ]. The CCHS was initiated in 1976 to 1978 with follow-up examinations in 1981 to 1983, 1991 to 1994, and 2001 to 2003. Individuals were selected at random from the national Danish Civil Registration System to reflect the Danish general population aged 20 to 100 + years. Linked to Danish health registries the follow-up time is up to 40 years. The CGPS was initiated in 2003 with enrolment until 2015 and ongoing follow-up examinations [ 4 ]. Participants in both studies filled in a questionnaire, which was reviewed with an examinator on the day of attendance. They also completed a physical examination and had a blood sample drawn [ 28 ]. 3,608 participants were excluded due to missing data on entry measurements of plasma glucose and CRP. Furthermore, 594 participants were excluded as they were registered with type 1 diabetes, resulting in a total of 4,202 individuals being excluded, corresponding to 3.5% of the cohort.

MAGIC and CHARGE CIWG consortia

Publicly available summary data for the selected genotypes were included for two-sample, bidirectional Mendelian randomization analyses. Beta-coefficients for fasting glucose concentrations from 165,518 to 200,392 individuals without diabetes and of European ancestry were used from the Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) [ 29 ]. Beta-coefficients for CRP concentrations in 204,402 individuals of European ancestry were used from the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Inflammation Working Group (CIWG) [ 27 ]. The MAGIC and CHARGE CIWG had partially overlapping sets of participants, accounting for up to 80% of the MAGIC participants and up to 65% of the CHARGE CIWG participants. Detailed information regarding overlapping participants is shown in Supplementary Table 1 .

A targeted selection approach of genetic variants was chosen to reduce the risk of pleiotropy [ 30 , 31 ]. Six genetic variants with well-established associations with high glucose and HbA 1c concentrations in genome wide association studies were selected as genetic instruments (rs560887, rs2191349, rs4607517, rs7903146, rs10811661, and rs11708067) [ 28 , 32 , 33 ]. The variants were selected as they represent independent loci showing strong associations between the genotype and glycemia and in genes known to be involved in glucose metabolism (Supplementary Table 2 ). The variants were not in linkage disequilibrium (R 2  = 0.004). Three genetic variants known to be associated with CRP in genome wide association studies were selected as genetic instruments (rs1205, rs3093077, and rs1130864) [ 4 , 15 , 34 ]. Theses variants are located in the CRP gene and were not in linkage disequilibrium (R 2  < 0.2) Detailed information regarding the genetic instruments are shown in Supplementary Table 3 . Information regarding linkage disequilibrium was retrieved from the web-based application LD-link [ 35 ]. In the Copenhagen studies, the variants were genotyped using an ABI PRISM 7900HT Sequence Detection System (Applied Biosystems Inc., Foster City, CA) and TaqMan-based assays. Large-scale sequencing (genotype arrays) in all individuals have not been performed in the Copenhagen studies.

Genetic variants for CRP and glucose were each combined into a weighted allele score, weighted by effect size on phenotype, i.e. plasma CRP and glucose, and allele frequency in the CCHS and CGPS combined. Only individuals with genotypes available for all variants of either CRP or glucose were included in genetic analyses, resulting in 105,759 individuals with a weighted allele score for CRP and 106,458 individuals with a weighted allele score for glucose (Supplementary Table 4 ).

C-reactive protein, glucose, and covariates

Blood samples were taken non-fasting and were measured fresh using standard hospital assays. Plasma CRP concentrations were measured using high sensitivity turbidimetry while plasma glucose, triglycerides, and high- and low-density lipoprotein cholesterol were measured by colorimetric assays. Blood samples were taken at random irrespective of time since and content of the last meal. Body mass index (BMI) was calculated by measured weight in kilograms divided by measured height in meters squared. Blood pressure was measured with automated equipment. Information on alcohol consumption in units per week, smoking, physical activity, and use of lipid-lowering medication were self-reported. Smoked pack-years were calculated as accumulated time of tobacco smoking and consumed tobacco per day in current and former smokers. Physical activity was categorized as low, medium, and high activity during work and leisure time.

Type 2 diabetes, ischemic heart disease, and cardiovascular death

Diagnoses of type 2 diabetes, ischemic heart disease (IHD) and cardiovascular disease death (CVD death) were as defined by the World Health Organization (WHO) International Classification of Disease (ICD)-10 and 8 codes (Supplementary Table 5 ). All diagnoses in the national Danish Patient Registry and the national Danish Cause of Death Registry are recorded by physicians in compliance with national laws. We did not lose track of any individual, as all individuals living in Denmark have a Danish Civil Registration System number, which is 100% complete including death and emigration.

Statistical analyses

We used Stata SE 17.0 for Windows (StataCorp). Deviation from Hardy-Weinberg equilibrium was investigated using chi-square tests. Test for trend across ordered weighted allele score categories for plasma CRP and glucose were by the non-parametric Cuzick’s extension of a Wilcoxon rank sum test. The population distribution of plasma CRP by diabetes-status and the population distribution of plasma glucose by CRP concentrations  <  or ≥ 2  mg/L were plotted using the kdensity function in Stata. To compare medians of plasma CRP and glucose between groups we used the non-parametric equality-of-medians test. CRP concentrations were not normally distributed and therefore log-transformed before incorporated into the regression models. The observational association between CRP and glucose was investigated using linear regression adjusted for age, sex, BMI, alcohol consumption, smoking status, physical activity, blood pressure, low-density lipoprotein cholesterol, triglycerides, and lipid-lowering medication and was graphically displayed using kernel-weighted local polynomial smoothing and geometric means with 95% confidence intervals. The same analyses were also performed stratified by sex and age.

Multivariable Cox proportional hazards regression models were used to estimate hazard ratios for the associations of plasma CRP and glucose concentrations with risk of IHD and CVD death. Graphs were truncated at glucose concentrations of 2.5 mmol/L (45 mg/dL) and individuals with lower concentrations were excluded from the Cox regression analyses because of a low number of individuals. The group with plasma glucose between 4.7 mmol/L (85 mg/dL) and 5.0 mmol/L (90 mg/dL) was used as reference group due to the normal physiological concentrations [ 36 ]. The models were adjusted for age, sex, BMI, alcohol consumption, smoking status, physical activity, blood pressure, low-density lipoprotein cholesterol, triglycerides, and lipid-lowering therapy.

The cumulative incidence of type 2 diabetes, IHD and CVD death as a function of age was plotted using a Kaplan-Meier estimator approach comparing the population divided into groups. The groups were categorized by diabetes-status ( type 2 diabetes or no type 2 diabetes ) and plasma CRP concentrations ( CRP < 2 mg/ L or CRP ≥ 2mg/L ). Log-rank tests were used to test for differences between groups. Cumulative incidence of CVD death was also estimated using competing risk regression based on Fine and Gray proportional sub-hazards model [ 37 ] accounting for the possibility of death from other cause as a competing event (Supplementary Fig.  2 ).

We next tested whether the selected genetic variants and the weighted allele score were associated with plasma CRP and glucose concentrations in the Copenhagen studies and used instrumental variable analysis with two-stage least-squares regression in bidirectional one-sample Mendelian randomization analysis to study the causal association between plasma CRP and plasma glucose, and vice versa, using the ivreg2 command. The strength of the genetic instrument (i.e. the association between weighted allele scores and glucose concentrations) was confirmed by F statistics in the first-stage regression [ 25 , 38 ]. Estimates were reported as average difference per 1 mg/dL higher CPR and 1 mmol/L (18 mg/dL) higher glucose concentration, respectively. The genetic analyses were not adjusted for any covariates as the allele scores are largely unconfounded. For independent confirmation, we also performed bidirectional two-sample Mendelian randomization analyses with publicly available data from the MAGIC and CHARGE consortia, using the same genetic variants for plasma CRP and glucose as in the one-sample analyses in the Copenhagen studies. The beta-coefficients for instrumented CRP and instrumented glucose, respectively, were combined using instrumental variable analyses with inverse variance weighted (IVW) regression. Sensitivity analyses accounting for direct pleiotropic effects (MR Egger) and for up to 50% of information coming from invalid or weak instruments (weighted median) were also performed using the publicly available, user-written mrmedian and mregger commands [ 39 , 40 ]. Heterogeneity was tested for using Cochran’s Q test and reported as I 2 , where an I 2 between 0 and 40% is considered low, between 40 and 60% as moderate and above 60% as high [ 41 ].

Baseline characteristics for all individuals, and for individuals with and without type 2 diabetes are shown in Supplementary Table 6 . Individuals with type 2 diabetes were older, more often women, had a higher BMI, and were more likely to be physically inactive compared to individuals without type 2 diabetes.

Observational associations between plasma glucose and C-reactive protein

Figure  1 shows the population distribution of plasma CRP in individuals with and without type 2 diabetes (a.), the population distribution of plasma glucose in individuals with plasma CRP < or ≥ 2 mg/L (b.), the multivariable adjusted correlation of plasma glucose as a function of plasma CRP (c.) and the cumulative incidence of type 2 diabetes stratified by plasma CRP < or ≥ 2 mg/L (d.). Median plasma CRP was 2.1 mg/L in individuals with type 2 diabetes and 1.4 mg/L in individuals without diabetes ( p  = 7 × 10 − 264 ) (a.). Median plasma glucose was 5.1 mmol/L (92 mg/dL) in individuals with a plasma CRP < 2 mg/L and 5.3 mmol/L (95 mg/dL) in individuals with a plasma CRP ≥ 2 mg/L ( p  = 6 × 10 − 146 ) (b.). In the multivariable adjusted model, there was a linear relationship between higher plasma CRP and higher plasma glucose ( p  = 3 × 10 − 20 ) (c.). The cumulative incidence of type 2 diabetes stratified by plasma CRP showed a gradually increasing risk of type 2 diabetes from age 40 in individuals with CRP ≥ 2 mg/L compared to CRP < 2 mg/L (d.).

Interrelationships between plasma C-reactive protein, plasma glucose, and diabetes in 110,746 individuals in the Copenhagen studies. (a) Population distribution of plasma C-reactive protein (CRP) in individuals with (red line) and without (green line) type 2 diabetes. (b) Population distribution of plasma glucose in individuals with a plasma CRP < 2 mg/L (green line) or a CRP ≥ 2 mg/L (red line). (c) Correlation between plasma CRP (blue line) and glucose concentration, adjusted for age, sex, body mass index, alcohol consumption, smoking status, physical activity, blood pressure, low-density cholesterol, triglycerides, and lipid-lowering therapy and displayed using kernel-weighted local polynomial smoothing and geometric means with 95% confidence intervals (grey area). (d) Cumulative incidence of type 2 diabetes as a function of age. The population was divided into two groups: CRP < 2 mg/L (blue line) and CRP ≥ 2 mg/L (red line). 1 mmol/L of glucose is equivalent to 18 mg/dL

For both plasma CRP and glucose, there was a linear association with higher age. Stratifying the analyses for sex showed higher plasma CRP with increasing plasma glucose concentrations in men compared to women (Supplementary Fig.  3 ).

Risk of ischemic heart disease and cardiovascular death

Figure  2 shows the prospective risk of IHD and CVD death as a function of higher CRP (a.) and glucose (b.) concentrations in quintiles. There was a stepwise increase in risk of IHD with hazard ratios (HR) in the 3rd-5th CRP quintiles from 1.11 (95% confidence interval: 1.02, 1.21) to 1.50 (1.38, 1.62) compared to the lowest quintile. Similarly, there was a stepwise increase in risk of CVD death with HR in the 3rd-5th CRP quintiles from 1.43 (1.12, 1.83) to 2.44 (1.93, 3.10). Overall risk of IHD and CVD death increased with increasing plasma CRP concentrations (p for trend = 1 × 10 − 22 and 7 × 10 − 14 ).

Mean plasma concentrations of C-reactive protein and glucose and hazard ratios (HRs) for ischemic heart disease (IHD) and cardiovascular disease (CVD) death in 112,815 individuals in the Copenhagen studies. Plasma C-reactive protein concentrations ( a. ) and plasma glucose concentrations ( b. ) are shown in quintiles. Individuals with a plasma glucose concentration below 2.5 mmol/L (45 mg/dL) were excluded. Risk estimates by Cox regression analyses were adjusted for age, sex, body mass index, alcohol consumption, smoking status, physical activity, blood pressure, low-density cholesterol, triglycerides, and lipid-lowering therapy. 1 mmol/L of glucose is equivalent to 18 mg/dL. SD = standard deviation, CI = confidence interval

In contrast, only a minor stepwise increased risk of IHD and CVD death was seen for the 3rd-5th glucose quintiles (p for trend = 0.02 and 0.04) with only individuals in the 5th glucose quintile being at increased risk of IHD and CVD death with HRs of 1.10 (1.02,1.18) and 1.22 (1.01,1.49).

Figure  3 shows the cumulative incidence of IHD (a.) and CVD death (b.) as a function of age and according to type 2 diabetes and low-grade inflammation status (CRP < or ≥ 2 mg/L). The cumulative incidence of IHD and CVD death increased stepwise from individuals with no type 2 diabetes and CRP < 2 mg/L, through individuals with no type 2 diabetes and a CRP ≥ 2 mg/L, individuals with type 2 diabetes and a CRP < 2 mg/L, and to individuals with both type 2 diabetes and a CRP ≥ 2 mg/L (p for trend = 2 × 10 − 56 and 2 × 10 − 20 ). At age 60 years, the lowest and highest risk (no type 2 diabetes and a CRP < 2 mg/L and both type 2 diabetes and a CRP ≥ 2 mg/L) categories had cumulative incidences of 5.2% and 19.0% for IHD, respectively, equivalent to a 365% increase in risk of IHD. At age 80, the corresponding lowest and highest risk factor scoring groups had cumulative incidences of 1.4% and 8.3% for CVD death, respectively, equivalent to a 592% increase in risk of CVD death.

Cumulative incidence of ischemic heart disease and cardiovascular disease death in 112,815 individuals in the Copenhagen studies. Cumulative incidence of ischemic heart disease (IHD; a. ) and cardiovascular disease death (CVD death; b. ) as a function of age and plotted as a Kaplan-Meier estimator. The population was divided into four categories: no type 2 diabetes (T2D) and C-reactive protein (CRP) < 2 mg/L (blue line); no T2D and CRP ≥ 2 mg/L (red line); T2D and CRP < 2 mg/L (green line); and T2D and CRP ≥ 2 mg/L (yellow line). Log-rank tests were used to examine for differences among ordered categories

Genetic associations between plasma glucose and C-reactive protein

Figure  4 a shows plasma CRP and glucose concentrations as a function of the genetic CRP and glucose allele scores on a continuous scale. The selected genetic variants for CRP and glucose were as weighted allele scores associated with respectively continuously higher plasma CRP and continuously higher glucose concentrations. The beta-coefficient of the regression of plasma CRP on CRP alleles was 2.92 ( p  = 4.1 × 10 − 75 ) and the regression of plasma glucose on glucose alleles was 0.97 ( p  = 8.3 × 10 − 102 ). The genetic CRP score explained 0.3% of the variation in plasma CRP in the population with an F-value = 445 (F > 10 indicates sufficient strength to ensure statistical reliability of the instrumental variable estimates [ 38 , 40 ]). The genetic glucose score explained 0.4% of the variation in plasma glucose in the population with an F-value = 1,255.

Genetic Mendelian randomization analyses in the Copenhagen studies and in CHARGE and MAGIC consortia. (a) Plasma C-reactive protein (CRP) and glucose concentrations as a function of, respectively, the weighted CRP and the glucose allele scores as continuous variables. The weighted CRP allele score was generated using the genetic variants rs1205, rs1130864, and rs3093077, located in the CRP gene. The weighted glucose allele score was generated using the genetic variants rs560887, rs2191349, rs4607517, rs7903146, rs10811661, and rs11708067. (b) Observational and Mendelian randomization analyses of the effect of a 1 mg/L higher plasma CRP on plasma glucose, or the effect of a 1 mmol/L (18 mg/dL) higher glucose on CRP. Observational results were obtained using multifactorially adjusted linear regressions and with 95% confidence intervals. Instrumental variable analyses with two-stage least-squares regression were used in one-sample Mendelian randomization. Inverse-variance weighted analyses were performed with publicly available data from the CHARGE and MAGIC consortia in two-sample Mendelian randomization. 1 mmol/L of glucose is equivalent to 18 mg/dL. CI = confidence interval, CCHS = Copenhagen City Heart Study, CGPS = Copenhagen General Population Study, CHARGE = The Cohorts for Heart and Aging Research in Genomic Epidemiology, MAGIC = the Meta-Analyses of Glucose and Insulin-related traits Consortium

Importantly, the CRP allele score did not associate with plasma glucose concentration (p = 0.34) and the glucose allele score did not associate with plasma CRP concentration (p = 0.27). The associations were also estimated with the mean plasma CRP and glucose concentrations as a function of the genetic CRP and glucose allele scores divided into quintiles showing similar results (Supplementary Fig.  4 ).

Observational versus genetic analyses

Figure  4 b shows the observational analyses, where a 1 mg/L higher plasma CRP level was associated with a 0.02 mmol/L (0.02, 0.03) (0.36 mg/dL) higher plasma glucose( p  = 3 × 10 − 20 ). A 1 mmol/L (18 mg/dL) higher plasma glucose level was associated with 0.04 mg/L (0.03, 0.05) higher plasma CRP( p  = 3 × 10 − 20 ). In the one-sample Mendelian randomization analyses, a 1 mg/L genetically determined higher plasma CRP level was not associated with plasma glucose ( p  = 0.27) and a 1 mmol/L (18 mg/dL) genetically determined higher plasma glucose level was not associated with plasma CRP ( p  = 0.88). Similarly, in the two-sample Mendelian randomization analyses, a 1 mg/L genetically determined higher plasma CRP concentration was not associated with plasma glucose ( p  = 0.47). A 1 mmol/L (18 mg/dL) genetically determined higher plasma glucose level was not associated with plasma CRP ( p  = 0.09). MR Egger and weighted median regressions showed similar results, with no indication of pleiotropy or heterogeneity (Supplementary Table 7 ) and two-sample MR within the Copenhagen studies showed similar results, also with no indication of pleiotropy or heterogeneity (Supplementary Table 8 ).

In this general population cohort, we found an observational association between elevated plasma C-reactive protein and glucose. We also found that CRP ≥ 2 mg/L associates with increased risk of type 2 diabetes, and that CRP ≥ 2 mg/L and type 2 diabetes, individually and jointly, contribute to stepwise higher risk of ischemic heart disease and cardiovascular death. However, bidirectional one- and two-sample genetic Mendelian randomization analyses did not support causality between CRP and glucose, indicating that inflammation and type 2 diabetes are correlated but independent risk factors of cardiovascular disease and death. These genetic findings are novel.

Several other studies have investigated the relationship between inflammatory markers such as CRP and IL-6, and glycaemic traits and type 2 diabetes using MR, however, the results are inconsistent [ 17 , 20 , 42 , 43 , 44 , 45 , 46 , 47 , 48 ]. A two-sample MR study investigated the genetic associations between type 2 diabetes, glycaemic traits, and CRP using 15 genetic variants associated with CRP, with 6 variants located in the CRP gene, and found a potential causal effect of CRP on risk of type 2 diabetes [ 42 ]. A smaller one-sample MR study found no causal effect of CRP on hyperglycaemia or insulin resistance, as measured by HbA1c and HOMA-IR [ 47 ]. The authors pointed to upstream inflammatory effectors as possible causal mediators as they observed a clear association between CRP and incident type 2 diabetes, but no indication of causality.

The effects of anti-inflammatory drugs on plasma glucose concentrations and the effects of glucose-lowering drugs on inflammatory markers have also been investigated. A recent exploratory analysis of four different phase 3 trials from the clinical development programs of both subcutaneous and oral semaglutide [ 17 ], a glucagon like peptide-1 receptor agonist, showed that semaglutide reduced CRP compared to comparator drugs in individuals with type 2 diabetes. In mediation analyses, the reduction was partially attributed to improved glycaemic control, which is not supported by our findings, and weight loss. The authors also suggested a direct effect of semaglutide on CRP. A randomized controlled trial(RCT) tested the effect of long-term anti-inflammatory treatment with low-dose aspirin and found no effect on risk of type 2 diabetes in women [ 49 ]. Another RCT tested the potential effects of canakinumab, an anti-inflammatory drug targeting interleukin-1β proven to prevent cardiovascular events, on fasting plasma glucose, HbA 1c , and risk of type 2 diabetes in individuals with prediabetes, previous myocardial infarction, and CRP > 2 mg/L [ 50 ]. The trial found an increased risk of type 2 diabetes with higher concentrations of CRP and IL-6. Canakinumab treatment reduced CRP and IL-6 concentrations, however, there was no effect on HbA 1c or risk of new-onset type 2 diabetes, supporting that low-grade inflammation is not causal for type 2 diabetes and that this treatment will not have effect on type 2 diabetes. Post hoc analyses from the same trial found that treatment with canakinumab reduced cardiovascular risk to a similar extent in patients with and without type 2 diabetes [ 24 ]. The implications of these findings are that reducing inflammation with drugs targeting inflammation, such as canakinumab may reduce risk of cardiovascular disease but not type 2 diabetes mellitus.

An observational study recently found an increased risk of vascular mortality in patients with type 2 diabetes and with CRP concentrations of 3.2–10 mg/L [ 16 ]. In the present study, we found increased risk of CVD death from mean plasma CRP concentrations above 1.4 mg/L, regardless of diabetes status (Fig.  2 ). The cumulative incidence of CVD death at age 80 years was comparable in individuals with a CRP ≥ 2 mg/L or with type 2 diabetes (3.7% or 4.0%, respectively). If both risk factors were present the cumulative incidence of CVD death was more than doubled(8.3%).

Strengths and limitations

The strengths of the present study include the comprehensive observational and bidirectional, one- and two-sample MR design. Investigating the risk of IHD and CVD death with a long follow-up period and potential bidirectional causality in the same cohort as well as with a two-sample design using publicly available summary data from two consortia, strengthens the results and reduces risk of confounding and pleiotropy. Furthermore, due to the updated Danish registries, no individuals were lost during follow-up and all deaths are confirmed.

Potential limitations to the MR analyses include population stratification, weak instrument bias and potential pleiotropic effects [ 51 , 52 ]. Our cohorts were ethnically homogenous, all individuals being white and of Danish descent in the Copenhagen studies and mainly of European decent in the MAGIC and CHARGE, hereby reducing population stratification bias. However, due to the homogenous study population, our results may not necessarily apply to other ethnicities. There was a considerable overlap between the datasets (MAGIC and CHARGE) used for the two-sample MR analyses, which may bias the estimates in the direction of the observational estimates (and in the same direction any potential bias in the one-sample MR analyses) [ 53 ]. However, the F statistic indicated sufficient strength of both genetic instruments in one-sample analyses, and the risk of a biased null finding due to overlapping samples in the two-sample analyses is low. MR Egger analyses did not indicate pleiotropy and Cochran’s Q test suggested low heterogeneity. Plasma glucose is in the Copenhagen Studies measured in the non-fasting state. However, the association between genetic glucose variants and plasma glucose concentrations were similar for the Copenhagen Studies and in MAGIC using fasting glucose (Supplementary Tables 7 and 8 ), and a similar stepwise effect is seen using haemoglobin A1c [ 54 ].

In conclusion, in this observational and bidirectional one- and two-sample Mendelian randomization study, we found that elevated concentrations of plasma CRP and glucose are predictors of IHD and CVD death in the general population. We found no genetic association between CRP and glucose, or vice versa, suggesting that lowering glucose pharmacologically does not have a direct effect on low-grade inflammation.

Data availability

Aggregated data from the Copenhagen City Heart Study and the Copenhagen General Population Study may be available on reasonable request to the corresponding author. Summary level data from the MAGIC and CHARGE consortia are publicly available.

Galicia-Garcia U, Benito-Vicente A, Jebari S, Larrea-Sebal A, Siddiqi H, Uribe KB, et al. Pathophysiology of type 2 diabetes Mellitus. Int J Mol Sci. 2020;21(6275):1–34.

Google Scholar  

Webber S. International Diabetes Federation. Diabetes Res Clin Pract. 2021;102(2):147–8.

Stumvoll M, Goldstein BJ, van Haeften TW. Type 2 diabetes: principles of pathogenesis and therapy. Lancet. 2005;365:1333–46.

Article   CAS   PubMed   Google Scholar  

Zacho J, Tybjærg-Hansen A, Jensen JS, Grande P, Sillesen H, Nordestgaard BG. Genetically Elevated C-Reactive Protein and Ischemic Vascular Disease. N Engl J Med [Internet]. 2008;359(18):1897–908. Available from: http://www.nejm.org/doi/abs/ https://doi.org/10.1056/NEJMoa0707402 .

Cushman M, Arnold AM, Psaty BM, Manolio TA, Kuller LH, Burke GL, et al. C-reactive protein and the 10-year incidence of coronary heart disease in older men and women: the cardiovascular health study. Circulation. 2005;112(1):25–31.

Ridker PM, Cushman M, Stampfer MJ, Tracy RP, Hennekens CH. Inflammation, aspirin, and the risk of cardiovascular disease in apparently healthy men. N Engl J Med [Internet]. 1997;336(14):973–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/9077376 .

Ridker PM, Hennekens CH, Buring JE, Rifai N. C-reactive protein and other markers of inflammation in the prediciton of cardiovascular disease in women. N Engl J Med. 2000;342:836–43.

Hu FB, Meigs JB, Li TY, Rifai N, Manson JE. Inflammatory markers and risk of developing type 2 diabetes in women. Diabetes [Internet]. 2004;53(3):693–700. Available from: http://www.ncbi.nlm.nih.gov/pubmed/14988254 .

Li Y, Zhong X, Cheng G, Zhao C, Zhang L, Hong Y et al. Hs-CRP and all-cause, cardiovascular, and cancer mortality risk: A meta-analysis. Atherosclerosis [Internet]. 2017;259:75–82. https://doi.org/10.1016/j.atherosclerosis.2017.02.003 .

Eiriksdottir G, Harris TB, Launer LJ, Gudnason V, Folsom AR, Andrews G, et al. Association between C reactive protein and coronary heart disease: mendelian randomisation analysis based on individual participant data. BMJ. 2011;342(7794):425.

Laaksonen DE, Salonen R. C-reactive protein and the development of the metabolic syndrome and diabetes in middle-aged men. Diabetologia. 2004;47:1403–10.

Hajer GR, Van Haeften TW, Visseren FLJ. Adipose tissue dysfunction in obesity, diabetes, and vascular diseases. Eur Heart J. 2008;29(24):2959–71.

De Rekeneire N, Peila R, Ding J, Colbert LH, Visser M, Shorr RI et al. Diabetes, Hyperglycemia, and Inflammation in Older Individuals Aging and Body Composition study From the. Diabetes Care [Internet]. 2006;29(8):1902–8. Available from: http://diabetesjournals.org/care/article-pdf/29/8/1902/593675/zdc00806001902.pdf .

Yeung SLA, Luo S, Schooling CM. The impact of glycated hemoglobin (HbA1c) on cardiovascular disease risk: a mendelian randomization study using UK Biobank. Diabetes Care. 2018;41(9):1991–7.

Article   CAS   Google Scholar  

Allin KH, Nordestgaard BG, Zacho J, Tybjærg-hansen A, Bojesen SE. C-Reactive protein and the risk of Cancer: a mendelian randomization study. J Natl Cancer Inst. 2010;102(3):202–6.

Sharif S, Van der Graaf Y, Cramer MJ, Kapelle LJ, de Borst GJ, Visseren FLJ, et al. Low-grade inflammation as a risk factor for cardiovascular events and all-cause mortality in patients with type 2 diabetes. Cardiovasc Diabetol. 2021;20(220):1–8.

Mosenzon O, Capehorn MS, De Remigis A, Rasmussen S, Weimers P, Rosenstock J. Impact of semaglutide on high-sensitivity C-reactive protein: exploratory patient-level analyses of SUSTAIN and PIONEER randomized clinical trials. Cardiovasc Diabetol [Internet]. 2022;21(1):172. https://doi.org/10.1186/s12933-022-01585-7 .

Ridker PM, Danielson E, Fonseca FAH, Genest J, Gotto AM, Kastelein JJP, et al. Rosuvastatin to prevent vascular events in men and women with elevated C-Reactive protein. N Engl J Med [Internet]. 2008;359(21):2195–207. Available from: www.nejm.org.

Pradhan AD, Cook NR, Buring JE, Manson JE, Ridker PM. C-Reactive protein is independently Associated with Fasting insulin in nondiabetic women. Arterioscler Thromb Vasc Biol. 2003;23:650–5.

Cheng L, Zhuang H, Yang S, Jiang H, Wang S, Zhang J. Exposing the causal effect of C-Reactive protein on the risk of type 2 diabetes Mellitus: a mendelian randomization study. Front Genet. 2018;9:657.

Article   CAS   PubMed   PubMed Central   Google Scholar  

Yang X, Tao S, Peng J, Zhao J, Li S, Wu N et al. High-sensitivity C-reactive protein and risk of type 2 diabetes: a nationwide cohort study and updated meta-analysis. Diabetes Metab Res Rev. 2021;37(8).

Lee CC, Adler AI, Sandhu MS, Sharp SJ, Forouhi NG, Erqou S, et al. Association of C-reactive protein with type 2 diabetes: prospective analysis and meta-analysis. Diabetologia. 2009;52(6):1040–7.

Tong KI, Hopstock LA, Cook S. Association of C-reactive protein with future development of diabetes: a population-based 7-year cohort study among Norwegian adults aged 30 and older in the Tromsø Study 2007–2016. BMJ Open. 2023;13(9).

Everett BM, Donath MY, Pradhan AD, Thuren T, Pais P, Nicolau JC, et al. Anti-inflammatory therapy with Canakinumab for the Prevention and Management of Diabetes. J Am Coll Cardiol. 2018;71(21):2392–401.

Lawlor DA, Harbord RM, Sterne JAC, Timpson N, Davey Smith G. Mendelian randomization: Using genes as instruments for making causal inferences in epidemiology. Stat Med [Internet]. 2008;27(8):1133–63. Available from: https://onlinelibrary.wiley.com/doi/10.1002/sim.3034 .

Chen J, Spracklen CN, Marenne G, Varshney A, Corbin LJ, Luan J et al. The trans-ancestral genomic architecture of glycemic traits. Nat Genet [Internet]. 2021;53(6):840–60. Available from: http://www.nature.com/articles/s41588-021-00852-9 .

Ligthart S, Vaez A, Võsa U, Stathopoulou MG, de Vries PS, Prins BP, et al. Genome Analyses of >200,000 Individuals Identify 58 Loci for Chronic Inflammation and Highlight Pathways that Link Inflammation and Complex Disorders. Am J Hum Genet [Internet]. 2018 Nov;103(5):691?706. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0002929718303203 .

Benn M, Tybjaerg-Hansen A, McCarthy M, Jensen G, Grande P, Nordestgaard B. Nonfasting glucose, ischemic heart Disease, and myocardial infarction. J Am Coll Cardiol. 2012;59(25):2356–65.

Chen J, Spracklen CN, Marenne G, Varshney A, Corbin LJ, Luan J, et al. The trans-ancestral genomic architecture of glycemic traits. Nat Genet. 2021;53(6):840–60.

Benn M, Nordestgaard BG. From genome-wide association studies to mendelian randomization: novel opportunities for understanding cardiovascular disease causality, pathogenesis, prevention, and treatment. Cardiovasc Res. 2018;114(9):1192–208.

CAS   PubMed   Google Scholar  

Swerdlow DI, Kuchenbaecker KB, Shah S, Sofat R, Holmes MV, White J, et al. Selecting instruments for mendelian randomization in the wake of genome-wide association studies. Int J Epidemiol. 2016;45(5):1600–16.

Article   PubMed   PubMed Central   Google Scholar  

Florez JC, Jablonski KA, Bayley N, Pollin TI, de Bakker PIW, Shuldiner AR, et al. TCF7L2 polymorphisms and progression to Siabetes in the diabetes Prevention Program. N Engl J Med. 2006;355(3):241–50.

Hribal ML, Presta I, Procopio T, Marini MA. Glucose tolerance, insulin sensitivity and insulin release in European non-diabetic carriers of a polymorphism upstream of CDKN2A and CDKN2B. Diabetologia. 2011;54:795–802.

Kathiresan S, Larson MG, Vasan RS, Guo C, Gona P, Keaney JF, et al. Contribution of clinical correlates and 13 C-Reactive Protein Gene Polymorphisms to interindividual variability in serum C-Reactive protein level. Circulation. 2006;113:1415–23.

Machiela MJ, Chanock SJ. LDlink: a web-based application for exploring population-specific haplotype structure and linking correlated alleles of possible functional variants. Bioinformatics. 2015;31(21):3555–7.

Global Health Observatory. Mean fasting blood glucose. World Heal Organ [Internet]. 2021;125–7. Available from: https://www.who.int/data/gho/indicator-metadata-registry/imr-details/2380 .

Fine JP, Gray RJ. A proportional hazards model for the subdistribution of a competing risk. J Am Stat Assoc. 1999;94(446):496–509.

Article   Google Scholar  

Burgess S, Thompson SG. Avoiding bias from weak instruments in mendelian randomization studies. Int J Epidemiol. 2011;40(3):755–64.

Article   PubMed   Google Scholar  

Bowden J, Smith GD, Burgess S. Mendelian randomization with invalid instruments: effect estimation and bias detection through Egger regression. Int J Epidemiol [Internet]. 2015 [cited 2017 Sep 15];512–25. Available from: https://academic.oup.com/ije/article-abstract/44/2/512/754653/Mendelian-randomization-with-invalid-instruments .

Bowden J, Davey Smith G, Haycock PC, Burgess S. Consistent estimation in mendelian randomization with some Invalid instruments using a weighted median estimator. Genet Epidemiol. 2016;40(4):304–14.

Higgins JPT. Measuring inconsistency in meta-analyses. BMJ [Internet]. 2003;327(7414):557–60. Available from: http://link.springer.com/10.1007/s10844-006-2974-4 .

Noordam R, Oudt CH, Bos MM, Smit RAJ, van Heemst D. High-sensitivity C-reactive protein, low-grade systemic inflammation and type 2 diabetes mellitus: A two-sample Mendelian randomization study. Nutr Metab Cardiovasc Dis [Internet]. 2018;28(8):795–802. https://doi.org/10.1016/j.numecd.2018.03.008 .

Wellen KE, Hotamisligil GS. Obesity-induced inflammatory changes in adipose tissue. J Clin Invest. 2003;112(12):1785–8.

Shoelson SE, Lee J, Goldfine AB. Inflammation and insulin resistance. J Clin Invest. 2006;116(7):1793–801.

Thorand B, Baumert J, Kolb H, Meisinger C, Chambless L, Koenig W, et al. Sex differences in the prediction of type 2 diabetes by inflammatory markers. Diabetes Care. 2007;30(4):854–60.

Wang X, Bao W, Liu J, Ouyang YY, Wang D, Rong S, et al. Inflammatory markers and risk of type 2 diabetes: a systematic review and meta-analysis. Diabetes Care. 2013;36(1):166–75.

Brunner EJ, Kivimä Ki M, Witte DR, Lawlor DA, Smith GD, Cooper JA et al. Inflammation, Insulin Resistance, and Diabetes - Mendelian Randomization Using CRP Haplotypes Points Upstream. PLoS Med [Internet]. 2008;5(8):1278–86. Available from: http://popgen.biol.ucl.ac.uk/software.html .

Timpson NJ, Lawlor DA, Harbord RM, Gaunt TR, Day IN, Palmer LJ, et al. C-reactive protein and its role in metabolic syndrome: mendelian randomisation study. Lancet. 2005;366(9501):1954–9.

Pradhan AD, Cook NR, Manson JE, Ridker PM, Buring JE. A randomized trial of low-dose aspirin in the prevention of clinical type 2 diabetes in women. Diabetes Care. 2009;32(1):3–8.

Ridker PM, Everett BM, Thuren T, MacFadyen JG, Chang WH, Ballantyne C, et al. Antiinflammatory therapy with Canakinumab for atherosclerotic disease. N Engl J Med. 2017;377(12):1119–31.

Smith GD, Ebrahim S. What can mendelian randomisation tell us about modifiable behavioural and environmental exposures? Br Med J. 2005;330(7499):1076–9.

Zheng J, Baird D, Borges M-C, Bowden J, Hemani G, Haycock P, et al. Recent developments in mendelian randomization studies. Curr Epidemiol Rep. 2017;4(4):330–45.

Burgess S, Davies NM, Thompson SG. Bias due to participant overlap in two-sample mendelian randomization. Genet Epidemiol. 2016;40(7):597–608.

Emanuelsson F, Afzal S, Jørgensen NR, Nordestgaard BG, Benn M. Hyperglycaemia, diabetes and risk of fragility fractures: observational and Mendelian randomisation studies. Diabetologia [Internet]. 2024;67(2):301–11. https://doi.org/10.1007/s00125-023-06054-8 .

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Acknowledgements

We thank the participants and staff of the Copenhagen City Heart Study and the Copenhagen General Population Study for their generous contributions. We also thank the participants in the MAGIC and CHARGE studies, and the investigators for making their data publicly available.

This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

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Department of Clinical Biochemistry, Copenhagen University Hospital - Herlev Gentofte, Borgmester Ib Juuls Vej 1, Herlev, 2730, Denmark

Monica G Rolver, Frida Emanuelsson, Børge G Nordestgaard & Marianne Benn

Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, Copenhagen, 2200, Denmark

Børge G Nordestgaard

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FE, BGN, and MB collected the data. MR and FE has analyzed the data and performed the statistical analyses. MR was a major contributor in writing the manuscript, which was revised by FE, BGN, and MB. All authors had access to the data and read and approved the final manuscript.

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Studies were approved by the Danish National Committee on Health Research Ethics (approval numbers: H-KF-01-144/01, KF-100.2039/91, KF-01-144/01).

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Monica Gylling Rolver is part-time employed by Novo Nordisk Denmark as a student assistant. Other authors report no conflict of interest related to the present study.

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Rolver, M.G., Emanuelsson, F., Nordestgaard, B.G. et al. Contributions of elevated CRP, hyperglycaemia, and type 2 diabetes to cardiovascular risk in the general population: observational and Mendelian randomization studies. Cardiovasc Diabetol 23 , 165 (2024). https://doi.org/10.1186/s12933-024-02207-0

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DOI : https://doi.org/10.1186/s12933-024-02207-0

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May 17, 2024

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More leptospirosis cases occur after floods, study shows

by K. W. Wesselink, University of Twente

A recent study, published by researchers at the Faculty of ITC in the International Journal of Health Geographics , has shown that flooding leads to increased leptospirosis cases.

First author, John Ifejube is a recent graduate of the master's program in Spatial Engineering. This publication is a direct result of his thesis on GeoHealth.

Flooding is a climate-related disaster that impacts not only the environment but also the well-being of people. Leptospirosis is a blood infection caused by the bacteria Leptospira. People become infected through interaction with contaminated water or urine.

Infected humans can get headaches, muscle pains, and fevers, but severe forms can lead to kidney failure. More and more studies link the spread of leptospirosis with floods, but it has not been extensively studied, until now.

Master's thesis

For his master's thesis, Ifejube conducted a study on the association between the incidence of leptospirosis and the occurrence of multiple floods in Kerala, India. He found that flooding leads to an increase in leptospirosis cases. His study reveals that flood duration is the most important characteristic of floods that can be used to predict the number of infections. According to his research, severe floods lead to more leptospirosis cases than moderate floods.

He compared leptospirosis cases across three different years in time and space. Specifically, he compared the number of cases in 2018 and 2019, which were years with heavy and moderate flooding respectively, to the number of cases in 2017, a year that did not experience any floods.

For each flood year, he looked at the reported cases three months before, during and three months after the flood. To assess the severity of floods, he determined the population exposed to each flood event using high-resolution satellite images. Finally, he used spatial regression to examine the relationship between post-flood cases and flood extents.

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