keywords in research article

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Title, Abstract and Keywords

The importance of titles.

The title of your manuscript is usually the first introduction readers (and reviewers) have to your work. Therefore, you must select a title that grabs attention, accurately describes the contents of your manuscript, and makes people want to read further.

An effective title should:

• Convey the  main topics  of the study
• Highlight the  importance  of the research
• Be  concise
• Attract  readers

Writing a good title for your manuscript can be challenging. First, list the topics covered by the manuscript. Try to put all of the topics together in the title using as few words as possible. A title that is too long will seem clumsy, annoy readers, and probably not meet journal requirements.

Does Vaccinating Children and Adolescents with Inactivated Influenza Virus Inhibit the Spread of Influenza in Unimmunized Residents of Rural Communities?

This title has too many unnecessary words.

Influenza Vaccination of Children: A Randomized Trial

This title doesn’t give enough information about what makes the manuscript interesting.

Effect of Child Influenza Vaccination on Infection Rates in Rural Communities: A Randomized Trial This is an effective title. It is short, easy to understand, and conveys the important aspects of the research.

Think about why your research will be of interest to other scientists. This should be related to the reason you decided to study the topic. If your title makes this clear, it will likely attract more readers to your manuscript. TIP: Write down a few possible titles, and then select the best to refine further. Ask your colleagues their opinion. Spending the time needed to do this will result in a better title.

Abstract and Keywords

The Abstract is:

• A  summary  of the content of the journal manuscript
• A time-saving  shortcut  for busy researchers
• A guide to the most important parts of your manuscript’s written content

Many readers will only read the Abstract of your manuscript. Therefore, it has to be able to  stand alone . In most cases the abstract is the only part of your article that appears in indexing databases such as Web of Science or PubMed and so will be the most accessed part of your article; making a good impression will encourage researchers to read your full paper.

A well written abstract can also help speed up the peer-review process. During peer review, referees are usually only sent the abstract when invited to review the paper. Therefore, the abstract needs to contain enough information about the paper to allow referees to make a judgement as to whether they have enough expertise to review the paper and be engaging enough for them to want to review it.

Your Abstract should answer these questions about your manuscript:

• What was done?
• Why did you do it?
• What did you find?
• Why are these findings useful and important?

Answering these questions lets readers know the most important points about your study, and helps them decide whether they want to read the rest of the paper. Make sure you follow the proper journal manuscript formatting guidelines when preparing your abstract.

TIP: Journals often set a maximum word count for Abstracts, often 250 words, and no citations. This is to ensure that the full Abstract appears in indexing services.

Keywords  are a tool to help indexers and search engines find relevant papers. If database search engines can find your journal manuscript, readers will be able to find it too. This will increase the number of people reading your manuscript, and likely lead to more citations.

However, to be effective, Keywords must be chosen carefully. They should:

• Represent  the content of your manuscript
• Be  specific  to your field or sub-field

Manuscript title:  Direct observation of nonlinear optics in an isolated carbon nanotube

Poor keywords:  molecule, optics, lasers, energy lifetime

Better keywords:  single-molecule interaction, Kerr effect, carbon nanotubes, energy level structure

Manuscript title:  Region-specific neuronal degeneration after okadaic acid administration Poor keywords:  neuron, brain, OA (an abbreviation), regional-specific neuronal degeneration, signaling

Better keywords:  neurodegenerative diseases; CA1 region, hippocampal; okadaic acid; neurotoxins; MAP kinase signaling system; cell death

Manuscript title:  Increases in levels of sediment transport at former glacial-interglacial transitions

Poor keywords:  climate change, erosion, plant effects Better keywords:  quaternary climate change, soil erosion, bioturbation

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• Writing Tips

How to Pick the Best Keywords for a Journal Article

3-minute read

• 27th October 2019

Once you’ve written an academic journal article, you may need to pick some keywords before submitting it for publication. These will help people find your work, so read our guide on how to pick keywords for a journal article.

Why Do I Need to Pick Keywords for My Article?

Academic publishers usually ask authors to pick a few keywords whenever they submit a paper. These ‘keywords’ are terms relevant to your article that people can search for on a  journal database .

Along with your title and  abstract , these keywords will impact how many people find, read, and cite your paper. It is therefore vital to give this issue a little thought. But how should you pick keywords for a journal article?

5 Tips on How to Select Keywords

To find the best keywords for a journal article, follow these tips.

1. Use the Publisher’s Guidelines

Check whether the journal’s publisher has any guidelines on how to select keywords. At the very least, they should provide advice on how many keywords are required (usually five to eight). These guidelines are often part of the author instructions, along with advice on writing style and formatting.

2. Focus on the Main Topic of Your Research

Use the main topic of your paper to guide keyword selection. For instance, if your paper is about the medical usage of nanotechnology, your keywords would include terms like “nanomedicine” and “nanopharmaceutics.” It can also help to consider what your target reader is likely to search for in a database.

3. Don’t Duplicate Words from Your Title

The   title of your paper is important partly because it will register on search engines. And since you can only pick a few keywords for your article, you should avoid duplicating any terminology already used in the paper’s title.

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4. Be Specific

Try to be as specific as possible. This may include using “key phrases” of two or three words, since single-word terms can be too ambiguous.

For instance, whereas “nanotechnology” would bring up every paper related to nanotechnology in any way, searching for a key phrase like “cancer nanotechnology” would only find papers specifically about cancer AND nanotechnology. Using specific keywords will therefore help readers with a specific interest in your subject area to find your paper.

5. Test Your Keywords

Finally, once you have selected some keywords, enter them into a relevant journal database. If they bring up articles on topics similar to your own, then you’ve selected good keywords. If not, you may need to try again.

In addition, if you’re struggling to come up with keywords that work, you can search for some articles that cover a similar subject. You can then check their keywords and use these to guide your own choices.

Summary: How to Select Keywords for a Journal Article

In summary, when selecting keywords for a journal article you should always:

• Follow the publisher’s guidelines for selecting keywords.
• Focus on terms related to the main topic of your research.
• Avoid duplicating words used in your title.
• Be specific and use multi-word “key phrases” where possible.
• Test your keywords on a relevant journal database.

Good luck! And let us know if you need help  proofreading your article .

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• Manuscript Preparation

How to Choose Keywords for a Manuscript?

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Table of Contents

Do you feel your article is being unnoticed? It can sometimes feel as if your work is sunk, in an ocean of millions of others, and not being found and read as often as you imagined. If this is the case, you are not alone. Unfortunately, in the internet era, just good research is hardly enough. A quality text edition of your manuscript and stunning presentations may be the next step for calling some attention, but making your work pop out from millions of others is a challenge that is often under thought by many researchers.

Actually, there are a few things in your power to help an article climb up search engine rankings. It all comes down to two concepts that you probably have heard a thousand times before: SEO and Keywords.

• Working with SEO (search engine optimization): Basically, this means helping search engines find your article relevant for certain search terms on the internet. This is done by choosing strategic keywords that correspond to words in the internet user’s search. This way your article has the best chance to appear in a higher position within a probably (very) long list of other related research.
• Choosing keywords for manuscripts: Keywords are words that capture the essence of your paper. They make your paper searchable (and findable!) and ensure that you get more citations. Therefore, it is important to include relevant keywords to help others find your paper. Don’t forget these simple tips, outlined below.

How to Select the Best Keywords for a Manuscript

The secret to choosing the best keywords for your manuscript is a matter of fine balance. On one hand, we recommend avoiding too many single-words (unless it is completely necessary) so that the search doesn’t render too unspecific. On the other hand, too many words may over-filter your article, making it more difficult to find.

There is also the tendency to add credibility to an article by selecting a lot of specialized keywords. However, that may actually dim the chances of your article being found. Rather than reducing your search chances to a specialized niche of experts, try to use more general terms used in literature to open your work to a more heterogeneous population.

Avoiding the duplication of words already in the article’s title is strongly recommended by journals. It is preferable to choose keywords that compliment the main topic of your research, including related words and/or methodology-specific terms.

Always remember to test your selected keywords. Do you think your article is difficult to find? Does the search pull up very similar articles to your own? Testing gives you the chance to tailor your keyword selection even further and, also very importantly, it can give you a valuable perspective of your “competitors.”

Making your article stand out is the ultimate challenge for its consumption. It might be daunting for researchers who feel overwhelmed by the digital world. However, don’t worry. Elsevier offers text editing services that not only provide excellent quality text for your manuscript, but also help you make the necessary amendments to fit it into your journal’s guidelines. This way, you are also ensuring that the keywords you chose as relevant line up with the journal’s requirements, making the whole process much easier.

Language Editing Services by Elsevier Author Services:

We know that, as an academic researcher, you have many things to do to stay relevant. Writing a manuscript is a crucial part of your endeavors.

That’s why we, at Elsevier Author Services, support you throughout your publication journey with a suite of products and services that help improve your manuscript before submission and beyond.

Check our video Reach the highest standard with Elsevier Author Services to learn more about Author Services.

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Keywords for Research Article: an Effective Guide

Table of Contents

With the myriad of online resources, it can be challenging to find relevant information.

Keywords are a way we can cut through the clutter and discover what we are looking for quickly. This is why incorporating the right keywords into articles, blogs, and websites is crucial. Identifying relevant  keywords for research articles  and incorporating them into your paper is the best way to ensure a top search engine ranking. 

The more an article aligns with the keywords a user searches for, the higher it will rank on SERPs. Optimizing your content with relevant keywords that match users’ search terms improves the visibility of your research paper.

This post details how to choose relevant keywords for your research article.

What Are Keywords in a Research Paper?

Keywords are words or phrases searchers type into search engines to find specific information .

In research papers, keywords are the terms that define a given topic and make it easier for searchers to find the content. Keywords help search engines match relevant search results with search queries, providing users with the most relevant and valuable information. 

Importance of Keywords in Research Papers

Keyword helps search engines decide which research article is most relevant to a search query.

When an Internet user wants to find something online, they typically enter a keyword that describes what they’re looking for. Search engine algorithm scans webpages to find those with similar or the exact keywords searched for. The more matches a content has with the user’s keywords, the more likely the article will appear in search engine results. 

The goal of every researcher is to get their article on the first page of the search engine results page (SERP). Discovering and incorporating the relevant keywords into your paper will improve your chances of higher rankings on search engines.

How to Choose the Best Keywords for Research Article

Choosing relevant keywords will improve your search engine rankings and ensure your research paper is found . Here are some tips for selecting the right keywords for your research paper.

1. Follow the Guidelines of Your Target Journal

Every journal has specifications when it comes to selecting keywords. Take the time to learn and follow your target journal’s instructions on keywords. For example, most clinical papers use terms drawn from the  US National Library of Medicine’s Medical Subject Headings (MeSH).  Other fields have their guidelines and requirements.

Most journals ask authors to present 5-8 terms. Some journals request only  single-word  keywords, making it easy for publishers and databases to organize the article, while others request phrases . Ensure you understand the guidelines for your target journal and follow them appropriately.

2. Identify Terms Related to Your Topic

Consider the terms researchers may use to search for papers related to your topic. For example, if your research article is on climate change , your keywords may include climate , global warming , earth , and biosphere . Target these keywords in your manuscript to ensure your research paper appears in the results of relevant searches.

3. Identify Terms That Summarize Your Work As a Whole

Identify and use keywords that represent and summarize your article as a whole. Some of these terms may be the main features of your paper, like population, setting, or variables.

Remember to keep an eye on the bigger picture as well. Identify the theories, processes, or concepts your paper covers, even if the specific names do not appear in your manuscript.

4. Include Your Techniques or Methodology

You may use key methods or experimental techniques your research revolves around as keywords. Be careful with spelling and capitalization, and also ensure that you use the officially recognized form of each key term. This is so your paper isn’t left out of searches for that keyword.

You can find the official, correct, and most commonly used versions of field-specific terms using Google Scholar.

5. Include Both Generic and Specific Terms

Avoid single-word keywords that are too general and vague. Make sure your keywords aren’t too long and not too short. Too short keywords will make the search unspecific. On the other hand, too-long keywords may filter your article to the point where it will be unindexed in search engines.

Use specific and general terms your potential readers will look for. For instance, if your article is on climate change , you may use general terms like “Global Warming” and “Earth.” And also more specific long-tail keywords relevant to your study.

6. Perform a Search to Test Your Keywords

Search Google and academic databases like Google Scholar for the keywords you want to submit. Do the keywords bring up articles similar to yours? If not, you may need to make some changes. 

This technique will also give you an idea of who your competition is. Examine the keywords they target to get ideas on how to refine your keyword list.

Keywords are an integral part of every research paper. They’re the means through which search engines determine which content is most relevant to a search query.

Choosing the most relevant keywords for your research topic is critical. The wrong choice of keywords can be detrimental to your article and even cost you opportunities to get read! On the other hand, the right keywords can improve your search engine rankings.

When choosing keywords, follow the instructions of your target journal. Identify terms related to your topic, including those that summarize your work as a whole. Also, consider using the techniques or methodology your research revolves around as keywords. Avoid only single-word keywords; instead, use both generic and specific terms. Finally, perform a search to test your keywords and refine your keyword list if necessary.

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Co-Founder of INK, Alexander crafts magical tools for web marketing. SEO and AI expert. He is a smart creative, a builder of amazing things. He loves to study “how” and “why” humans and AI make decisions.

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How to Find Keywords Effectively: Tools at a Glance

Academic research was once the domain of librarians in universities. Their expertise and ability to make analytical connections among and within fields of study played a critical role in the research process . While their expertise is still useful to researchers, keyword search results have replaced some of their functionality. Researchers can now find much of what they are looking for by plugging keywords into a search engine.

Keyword search results help researchers to find articles that are relevant to their own research interest. These results also let researchers know what other scientists are working on similar projects and what journals may accept their submissions. Conversely, authors will need to select appropriate keywords or phrases (“long tail keywords” – usually 3 words) to use in their work in order to increase readership.

Keyword Research Tools

First-time authors or those who simply prefer to employ technology can choose from a variety of keyword planners and other tools that help to analyze a document and select the keywords.

Medical Subject Headings (MeSH)

• MeSH on Demand – automatically identifies relevant MeSH terms from text using Natural Language Processing and the National Library of Medicine’s Medical Text Indexer
• The MeSH Browser – allows users to search directly for MeSH terms and conduct text-word searches of the Annotation and Scope Note fields of records

Google Keyword Planner

• Finds the keywords that are most pertinent to your field of study/area of interest
• Shows trends in keyword searches

Google Trends

• Shows how often a particular search-term is entered relative to the total search-volume across various regions of the world, and in various languages

Keyword Tool

• Generates long-tail keyword suggestions based on Google trends

Boolean Search

• Method of searching rather than a tool, per se
• Allows searchers to refine their search to specific pairings of words with the use of quotation marks and capitalization of “operators”
• Uses logical relationships between search term

All of these tools are based upon continuously changing and improving algorithms and claim to be reliable and effective. Add the expertise of a seasoned research librarian and authors can feel secure in their keyword selection process.

How to Select Keywords

Selecting keywords for research articles is not difficult, but it does take some strategizing. The most important component of the article is the title – “The search engine assumes that the title contains all of the important words that define the topic of the piece, and thus gives higher weightage to the words appearing there.” Therefore, the words of the title represent the main concepts of the article. In addition, the title should be clearly stated.

Keyword usage in the body of the article or abstract should follow these guidelines :

• Keywords should represent key concepts
• They should be descriptive
• Keywords should reflect a collective understanding of the topic
• Limit keywords/phrases to 3-4
• Use synonyms of keywords throughout
• Reuse keywords and phrases throughout article or abstract

The best keywords are proper names, specific procedures or techniques, outcome areas, capitalized events and eras, titles of books or articles, and definitions. Once keywords and phrases have been determined, the author will need to incorporate them into a well-written piece. Although it is useful to repeat keywords and phrases throughout the article, the repetition should not impair the article’s readability, which is paramount.

Another element to consider, potentially before any thought has been given to keywords and phrases, is the requirements of journal(s) to which the article will be submitted. Journals often have specific policies regarding submissions, including the usage of keywords. Online manuscript submission forms will generally have an area for keywords.

Online Visibility Impacts Citations

Another important aspect of keyword selection is its impact on citations. An article that is easy to find is more likely to be cited. Within the realm of citations and increasing online visibility, Google Scholar is a tool that allows users to search for digital or physical copies of articles. Results appear in order of the author’s ranking, the number of linked references, and their relevance to other scholarly literature. Furthermore, appearance of results are also based on ranking of the publication in which the article appears. This tool is useful when investigating an article’s position among others of similar content. Have you used the tools mentioned in this article for identifying good keywords? Do you have any suggestions for your peers? Please share your thoughts in the comments section below.

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Choosing Effective Keywords

• Research Process
• Peer Review
• Most journals require authors to select 4-8 keywords (or phrases) to accompany a manuscript to facilitate online searches
• In biomedical fields, MeSH terms are a good 'common vocabulary' to draw from
• Try Google Scholar to see what terms are most common in your field

Updated on April 8, 2014

As the volume of research output and the number of journals expand, identifying relevant studies in the literature is becoming increasingly challenging. To facilitate online article searches, most journals require authors to select 4-8 keywords (or phrases) to accompany a manuscript. Keywords may also be used to match a specific editor to a manuscript and to identify peer reviewers with related research interests. To maximize your manuscript's chances of a well-matched review and readership, here are three considerations when choosing key terms:

Your target journal's instructions for authors

Guidelines for the number and type of keywords may vary between journals. In certain cases, the editors will even provide a list of preferred terms, and clinical publications will often specifically request keywords drawn from the U.S. National Library of Medicine's collection of Medical Subject Headings (MeSH). The use of MeSH terms ensures that a “common vocabulary” is applied to index biomedical content, facilitating literature searches. In other cases, a journal may specify particular keywords that should not be used, such as words already included in your manuscript's title.

Your title, abstract, and main text

If your target journal does not exclude the use of keywords that are also employed in the title, you should seriously consider including this type of keyword. In particular, key terms that are shared with your manuscript title and/or abstract can help to increase the visibility of your study in article searches due to the algorithm used by many search engines. Crafting an effective, representative title is therefore critical. Additionally, search terms should accurately reflect the content of your main text; avoid words used only once or twice in the main text or not at all.

Your target audience

Your readers will likely search for terms that are commonly used in your field and related areas. You should thus avoid using esoteric terminology, such as an unusual abbreviation or a newly coined name for a technique, as keywords. However, very general search terms (such as “cell” or “PCR”), which may make it difficult for a researcher to find your article amid many other hits and for a journal to select an appropriate editor and peer reviewers, should also be omitted from the keyword list. The same is true for abbreviations that may have multiple meanings (such as “PLC,” which could stand for “phospholipase C” or “peptide-loading complex”). To identify potentially effective keywords, consider using Google Scholar or another engine to search for different commonly used, yet specific, terms and assessing how relevant the results are to your own work.

See our series of tips on using Google Scholar for more information.

We hope that we have provided useful guidance on choosing effective keywords for your manuscript. If you have any questions or comments, please contact us at [email protected] . Best wishes!

Michaela Panter, PhD

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Keyword Searching: Finding Articles on Your Topic: Select Keywords

Introduction to keywords.

Keywords, also commonly called search terms, are the words that you enter into the database search boxes. They represent the main concepts of your research topic and are the words used in everyday life to describe the topic. Without the right keywords, you may have difficulty finding the articles that you need.

Selecting keywords is a multi-step process that involves:

• identifying the main concepts of your topic
• brainstorming synonyms and antonyms that could also be used to describe your topic
• spell out abbreviations

It is very rare that your first search will bring back perfect results. It takes trial and error to determine which keywords work best for your topic. Be prepared to run multiple searches in your quest for the keywords that will help you find the materials you need.

Turn your topic into keywords

When doing an internet search in Google or Bing, you can enter your complete research question in the search box and get a bunch of results. However, if you enter your entire research question in the Library databases, you probably won't get any results. This is because the library databases look for the exact words that you enter in the search box(es). If the database can't find all of the words that you entered in the search boxes in the information about an article, it won't bring back any results. That's why it's important to search only for the main parts of your topic.  

Here is an example of a research question:

What is the relationship between test performance and the retention of ESL students?

The keywords for this topic are listed below:

• test performance
• ESL students

Avoid abstract or implied concepts

Because the databases search for the exact words that you enter, certain types of words can be unhelpful to include in your search. These include:

relationship words : words that get at the relationship between two topics

examples: compare, contrast, correlation, causation, relationship  

judgment words : words that judge something to be better or worse than something else

examples: best, worst, pro, con, advantages, disadvantages

There are many ways these ideas can be expressed or even implied. Using these words in your searches may exclude relevant articles on your topic simply because they don't include the exact word that you entered. By leaving out these words, you allow the database to find all of the articles on your main topics, which you can then evaluate to see if they fit your needs.

Synonyms & antonyms

Synonyms are words that have the same or similar meaning. Antonyms are words that have the opposite meaning. Both can be helpful when trying to determine relevant keywords for your research topic.

Some topics have many different terms that can be used to describe them. For example, here are some additional keywords that could be used for test performance :

• Tests     
• Exams     
• Test-Taking Skill
• Test Anxiety     
• Academic Achievement     
• Test Preparation

Sometimes when you are researching a specific topic, it can also be helpful to search for the opposite of your topic. For example, if you are interested in student retention, you'll also want to look at student dropouts . Here are some possible synonyms and antonyms for student retention :

• Student Persistence     
• Graduation     
• School Holding Power     
• Student Attrition     
• Dropout Prevention

Abbreviations

Abbreviations are shortened forms of words or phrases. For example, PTSD is an abbreviation for post-traumatic stress disorder. When searching the library databases, you'll always want to spell out abbreviations and search for the complete word or phrase. 

Searching for both the abbreviation and the complete word or phrase will help ensure you are finding all of the relevant results. You can do this by connecting the terms with OR.

Do not include parenthesis when searching for both the abbreviation and the full name.

Example: If you are looking for information on Cognitive Behavior Therapy (CBT), you would search for: Cognitive Behavior Therapy OR CBT

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Research Tips and Tricks

• Getting Started
• Understanding the Assignment
• Topic Selection Tips
• Narrowing Your Topic Tips

Major Terms

Keywords example, tools to help, videos about keywords.

• Developing A Search Strategy
• Scholarly vs Popular Sources
• What Are Primary Sources?
• Finding Scholarly Articles
• Finding Scholarly Books
• Finding Primary Sources
• Citing My Sources This link opens in a new window

When searching for resources,  DO NOT  enter the whole research question. 

Unlike a Google search, a journal article database cannot sort through all the words, and the results will be all over the place, or you will get no results.

The best method is to create a search strategy using keywords.

Begin by examining your research question to determine the major concepts or words with a specific meaning. These terms will form the basis of your search. 

When picking keywords avoid all minor words ("a," "an," or "the"), and prepositions or verb phrases ("on," "in," or "going to").

Also, use verbs (action words) and adjectives (descriptive words) sparingly.

For example, if your research question is:   

Does playing video games increase the chance that children will be violent?  

Words such as (does, the, that, chance, will, and be) don't have a specific meaning, so we can cross them out.  

Does playing video games increase the chance that children will be violent?

"Playing" is an action verb to describe what someone does with the game, and since there aren't other options, we can also cross this word off.  

Does   playing video games increase  the chance that  children  will be  violent?

While "increase" is getting at the relationship between violence and video games, if you include it, you will prejudice the results because you will be excluding results that talk about video games decreasing violence. 

Does   playing  video games increase  the chance that  children  will be  violent?

In the end, we are left with three major concepts in the sentence are:   

Video Games

Children  

Now you can develop these concepts into search terms that you can use do develop your search strategy.

A variety of words may describe your keywords, so you should brainstorm possible synonyms for them.  For example, children and youth are two different words used to describe a similar concept (human beings under the age of 18).  If you only entered the term "children" into a search of a database, then you would miss all the articles that deal with "youth."  To maximize the number of results you will get in a search, you need to include synonyms. Here is a list of possible synonyms of the keywords we identified:

If you need help generating synonyms for your keywords, try a few searches and look at the language the papers use or look at a thesaurus.

Source  and Source

• Worksheet This worksheet will help you generate keywords.
• Choosing and Using Keywords
• Selecting & Using Keywords
• One Perfect Source?

• << Previous: Narrowing Your Topic Tips
• Next: Developing A Search Strategy >>
• Last Updated: Apr 9, 2024 10:45 AM
• URL: https://kingsu.libguides.com/research

Research Paper Keyword Generator + Tips

• 🤩 Pros of Our Keyword Generator
• 🗝️ What Are Keywords?
• ️🔍 How to Choose Keywords
• 💡 4 Best Tips for Writing Keywords

🔗 References

🤩 pros of our free research paper keyword generator.

Our tool will present you with a list of keywords and phrases from any text you paste. There are several features that make it stand out from similar instruments:

🗝️ What Are Keywords in a Research Paper?

Keywords are phrases and words that reflect a research papers’ main ideas and topics . They help search engines and readers alike to quickly understand what the work is about. Such terms and phrases also allow researchers interested in your subject to promptly find your paper, share it, and cite it. Depending on the format of your work, keywords can be placed in its metadata or the abstract .

Why Are Keywords Important?

Oftentimes, students and professionals alike don’t take the time to choose the keywords for their research papers. They might be under the impression that if the work is good enough, others will find it anyway. In reality, that is not the case.

Choosing the most appropriate keywords has the following advantages:

• More precise search results . It ensures that your papers will be quickly found in search engines and academic registries. This way, researchers and other people interested in the topic have a better chance of coming across your work.
• Showing the paper’s relevance . Key words and phrases get across the main subject of the paper, summarize the main ideas , and make it easier for people to determine if they may be interested in the research.
• Quick communication with evaluators . Having keywords in your work lets your professors quickly comprehend the content and subject of your study.

🔍 How to Choose Keywords in Research Papers

This section will give you an understanding of the general rules about choosing keywords for academic works. There are several things we advise keeping in mind:

• Check the instructions . Before adding keywords, carefully read manuals provided by your professors or scientific journals. These materials should contain the volume of allowed keywords (3–5 on average, up to 10 in rare cases) and explain whether these should be picked from a pre-selected list.
• Choose specific words and phrases . When selecting your keywords, it is best not to use generic phrases. You should avoid abstract concepts or common words, since they can cause your paper to get lost in the search results. Instead, it is best to stay specific to the subject matter. For example, if you write about heart disease, use keys such as “ peripheral arterial disease ” or “acute coronary heart disease.”
• Search for optimized terms . Maximize the paper’s reach by optimizing terms. Google Scholar is a great way to discover the proper terminology for research in different fields.
• Include the methodology . Additionally, it’s essential to name the methodology used in the study. For example, regarding medicine, clinical trial types or experimental techniques are a perfect choice for papers on this subject.

Keywords Format: APA Style

APA is currently one of the most used formats for academic research papers. There are several things students should be aware of when writing works that follow its guidelines.

💡 4 Best Tips for Writing Keywords for Your Research

Finding and incorporating the right keywords in research studies takes time and effort to perfect. We’ve decided to give several tips that will help you hone your research and article-writing skills .

• Avoid keywords that are too narrow or too broad . This is one of the trickiest things to pull off while looking for the perfect keywords. Make them excessively precise, and you will narrow your audience significantly. Make them too broad, and the article will be lost in search results.
• Steer clear of obscure search terms . If you want the work to appear in academic directories, don’t use terms people rarely seek. For example, people rarely search for Latin animal or plant species names, so keep things closer to plain English.
• Don’t mislead readers . Don’t use keys unrelated to your topic to get into the search results. Such things remove credibility from your writing and add unnecessary difficulties for people trying to find it.
• Use the appropriate format . When choosing your keywords, it is best to remember several general rules. For example, you should try avoiding abbreviations where possible. Additionally, it is best to use short phrases rather than singular words.

Our research paper generator will become a valuable tool for your academic pursuits. Also, we recommend you try our effective plagiarism checker ! If you have any questions, check out our FAQ section.

❓ Research Paper Keyword Generator – FAQ

• Consider words and phrases that expand or narrow the paper’s scope.
• Use phrases instead of single words without context.
• Avoid abbreviations.
• Check the guidelines.
• Find short phrases.
• Use general terms.
• Stay specific.
• Mention the methodology.

Updated: Oct 30th, 2023

• How to Write a Research Paper. – Lebanon Valley College
• Keyword Searching: Finding Articles on Your Topic: Select Keywords. – Walden University
• Research Foundations: Choose Keywords. – Seminole State College Library
• Guidelines for Selecting Keywords. – Kansas State University
• A Guide to Writing an Effective Abstract / Selecting Keywords for Discovery. – Cambridge University Press & Assessment
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On this page, you will find an effective research paper keyword generator, which will make your task much more manageable. Additionally, you can use our valuable materials that will assist you in determining which words and phrases are perfect for your research.

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Keywords, discoverability, and impact

Editors' Note: Keywords will improve the article impact and are now necessary for Journal of the Medical Library Association articles. Here is a brief editorial with background information.

When the editor of the Journal of the Medical Library Association (JMLA) asked me to write a piece about author keywords in MEDLINE structured abstracts [ 1 ], the first thing I did was search for “keywords” in Google and Google Scholar. This exercise was reminiscent of the lithograph Drawing Hands by M. C. Escher [ 2 ]. Think about it. I used Google, an über-web search engine, to write keywords to find keywords. Google and Google Scholar returned a deluge of information (721 million and 4.35 million hits, respectively). Not surprisingly, at the top of the first page in Google were hits for Google AdWords and their Keyword Planner Tool [ 3 ].

I then did more focused searches in the ACL Anthology, a digital archive of papers in computational linguistics, and in Scientometrics or journals with similar coverage to confirm that keyword analysis is thriving in the text-mining and bibliometrics communities; for example, see Ventura and Silva [ 4 ] or Yao et al. [ 5 ].

Despite the circularity of my initial searches and too narrow follow-up attempts, I learned that the meaning of the concept varies depending on the domain. For example, in the search engine optimization (SEO) domain, keywords are terms that improve page rank. Shrewd selection and placement of words or phrases visible to the user or buried in hypertext markup language (HTML) can move a hit toward the top of a list returned by a search engine. Regarding these terms, the world of SEO has some curious neologisms, such as spamdexing, which refers to keyword stuffing, search engine spam, or black-hat SEO [ 6 ]. In contrast, white-hat SEO is ethical; its practitioners eschew black-hat techniques. In corpus linguistics, keywords discriminate between collections of documents to identify what is unique about, say, general versus scientific prose, or British versus American English [ 7 ]. Text miners and other computational scientists extract informative keywords to classify documents or improve retrieval.

This brings us to why you, as an author, should carefully consider the list of keywords that you will assign to your JMLA article and its relationship to your title and abstract. Think of optimization principles for discoverability of your article beyond MEDLINE and potential effects on the impact of your work. Overall, enhancing discoverability of JMLA articles should improve journal visibility, subsequent citation counts, and its impact. This is a desirable outcome for you and the profession.

Discoverability could depend on how well the title, abstract, and keyword list form a miniaturized version of your paper. This is why a good structured abstract resembles a paper written in the “Introduction, Methods, Results And Discussion” (IMRAD) format (see Cooper's editorial in the April 2015 JMLA ). The title includes the most important concepts in your paper and, ideally, the study design; the abstract summarizes the components of your paper; and the keyword list includes relevant concepts but with more detail than in the title. If keywords are too broad or too narrow, they are useless. All three pieces are important because web search engines and text-mining applications target these sections and sometimes overweight text, depending on location. Additionally, when presented to the reader, the title, abstract, and keyword list must be laden with relevant information to capture attention.

To write the keyword list for the JMLA , channel your inner indexer. Select the Medical Subject Headings (MeSH) that best characterize your topic to improve retrieval in MEDLINE [ 8 ]. Additionally, find words and phrases not covered by MeSH but known to practitioners and researchers in your field. The MeSH terms you proffer could improve decisions that a National Library of Medicine human indexer makes—after all, you are likely to know more about the topic of your paper than the indexer does. Adding non-MeSH terms could improve discoverability of your article by web search engines and by users who search digital repositories aside from PubMed and PubMed Central.

For example, in a recent paper we wrote for the JMLA on building gold standard datasets as a prelude to developing search filters [ 9 ], my coauthors and I reported that “oral squamous cell carcinoma” is not covered by MeSH, even though it is the most common cancer of the oral cavity. However, the term is a synonym for “mouth squamous cell carcinoma” in Emtree, the controlled vocabulary for Embase [ 10 ]. It also appears in the National Cancer Institute Thesaurus as “oral cavity squamous cell carcinoma” [ 11 ]. Any of these terms would have been good keywords for our paper.

In sum, if terms from controlled vocabularies beyond MeSH seem useful, consider adding them to your keyword list. Additionally, consider free-text terms for which users are likely to search. By carefully constructing your title, abstract, and keyword list, you will enhance discoverability of your article and its potential impact.

How to Do Keyword Research for SEO: A Beginner's Guide

Published: April 04, 2024

While Google keeps us on our toes with all the algorithm updates they keep rollin' out, one thing has stayed pretty consistent for inbound marketers looking to optimize their websites for search: keyword research.

In this post, we’ll define what keyword research is, why it’s important, how to conduct your research for your SEO strategy, and choose the right keywords for your website.

Table of Contents

What is keyword research?

Why is keyword research important, elements of keyword research, how to research keywords for your seo strategy, how to find and choose keywords for your website.

Keyword research is the process of finding and analyzing search terms that people enter into search engines with the goal of using that data for a specific purpose, often for search engine optimization (SEO) or general marketing. Keyword research can uncover queries to target, the popularity of these queries, their ranking difficulty, and more.

Keyword research helps you find which keywords are best to target and provides valuable insight into the queries that your target audience is actually searching on Google.

Insights from these actual search terms can help inform your content strategy as well as your larger marketing strategy.

People use keywords to find solutions when conducting research online.

So if your content is successful in getting in front of your audience as they conduct searches, you stand to gain more traffic. Therefore, you should be targeting those searches with content that features those keywords in a meaningful way.

Additionally, inbound methodology focuses less on creating content around what we want to tell people. Instead, we should be creating content around what people want to discover.

In other words, our audience is coming to us for helpful content that provides the answers they’re looking for.

In a nutshell, all of this starts with keyword research.

Conducting keyword research has many benefits, the most popular being:

Marketing Trend Insight

Conducting effective keyword research can provide you with insights into current marketing trends and help you center your content on relevant topics and keywords your audience is in search of.

Traffic Growth

When you identify the best-fitting keywords for the content you publish, the higher you’ll rank in search engine results — the more traffic you’ll attract to your website.

Customer Acquisition

If your business has content that other business professionals are looking for, you can meet their needs and provide them with a call-to-action that will lead them into the buyer journey from the awareness stage to the point of purchase.

By researching keywords for their popularity, search volume, and general intent, you can tackle the questions that most people in your audience want answers to.

Keywords vs. Topics

More and more, we hear how much SEO has evolved over just the last 10 years and how seemingly unimportant keywords have transformed our ability to rank well for the searches people make every day.

And to some extent, this is true, but in the eyes of an SEO professional, it’s a different approach. Rather, it’s the intent behind that keyword and whether or not a piece of content solves for that intent (we’ll talk more about intent in just a minute).

But that doesn’t mean keyword research is an outdated process. Let me explain:

Keyword research tells you what topics people care about and, assuming you use the right SEO tool, how popular those topics actually are among your audience.

The operative term here is topics, plural. By researching keywords that are getting a high volume of searches per month, you can identify and sort your content into topics or buckets that you want to create content on.

Then, you can use these topics to dictate which keywords you look for and target.

Keyword Research Template

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• Search Volume
• Keyword Difficulty

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There are three main elements I have discovered that you should pay attention to when conducting keyword research.

1. Relevance

Google ranks content for relevance.

This is where the concept of search intent comes in. Your content will only rank for a keyword if it meets the searchers’ needs.

In addition, your content must be the best resource out there for the query. After all, why would Google rank your content higher if it provides less value than other content that exists on the web?

2. Authority

Google will provide more weight to sources it deems authoritative.

That means you must do all you can to become an authoritative source by enriching your site with helpful, informative content and promoting that content to earn social signals and backlinks.

If you’re not seen as authoritative in the space, or if a keyword’s SERPs are loaded with heavy sources you can’t compete with (like Forbes or The Mayo Clinic), you have a lower chance of ranking unless your content is exceptional.

You may end up ranking on the first page for a specific keyword, but if no one ever searches for it, it will not result in traffic to your site. It's like setting up a shop in a ghost town.

Volume is measured by MSV (monthly search volume), which means the number of times the keyword is searched per month across all audiences.

• Make a list of important, relevant topics based on what you know about your business.
• Fill in those topic buckets with keywords.
• Understand how intent affects keyword research and analyze accordingly.
• Research related search terms.
• Use keyword research tools to your advantage.

I’m going to lay out a keyword research process you can follow to help you come up with a list of terms you should be targeting.

That way, you’ll be able to establish and execute a strong keyword strategy that helps you get found for the search terms you actually care about.

Step 1. Make a list of important, relevant topics based on what you know about your business.

To kick off this process, think about the topics you want to rank for in terms of generic buckets.

You’ll come up with about five to 10 topic buckets you think are important to your business, and then you’ll use those topic buckets to help come up with some specific keywords later in the process.

If you’re a regular blogger, these are probably the topics you blog about most frequently. Or perhaps they’re the topics that come up the most in sales conversations.

Put yourself in the shoes of your buyer personas . What types of topics would your target audience search that you’d want your business to get found for?

And You’ve Got the Right Keywords for Your Website SEO

You now have a list of keywords that’ll help you focus on the right topics for your business and get you some short-term and long-term gains.

Be sure to re-evaluate these keywords every few months — once a quarter is a good benchmark, but some businesses like to do it even more often than that.

As you gain even more authority in the SERPs, you’ll find that you can add more and more keywords to your list.

Editor's note: This post was originally published in May 2019 and has been updated for comprehensiveness.

Don't forget to share this post!

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19 Best Free and Paid Keyword Research Tools for SEO

Written by Brian Dean

This is a list of the 19 best keyword research tools in 2024.

These amazing tools have helped my organic traffic grow by 28.55% over the last year:

And in this guide, I’ll reveal the world’s best keyword research tools…

…and help you choose the best one for you.

The best SEO keyword research tools for SEO have one thing in common: helping users boost organic traffic and search engine visibility .

However, each tool approaches this goal differently. Some are all-in-one SEO platforms that specialize in technical SEO, backlink opportunities, and guest post outreach.

Others focus on niche SEO opportunities, such as finding underserved and easy-to-rank keywords or topic cluster research.

We’ve updated this post to account for SEO opportunities in 2024 and guide your choice of the best keyword research tools suitable to your needs.

Editor’s Note : Our recommendation for the top all-in-one SEO tool is Semrush . Keep scrolling for a detailed overview.

19 Best Keyword Research Tools

Semrush works a little differently than the other tools I will show you.

Instead of entering a seed keyword and getting a long list of keyword ideas , Semrush shows you keywords that your competition already ranks for.

(These are usually outside-the-box keywords that would be impossible to find using any other tool.)

Here’s how it works:

First, enter a competitor’s domain name in the field at the top of the page.

If you’re doing SEO in a country outside of the US (for example, in Google.co.uk), you can choose to see information about that specific market. Just choose that country from this menu:

Next, take a look at the “Organic Research” section:

Here’s what the different terms in that section mean:

• Keywords are the estimated number of monthly organic visitors that come from Google.
• Traffic is the estimated number of monthly visitors.
• Traffic Cost indicates how valuable this traffic is (based on Google Ads CPC).

So if you see a domain with a lot of Organic Search Traffic but a low Traffic Cost, you know that they’re ranking for keywords that don’t convert into buyers.

But the real value of Semrush comes from the “Organic Keywords” data:

This box will show you 5 of the top keywords that your competitors are ranking for. To see more, click on “View all [number] organic keywords”.

And you’ll get a list of all of the keywords that the site or URL ranks for:

This page alone will usually give you a handful of solid keywords for digital marketing .

But if you want more ideas, go back to the “Organic Research” overview and check out the “Competitors” in the menu bar.

And you’ll see that site’s first-page competition:

When you click on one of THOSE results, you can see the exact search queries they’re ranking for.

There will be some overlap from what you just saw, but you’ll also (usually) dig up some real gems.

You can also start your Semrush search with a keyword instead of a competitor’s site:

Semrush will show you a “Phrase match report”, which is a list of long-tail keywords that include the keyword you entered:

This is really helpful for finding long-tail variations of Head and Body Keywords.

For example, if you wanted to rank for the keyword “weight loss”, you’ll quickly find that it’s simply too competitive.

But Semrush will show you long-tail variations, like the “weight loss calculator”, that is MUCH easier to rank for:

My Favorite Feature: Keyword Magic

This tool pulls keyword suggestions from Semrush’s massive database of over 25 billion terms.

Semrush is my favorite keyword research tool. Not cheap. But if you’re serious about SEO, it’s a must-have.

2. Free Keyword Tool by Backlinko

For those just starting with SEO, it can be daunting to invest in expensive keyword research tools.

That’s why we’ve created this  free keyword research tool , leveraging the extensive database of keywords from Semrush.

This tool assists in pinpointing low-competition keywords, sparking ideas for blog content, and providing insights into monthly search volumes.

This is our first free tool on Backlinko and I already love using it for quick keyword research.

Scrape suggested keywords from multiple sources. Soovle gives you suggested keyword ideas from Google, YouTube, Bing, Yahoo, Amazon and more.

(All in one place.)

That way, you can find untapped keywords that your competition doesn’t know about.

My Favorite Feature: Saved Suggestions

Easily save your favorite keyword ideas with Soovle’s “drag & drop” saved suggestions feature.

Then, download your favorite keywords to a CSV file.

Soovle is one of the best free keyword research tools out there.

4. TopicRanker 

Discover keywords based on problems and weaknesses on the search engine results page.

TopicRanker is a fantastic tool for those who want to hit the ground running.

It’s meant for the SEO layperson — folks who don’t require advanced SEO features but are on the hunt for keywords that they have an immediate chance of ranking for.

The best part? TopicRanker does all the heavy lifting — all you have to do is input your website URL.

Once the app analyzes the topical depth of your site, it will suggest seed topics relevant to your niche.

Note that these are seed topics — groups of keywords that can be further broken down into related keywords.

Clicking into any of these seed topics is where TopicRanker really starts to shine through by showing you specific keyword queries with multiple problems on the search results page:

The tool combs through millions of search results to find only the search queries with an actual problem with the search results.

It then filters these easy-to-rank keywords ensuring relevancy to your niche by giving you search volume and specific problems it identifies on the search results with actionable ranking strategies.

Expanding ‘view details’ highlights specific problems spotted on the SERP:

• Title mismatch – the title of the page ranking does not contain search query terms
• Thin content – word count of pages ranking is very low,
• Old content – the search results page contains a lot of outdated articles
• Poor readability of the pages ranking high on search results
• Poor load speed of the pages ranking high
• Forums sites such as Quora, Facebook, and LinkedIn appear high on search results
• High spam score for sites appearing high in search results

Take these tips, produce better content, and you’ll start to see results quickly.

TopicRanker takes a unique approach to how it weighs its prioritization metrics, allowing it to surface opportunities other tools won’t find. This tool combines epitomizes efficiency and relevance in keyword research by finding problems and weaknesses in the SERP. TopicRanker will soon be launching its AI Writing Tools to generate content with AI and NLP; making it a must-have for anyone doing SEO. Plus, at just $47 it’s a great value.

Get thousands of related keyword ideas within seconds.

This is a straightforward (yet powerful) tool.

So, what makes Jaaxy unique?

First off, it gives you LOTS of different keyword ideas.

(Including some that you won’t find in most other tools.)

Plus, you get helpful data on every keyword that it generates (including competition, search volume, and potential traffic).

My Favorite Feature: QSR

QSR stands for “Quoted Search Result”.

This is a fancy way of saying: “how many other websites are trying to rank for this exact term?”.

Obviously, the lower this number, the better chance you have of ranking #1.

Jaaxy is a decent freemium tool. Not nearly as good as something like Semrush. But at $50/month, it’s not a bad deal.

6. Google Search Console

Find hundreds of “Opportunity Keywords”.

The Google Search Console isn’t a traditional keyword research tool.

But it does have a feature that makes finding awesome keywords a CINCH.

The feature?

The Performance Report .

This report list out the pages on your site that get the most clicks from Google.

(And the exact keywords that brought them there)

So: how can you use this feature for keyword research?

It’s easy: use it to find “Opportunity Keywords”.

Opportunity Keywords are where you rank between #8-#20 in Google for a specific keyword.

And with little extra on-page SEO , you can find yourself with a nice rankings boost.

For example, my average rankings for the keyword “SEO tool” is 6.2.

That keyword is an Opportunity Keyword. And if I optimize my page around “SEO tool”, my rankings for that term should go up.

My Favorite Feature: Google Analytics + Google Search Console

Did you know that you can combine your Google Search Console and Google Analytics accounts?

Well, you can.

And it’s VERY helpful.

When you do, you’ll get more in-depth keyword data than you would with either tool by itself.

The Google Search Console is an underrated keyword research tool. No other tool can help you find Opportunity Keywords like the GSC.

7. Ahrefs Keywords Explorer

Make smarter keyword decisions.

Ahrefs recently rolled out a new and improved “Keywords Explorer”.

And what I like most about Keywords Explorer is this:

It gives you SUPER in-depth information on each keyword.

Sure, you get the data you’d expect (like search volume). But you also get a breakdown of the first page competition… and how many searchers actually click on a result.

My Favorite Feature: Keyword Difficulty

Most keyword research tools give you vague difficulty info (like “easy” or “difficult”). Or a score (like “89/100”).

But Ahrefs tells you EXACTLY how many backlinks you’ll need to rank on the first page of Google.

Ahrefs is mostly known as for backlink analysis. But I have to say: it’s got a killer keyword research tool. I find myself using it more and more every week.

8. SECockpit

Keyword research for SEO pros.

This a Swiss Army Knife of keyword research tools.

Like any other keyword tool, you give SECockpit a seed keyword… and you get a list of results.

But what makes SECockpit unique is the built-in features that allow you to get A LOT of depth on search trends, organic competition and traffic estimates.

Which means that it’s a tool largely designed for SEO professionals.

Sure, newbies can get value out of this tool. But there’s no doubt that SECockpit is targeted for people that sleep, eat and breathe SEO.

If you’re brand new to SEO, the sheer number of features in this tool might be overwhelming for you. But if you’re looking for lots and lots of depth, you’ll probably get your money’s worth.

With that, here’s how it works.

When you login you’ll automatically go to your Dashboard, where you can create projects around sets of keywords…or jump right in with a single keyword search.

To start the keyword research process, click on “Start a Keyword Search”:

Then, enter a seed keyword in the field marked “Keyword Phrase”:

You can get even more results by choosing to include Google Suggest, Related Searches and synonyms pulled from Google Ads:

When you’re done, click on “save and close” and the tool will get to work:

Here’s the report you’ll get:

If you’ve ever used the Google Keyword Planner , the data here should look familiar to you.

In fact, the columns “Phrase”, “Monthly Searches” and “CPC” are pulled directly from the GKP:

(The only difference is that CPC is called “Top of page bid” in the GKP)

So: what does the other information in SECockpit mean?

Well you’ll notice a bunch of green bars under the column labeled “Niche”:

This bar is a single metric that takes into account first page competition, monthly search volume, and commercial intent. In other words, whether or not that search query is a good overall choice. The larger the bar, the better the keyword.

Next to monthly searches you’ll notice a series of orange bars labeled “Top Results”:

This bar indicates the difficulty of ranking for that particular keyword based on the current top 10 results.

And when you click on a keyword, you get a breakdown of that keyword’s search results.

When you do, SECockpit will display important competition metrics for the top 10 pages in the results… including Moz Domain Authority and total backlinks:

This is a great way to quickly size up competition without having to look one-by-one at the SERPs .

And you go back to the keywords page, you can actually add at least 20 more columns to the results:

For example, you can see a ratio of the keyword’s competition in comparison to its search volume. Or you can get a comparison of the estimated traffic you’ll get from hitting the top 3 for that keyword. And lots more.

My Favorite Feature: Filtering

You can use over 100 filters to find the keywords that you want.

For example, do you only want keywords that get searched for at least 10k times per month? Done.

Or maybe you want terms that have the best ratio of search volume and competition. You got it.

Clunky? Yes. Intuitive? Heck no. Feature-rich? Absolutely. If you want lots of advanced features, and don’t mind a steep learning curve, definitely check out SECockpit.

9. Google Keyword Planner

Tap into Google’s massive keyword database.

The GKP is pretty vanilla compared to most other keyword research tools.

So why use it?

Because the data you get from it comes straight from Google.

(So you know its legit)

My Favorite Feature: “Top of page bid”

This is how much people advertisers are bidding on a keyword.

For example, of you see a top of page bid of $10, people are spending an average of 10 bucks per click.

Obviously, the higher this number, the more commercial intent that searcher has.

The data in the GKP is the most reliable out there. That said, because it’s designed for Google Ads, using it for SEO can be tricky. This Google Keyword Planner Guide shows you how the GKP for SEO-focused keyword research.

10. KeywordTool.io

Get boatloads of targeted keyword ideas.

Here’s another Google Suggest scraper (just like UberSuggest and Soovle).

What makes KeywordTool unique?

Two things:

First, KeywordTool gives you A LOT of keyword suggestions.

For example, I just did a search for “SEO”… and got 1,394 relevant keywords.

Second, you can easily filter, drill-down or expand the results to find the right keywords for you.

My Favorite Feature: Analyze Competitors

This is a very cool feature I don’t see in many other keyword research tools.

Just enter a competitor’s site… and the tool will generate a list of keyword ideas based on that site’s content.

For example, when I pop Backlinko into the tool, I get keywords that I’d expect.

(Like “SEO” and “blog”)

But I also came across terms that I don’t use anywhere on my site… but are closely related to the type of stuff that I write about.

(Like “digital marketing” and “how to check backlinks”)

One of the best overall keyword research tools on the market. Worth a try.

11. Moz Keyword Explorer

Find keywords that will generate the most traffic.

Moz’s Keyword Explorer does an awesome job of finding “lateral” keyword ideas.

For example, take a seed keyword like “weight loss”.

Like most other tools, you get a list of closely related keywords:

But what makes Moz unique is that it’s SMART.

This means you get outside-the-box suggestions that you probably won’t find anywhere else.

My Favorite Feature: “Organic CTR” and “Priority”

These two awesome features let you know how many clicks you can expect to get from your target keyword.

Organic CTR is the number of clicks you can expect to get if you crack the top 10. For example, if a SERP has a ton of PPC ads, news results, and a knowledge graph, your CTR is gonna be low.

Priority takesCTR, search volume and difficulty into account. It’s an “overall” score of whether or not you should target a particular keyword.

So if you’re overwhelmed by keyword data, you can use this single metric to find keywords that are going to bring you the most traffic from Google.

Moz’s keyword tool is pretty darn awesome. Unfortunately, it’s not a standalone tool (you have to pay for their entire suite of SEO tools to use it).

12. Keywords Everywhere

Get search volume (and more) wherever you go.

Keywords Everywhere is a paid keyword research tool that displays keyword data on top of 10 websites …including Ebay, Amazon and Answer The Public.

That way, you don’t need to copy and paste keywords into the Google Keyword Planner. The data shows up in your Chrome browser. Very cool.

My Favorite Feature: “People Also Search For”

Get a list of keywords related to your search term… in the Google search results.

What’s cool about this feature is that you can find keywords that your target customer searches for when they’re not searching for what you sell.

For example, when I search for “SEO Tools”, I see terms like “Google Keyword Planner SEO” and “”Free SEO analysis”.

(Both of which get decent amounts of searches every month)

If you’re serious about keyword research you NEED to install this extension. It rocks.

13. Keyword Snatcher

Find 2,000 keyword ideas with a single search.

If you want a lot – and I mean a lot – of keyword ideas, Keyword Snatcher is a dream come true.

In fact, you’ll usually generate at least 2,000 keywords from a single seed keyword.

Just open up the tool and choose the sources that you want Keyword Snatcher to pull its suggestions from:

I recommend keeping them all checked so you can generate as many keyword ideas as possible.

Next, enter a seed keyword into the field and click “Get Suggestions”:

And after a long wait, you’ll get an insane amount of suggestions:

The big downside of this tool is that it doesn’t give you any data on the keywords that it generates (like search volume and keyword competition). It’s simply a keyword idea tool.

To get that information, you need to extract the list of keywords by clicking on “Download Suggestions” and saving your keyword list as a text or CSV file:

Then, copy and paste those keywords into the Google Keyword Planner.

My Favorite Feature: Word Count

This nifty sorting feature lets you focus on keywords that are a certain length.

(Like terms that are at least 4-words long)

This makes finding long tail keywords MUCH easier.

Not the best keyword tool ever made. But it’s one of the few out there that don’t require a monthly subscription.

14. Google Trends

Find new keywords and search trends.

There are two ways to use Google Trends for keyword research:

First, you can search for a specific keyword…

…and take a look at the “related queries” section.

Second, you can see if whether or not a keyword is growing in popularity.

Why is this important?

Well, let’s say you’re debating between two keywords:

“Content Marketing” and “Inbound Marketing”.

As you can see, interest for “Content Marketing” is growing fast… and fewer people are searching for “Inbound Marketing” than ever before.

This isn’t to say that “Inbound Marketing” is a bad keyword. But the fact that it’s trending down is one factor to keep in mind as you decide on your next keyword.

My Favorite Feature: YouTube Search

See whether a given keyword is growing on the world’s 2nd most popular search engine: YouTube.

If you write lots of evergreen content , you NEED to use Google Trends. That way, you can see if a keyword is going to bring you traffic over the long haul… before you write a word of content.

15. KWFinder

A powerful keyword tool that’s also easy to use. KWFinder is quickly becoming one of my go-to keyword research tools.

Because it has lots of the features that other tools have. But unlike most other tool, KWFinder is VERY intuitive.

As you might expect, this tells you how hard it will be to rank for that keyword.

But unlike most other tools, KWFinder automatically shows a Keyword Difficulty score next to every keyword.

(So there’s no need to click on every single one to see its difficulty score… which gets old fast)

At $29/month you really can’t go wrong with a KWFinder subscription. Great value.

16. QuestionDB

Find lots of question-focused keyword ideas (for free).

QuestionDB pulls question-focused keywords from threads on Reddit.

So if you’re looking for an alternative to Answer The Public, QuestionDB does the job.

My Favorite Feature: Popularity Sort the results by popularity. That way, you can create content that answers these burning questions.

When it comes to finding question-keywords for blog content, QuestionDB can’t be beat.

17. Serpstat

Analyze the first page competition. Serpstat is a SEO software suite with tools for content, link building, and more.

Which means Serpstat doesn’t specialize in keyword research.

Even so, it still has a VERY decent keyword research tool.

My Favorite Feature: Competitors Graph This lets you visualize the sites that are competing for a given keyword (and related terms).

So if you see big bubbles for “Wikipedia” or “Amazon” it’s probably time to look for a different keyword.

Is Serpstat one of best tools on the market? No. But at $19 a month, you get a lot of pro features for your money.

18. AlsoAsked 

AlsoAsked a fantastic tool for topic cluster research.

Seasoned SEOs understand that the best way to rank for head keywords is to create topic clusters — multiple pages that talk about the topic in-depth.

AlsoAsked helps you map out these clusters and visualize how people ask questions on the topic.

For example, let’s say you wanted to rank for ‘home security cameras’ – a head keyword that has a 100,000 monthly search volume.

Plugging this keyword into AlsoAsked gives us four distinct cluster topics, divided into specific questions around each cluster.

Answering these questions in your content is an excellent method of building authoritative topic clusters — and driving tons of SEO traffic.

With API access coming soon on Alsoasked, and with an affordable pricing, it could be a tool for SEO veterans to use while undertaking massive SERP analysis across different niches and regions.

19. KeywordTool

Great app for bulk keyword research.

Rounding up our list is Keyword Tool. It’s a great app for bulk keyword research, although the free plan is somewhat limited.

Plugging a generic keyword into the tool gives you a massive list of keyword suggestions, sorted by search volume, trend, and competition.

Generate lots of relevant keywords by using this tool. However, the tool needs complimentary insights to get the most out of its output. Plus, it integrates data from other search engines besides Google thus opens more ranking opportunities.

So greatfull for this info thanks!

No problem Carlos

There is no better SEO Keyword Research tool other than Google Keyword Planner and Ahrefs. Other give more keywords but they are more effective (according to my keyword research experience).

Thanks Alan. Have you tried SEMRush? It’s also pretty awesome.

How do you feel about mangools?

KWfinder is pretty cool

Mr. Dean I wanted to drop in and personally thank you for everything you do for us rookies in the online marketing field. I have learned so much from your lessons/guides/articles/videos you name it! I also been using Raven Tools and find it pretty helpful as well in regards to keyword research, what say you? Look forward to all your future posts! Also, it says a lot about you that you actually take the time and respond to the comments that users leave you in your articles, don’t really see that too often these days! All the best!

Thanks Daniel. Raven Tools is great, but I haven’t used it for keyword research.

Great stuff Brian! Any recommendations on prioritizing different iterations of keywords within broader keyword themes? Keyword difficulty, search volume etc.

Really good question, Haley. I’d check out this guide that walks you through some of the steps to figuring out the best keywords on a list: http://www.backlinko.com/keyword-research

Brian, thank you for all of these informative guides! I started out as a digital marketing intern and everything that I learned from your site has helped me land a job as a marketing specialist. I’m truly grateful and enjoy everything that you published so far. If you have a chance, I’ve started using this tool called SEOClarity, I was wondering what’s your take on it? Have you used it before or know anyone that has?

Thanks again!

You’re welcome, Nathalie. I actually tried to review SEOClarity a few years ago for my big SEO tools post: https://backlinko.com/seo-tools . I sent them a demo request but never heard from them.

Brian, I´m beyond grateful with this article. It´s really complete and very, very useful, and specially your hint on Google Search Console. I’d like to suggest an article: how to index on Bing? And is it worth it? Thanks!!

Thank you for this fab article! I use Jaaxy (I’m at Wealthy Affiliate, so it comes with the membership), and I like it a lot. However, now that I see you recommend the SEMRush – it will be my next investment in keyword research tools.

Thank you for the amazing info you share with us! Best, Alenka

P.S. Love your YT videos 🙂

You’re welcome, Alenka. Happy to help

SerpStat or Kwfinder (and the mangools suite)? Which one is the better value?

In my opinion, KWFinder

Thanks for the information. Have you tried Wordtracker keyword tool before? What do you think about it?

You’re welcome. I have tried it actually. Solid tool.

Thanks for the very comprehensive keyword tools list.

I am trying to find out anyone tools that can search, generates or suggest alphabetically any keyword *before* the seed (main) keyword.

any keyword + usa (main or seed keyword)

Anyone that I missed?

Again, thanks a lot for your effort 🙂

I think Keywordtool.io does that.

Great list indeed. Which tool do you use often?

Probably SEMRush.

Hey Brian, just to let you know – ‘Suggestion Keyword Finder’ is a non secured site. Personally don’t think non secure websites are value.

Thanks. I’ll check it out.

Thanks for the post. I use Ahrefs myself, but now looking for other tools. Have you tried Windsor keyword optimizer? They have invite-only mode, so looking for the code right now.

You’re welcome, Thomas. I haven’t seen that actually.

Awesome stuff, I’ve tried one or two from the list and settled for Keywords Everywhere Chrome Extension. It works like CHARM for me.

What tool’s Keyword Difficulty would you say is the most accurate? As I understand Ahrefs use a KD score based on the links profile, however that is not always the case. While other tools look more if the keyword is in the title, the number of words of the article etc…

For me, the most important feature is Keyword Difficulty accuracy.

I say most use links to estimate KD. Which tool uses keyword in the title etc?

It’s a great list. I use Keyword Planner and Keyword Everywhere most of the time, I’ll definitely give a try to other tools. Thanks Brian, your content is really helpful for me.

As always great information. Have you tried StoryBase? What do you think about it?

Ubersuggest is also a good tool. I have been using this for a long time. Thanks for this awesome list.

Great list, very helpful. Thank you Brian! Do you happen to know of any free tool for monitoring keywords for your website? Thank you.

You’re welcome, David. I usually use paid tools for that so I’m not 100% of any free ones that work well.

Hi Brian! Thanks for this awesome list… very comprehensive! But I have a question for you… As a small luxury retail business I am of course very keen to get our SEO for the website spot on. My assumption is that one should choose a few options for keyword research and SEO and stick with them. What would be your SEO software bucket list that you would use on a regular basis? Thanks! Nisa

Hi, Brian What about Seobook.com keywords suggestion tool. Is It Good For Researching keywords.

Thanks a lot, this is awesome.

Would also recommend KeyworX if you get chance to look at it ( https://keyworx.org/ )

Not sure if it would factor in your list or not but it’s certainly worth being aware of

Hi, Brian 14 th keyword tool showing 404 error. I am following your guides for a long time thanks for your big knowledge sharing.

Thanks. I’ll replace that ASAP.

is there a tool you recommend for seeing how many words of content the top 10 competitors are using?

I know clearscope does that. I’m surprised it’s not a feature in more tools.

Absolutely great guideline. But each one will not able to pick several tools. So if anyone asks to recommend only one among all, what will be your recommendation?

Hello Brian, We really need a tool that can support every language for a keyword research. More local – based. And even better if that tool, is a freemium one! Do you have any suggestions?

Hi Brian, great piece as usual. I used the Alexa tool for about 3 months. It was steep at $149 a month. Based on your recommendation I cancelled Alexa and subscribed to SEMRush. Is the Alexa tool without merit entirely? Why didn’t you list it? Just curious I geuss. Thanks, Dave

Hey Dave, thank you. I actually haven’t tried the Alexa tool in years. I haven’t really needed to thanks to SEMRush.

Man I’m just eating up your content more and more I read from you. Such an amazing blog.

I’m the owner of a relatively new keyword tool called Keyword Supremacy. We give away free accounts so you can get as many keyword suggestions as you like for free, but getting the search volume, CPC and comp metrics are what cost money.

However, we don’t charge monthly or annually, we sell non-expiring credits as a way to keep our customer VERY happy. Buy some credits, when they are used up, buy some more kind of thing.

We also have a very unique “Local Search” only keyword search that cross references the populations of all towns and cities in USA, Canada & UK. So you can put in a search like “plumber” then choose to see all the cities in “California” with a population of between 50k – 100k and it will spit out plumber suggestions attached to the locale. Pretty neat.

Would I be able to give you a personal tour to make it onto this list possibly?

Informative content Brian Dean. I appreciate the time and energy spent to make this article exist. But I’m still curious! Could you recommend the top three keyword tools in both paid and free versions (3 free & 3 paid). Thanks in advance.

What about Ubersuggest it is good and accurate?

No Long Tail Pro anymore? I know it was in a previous list of yours.

Hi Phil, LTP is solid. But not in my top 15 at the moment.

Hey Brian, really great work, as usual. Just the best :-). I’d like to add another great keyword or better ‘question tool’ called “answerthepublic”. Just google it and check out if it fits. Best regards from Germany, Udo

Thanks Udo. I’m also a big fan of that tool.

Hey Brian, Keywords Everywhere just became a paid chrome extension. Is there a substitute that is free. I simply want to see how many searches per month for a keyword if I check a keyword on google. Very simple.

Hi Eran, I just read that. I plan on updating the post with a new tool. In the meantime, your best bet for figuring out search volume is the Google Keyword Planner.

Hi Brian! Thanks for this awesome list… very comprehensive! But I have a question for you… As a small luxury retail business I am of course very keen to get our SEO for the website spot on. My assumption is that one should choose a few options for keyword research and SEO and stick with them. What would be your SEO software bucket list that you would use on a regular basis? Thanks!

You’re welcome. The thing is, the “best” tools depend on each business, your marketing budget etc. That said, I list my favorites here: https://backlinko.com/seo-tools

Great Article very helpful. What are your views about Longtail Pro? I’d be interested in your opinion.

Have you ever tried Marketing Miner? It has more click-stream data than SEMRush, and Cyrus Shepard uses it on Keyword Research.

Hi Tomas, I haven’t tried Marketing Miner. I have to check it out!

Hi there. What’s your take on Keysearch?

Thanks! Lori

You are not just the backlinko you are also the bosslinko 😀 :*

Again Great post but you missed the https://answerthepublic.com/ It is also one of the best keyword tool.

Great list. I personally use Ahrefs, Google Search Console and Senuto.com

Great list but I can’t believe you left out Ubersuggest which is simply the best free SEO keyword finder tool right now. Or was that intentional…

Thanks. Ubersuggest is great. I’m actually working on a post that dives into how to get the most out of that tool right now.

Wow! Can’t wait to read that post.

Great list…do you think Google Keyword Planner is really that accurate? Search volume of 10-100,000 seems very broad. Hearing many conflicting views on accuracy of this keyword tool for SEO

Heyy Brian, Looking at your blog post has always inspired me to create quality content. Thank you for not being a generic blog post popping up on Google.

No one is better than Ahref and Google Keyword Planner(According to my experience). Ahref is my primary choice if we come on Keyword Research. SEMRush’s Writing assistant is also a good tool. I always use Ahref, Keyword Anywhere to know all the keyword on any particular page and SEMRush.

Thanks, Brian,

I always appreciate your thorough information. It’s very helpful!

I personally use Jaaxy and love it. It gives me everything I need, and many great ideas for future articles.

Cheers, Suzanne

Hey Brian, What do you think about https://answerthepublic.com/ as a KW research tool. – It’s pretty in-depth! All the best, Tom

Thank you Brian, you did a great job but nowadays I am finding it difficult to get to know about keyword difficulty. Although Ahref has some cool features regarding KD, but from my personal experience, I don’t think the data is as much reliable as it should be. I have tried many keyword difficulty tools and ahref estimation is better than other tools but still, it needs improvements. So here my question is, can you please recommend us a way to find out KD of keywords that would be exact and super accurate. I would really appreciate if you can refer us any resource. Keep rocking…

Hi Furqan, the only real way to estimate KD is to publish a page. Every tool calculates KD differently: https://backlinko.com/keyword-research-tool-analysis

Hi Brian, this is some great information. My blog is pretty new so I’ve been learning as I go, but I decided to start with using KeySearch as it was in the ‘budget’ category but seemed to offer some good features. Overall it seems to be decent, and I certainly can’t justify the price tags on SEMrush or AHRefs quite yet, but they look really tempting! What would you recommend to be the next step up from KeySearch that I should aim for as my next upgrade? Thanks! Matt

Thanks Matt. I’d look at SEMRush or Ahrefs next. They both have excellent keyword tools.

Hi there! Thanks for providing such valuable and useful information! These tools seem really useful!

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Keyword Research: An In-Depth Beginner’s Guide

Keyword research is the foundation of search engine optimization. This guide covers what it is and how you should do keyword research.

Keyword research is the foundation of search engine optimization, and without it, you cannot expect to create sustainable and repeatable visibility.

Today, SEO is a much wider discipline than in the early days of the industry and has been segmented into many verticals.

But, at the core, SEO is about finding opportunities online and capturing relevant traffic to a website through visibility in search engines. Keyword research is at the heart of that SEO strategy.

This guide explains what keyword research is, why it’s important, and how you can make a start for a successful SEO strategy.

What Is Keyword Research?

Keyword research is a process of finding words, queries, and phrases that users are searching for, which means a keyword that has search volume.

Research involves connecting the relevance of keywords to a website and its individual pages so that the user can find the best page to answer their query, known as search intent.

Keyword research also involves categorizing search queries into the different stages of a user journey and different categories of search, such as transactional, navigational, and informational.

Good keyword research enables users to find what they need:

• Shoppers who want to buy something can find the right product page.
• A user that wants to know ‘how to’ can find a page that explains a process in-depth.
• Users who want to research a person or brand can find out about that entity.

Keyword research should also carefully consider if ranking on a keyword is worth the effort it would take to rank highly and get visitors. Not all traffic is equal.

Download the ebook, How To Do Keyword Research For SEO .

Why Keyword Research Is Important For SEO

A search engine is an information retrieval system built around the queries that a user inputs to find an answer or relevant information to their search query.

The predominant focus of Google is to connect a user with the best answer to their query and the best website page so that a user is satisfied. Understanding this underlines SEO.

Good keyword research is the foundation of how a business can connect with its potential customers and audience. Understanding this helps to understand a good SEO strategy.

A business strategy starts with understanding its audience and their needs.

• What do they want?
• What do they need?
• What keeps them awake at night?
• What could solve their problem?

Keyword research is an extension of understanding your audience by first considering their needs and then the phrases, keywords, or queries they use to find solutions.

Keyword research is also important for SEO because it can show you where the opportunities are by knowing what your audience is searching for.

This will help you to find new areas of business and to prioritize where to focus attention and resources.

Keyword research will also help you to calculate where you can expect a return on investment to justify your efforts:

• Can a keyword deliver relevant traffic that has the possibility to convert to an end goal?
• What is an estimation of that traffic, and how much is each visitor worth to your business?

Basically, keyword research is the ultimate business research tool.

Read more: Why Keywords Are Still So Very Important For SEO

Keyword Research Basics

Monthly search volume.

Monthly Search Volume (MSV) is a predominant measure of keyword value. It’s a useful metric as a starting point to consider if anyone is searching for that keyword, but it shouldn’t be used in isolation or as the only measure of value.

Just because a keyword has a high MSV doesn’t mean it is the right keyword for you to rank on.

High-volume keywords generally deliver ‘browsing’ traffic at the top of the funnel. They are useful for brand awareness but not for direct conversion.

Low-volume keywords can be much more valuable because they can deliver users who are ready to buy a product.

Read more: A Complete Guide To Keyword Search Volume For SEO

User Intent

User intent refers to what type of result they want to see when they search for a query – the intention of their search.

You will hear user intent talked about a lot in keyword research, as it is one of the most important factors in the process.

User intent is important in two ways, firstly because your primary aim in creating content and pages on a website are to provide a user with information that they want to know.

There’s no point in creating a page about what you care about – your user only cares about their problems and needs.

You can have the best page in the world about the history of cupcakes, but if a user searching for [cupcake] wants a recipe for cupcakes, then they will not click on your link.

Secondly, Google considers relevance when serving results pages (as we said above, they want to deliver the best result for a query). So, the better your page fits user intent, the better it might rank.

Read more: How People Search: Understanding User Intent

When Google considers which pages it will show in search results, the algorithm will look at other pages that users are clicking on for that query.

If we have a query such as [cupcake], Google has to consider if a user wants to know what a cupcake is, how to make a cupcake, or wants to buy a cupcake.

By looking at a search result page, you can get a good idea of user intent from the other results.

Reviewing the search results page of a query should be part of your research process for every keyword you want to consider.

Keyword relevance and user intent are much the same things. It’s about knowing what the user really means when they search. This is more ambiguous for head keywords and less so for long-tail queries.

Long-Tail keywords

Long-tail keywords are called long-tail because they fall to the right of the search demand curve – where the graph looks like a long tail stretching to the right.

The search demand curve is a graph that shows keywords with high volume to the left and lower search volumes to the right.

Longer queries that are more focused fall to the right. Head terms with broad meaning and high volume fall to the left.

The value of long-tail keywords is that they are usually highly focused terms that convert well, as users are actively looking for something very specific.

For example, [iPhone 13] is a head term with high volume (2.7 million MSV), and [Best affordable iPhone 13 cases] (210 MSV) is a long-tail keyword with far fewer searches but would have a high conversion rate.

Long-tail keywords are useful to include in a keyword strategy because they are usually much easier to rank for and achievable for a new website, and the cumulative volume of many long-tail keywords adds up to considerable targeted traffic.

This is a much more stable strategy than focusing on one high-volume ambiguous keyword.

Read more: Long-Tail Keyword Strategy: Why & How To Target Intent For SEO

Types Of Search Query

There are four types of keywords that are useful to understand as they categorize the different user intents and can help when planning a keyword strategy.

• Informational – users looking for information or an answer to a question (top of the funnel).
• Navigational – users wanting to find a specific brand, site, or page (brand searches).
• Commercial – users researching brands, products, or services (middle of the funnel).
• Transactional – users ready to complete a purchase or action (bottom of the funnel).

Local keywords can also be considered another category.

How To Do Keyword Research

Now that you have a better understanding of the basics of keyword research, we can look at where you would start with your research and keyword strategy.

1. How To Find Keyword Ideas

The first stage of keyword research is to brainstorm ideas for seed keywords, and there are several ways to do this.

Your Target Audience

Everything starts with your audience and what they want. Think about their needs, wants, and especially their pain points and problems.

Start to compile your wide list of words, ideas, and topics that surround your niche or business.

Think About Questions

Question-based keyword queries are valuable as they can help you to capture featured snippets and can be a way to jump rank on highly competitive keywords.

Ask your sales team and review CRM data to find the questions that your audience is asking.

Also, think of question modifiers that will start to build out your list:

• What [is a road bike].
• How to [ride a road bike].
• When is [the best time to service a road bike].
• What is [the best road bike].
• Where is [road bike shop].

Current Site Queries

If your site already has some online history, then Google Search Console can tell you what Google thinks your website is relevant for. This is insightful to tell you if your site is conveying the right message and to find opportunities.

If Google is showing a lot of queries that have nothing to do with your product or brand, then you need to apply more keyword focus to your pages.

Look for queries that are position 10 or greater, have reasonable impressions, and you think are relevant to your business.

These are potential quick-win opportunities that you can capture by making improvements and optimizing pages for the query.

Read more: A Complete Google Search Console Guide For SEO Pros

Competitors’ Keywords

Your competitors are a gold mine of information because they might already have invested in extensive research.

A business should be constantly monitoring its competitors anyway, so keep an eye on what content they are producing and the terms they target.

A keyword gap analysis will help you find opportunities your competitors are targeting that you might not have considered.

Read more: Competitor Keyword Analysis: 5 Ways To Fill The Gaps In Your Organic Strategy & Get More Traffic

Seed Keywords

Start with high-level ‘seed’ keywords that you can use as a starting point to then open up variants and related queries.

Seed keywords are ‘big’ head terms such as [iPhone], [trainers], [road bike], or [cupcake].

For each seed keyword, start to think of topics that are related:

• Road bike maintenance.
• Road bike training.
• Road bike clothing.
• Road bike lights.

Also, use question modifiers and buying modifiers such as:

• Best [road bike].
• Buy [road bike].
• Price [for women’s road bike].
• [road bikes for hire] near me.
• Reviews [of road bikes under $1,000].

When you have finished this process, you should have a raw list of potential keywords grouped in topics – such as maintenance, clothing, training, etc.

2. How To Analyze Keywords

Once you have your raw list, it’s time to start to analyze and sort by value and opportunity.

Search Volume

Search volume will tell you if anyone is actively searching for this term.

For a first-stage strategy, you should aim for keywords with a mid-range and long-tail volume for quick wins and then build up to approach more competitive terms with higher volumes.

Head keywords with super high volumes (like ‘iPhone’) are not the best keywords to focus on as they can be too ambiguous and rarely have a specific intent.

Also, the amount of work that is needed to rank can be too high a barrier for entry unless you have an established domain of significant authority.

If a tool shows a keyword with zero search volume, this doesn’t always mean you should discard the term.

If the keyword is shown in the tool, then there can be value to consider targeting it in your strategy. However, make sure you know your audience and what is relevant to them before you invest resources in a zero-volume keyword.

Read more: Why You Should Target Zero Search Volume Keywords

Search Intent

After you have sorted your raw lists by search volumes, it’s then time to review the intent for each keyword that you would like to target.

The SERP will tell you everything that you need to know, and you should always review SERPs for clues on how to construct content and rank.

Look at the other listing that rank highly:

• Are they ‘how-to’ guides that indicate it’s informational?
• Do the titles say ‘buy,’ ‘best,’ or include product names?
• Is there a shopping carousel that indicates a buying keyword?
• Is there a location map that indicates it’s a local search?

Tag each keyword type and then consider which are the strongest keywords from each group.

You can also use a research tool that will tell you the type of keyword.

Topic Clusters

Grouping keywords into topic clusters is an advanced keyword strategy that can help to strengthen the topic authority of a site.

To do this, you would start with a high-volume head keyword and then research a series of keywords that supports that head term.

After creating pages of content that target each keyword, you use internal linking to connect pages with the same topic.

Read more: Keyword Clusters: How To Level Up Your SEO Content Strategy

3. How To Choose Organic Keywords

After sorting the volumes, intent, and topics, you will need to decide if you have a chance of ranking on a term by looking at how much competition there is for each keyword.

Keyword Difficulty

Keyword difficulty is one of the most important keyword metrics when doing your research.

If a keyword is so competitive that you need hundreds of thousands of dollars to rank, then you need to get strategic.

The easiest way to calculate keyword difficulty is to use a research tool that gives a score for each keyword.

Or, you can refer to Google Keyword Planner Tool and look at the CPC and level of difficulty. The higher the CPC bid, the higher the competition.

If you are starting out, first approach the lower competition keywords that are achievable and then build your way up to more competitive terms.

Read more: Why Keyword Research Is Useful For SEO & How To Rank

Connecting To Your Objectives And Goals

Unless a keyword can actually deliver a result for you – do you want to target it?

As we said above, targeting head terms is not the best strategy as they will, at best, deliver browsing or drive-by visitors. Unless you are a big brand with a big budget that is aiming for brand awareness, this is not the best application of your resources and budget.

Choosing your keyword priority should start with what can give you the best return in the shortest time frame.

Good keyword research is not just about trying to target a high-volume popular keyword. A good keyword strategy is about finding the right keywords for your needs and outcome. Always keep that front and center.

Read more: How To Calculate ROI For SEO When Targeting A Set Of Keywords

Watch John Mueller talk about ranking for head keywords in this video from the 38:55 minute mark.

Using Keyword Research Tools

Doing your research without a tool is limited; for the most in-depth keyword research, you need help to find keyword opportunities you had not thought of.

The following keyword research tools are all free versions that you can start out with.

Google Keyword Planner

The original keyword tool has evolved over the years, but it still remains one of the best free keyword tools and a good starting point to find seed keywords and keyword ideas.

The Google tool is aligned with Google Ads, so the data is skewed towards paid ads but is still valuable for research.

You need a Google Ads account to access the tool. Google will try to force you to set up an active campaign, but you can access the account by setting up an account without a campaign.

Without a campaign running, you will only get limited search volumes displayed in ranges, but the tool is still useful for its suggestions of keyword ideas. If you have an active campaign, Google will show you the monthly search volume.

You can add up to 10 seed keywords and get a list of suggested keywords, and run competitor URLs in the tool to find keywords they are targeting. Doing this is a great place to start building out raw lists of keywords to work from.

Read more: How To Use Google Keyword Planner

Read more: 9 Creative Ways To Use Google’s Keyword Planner Tool

Google Trends

Google Trends offers data based on actual search query data. It doesn’t provide search volumes, but the data in Google trends can be compared with actual search volumes from other tools so you can get a comparative feel of what the actual volumes are.

Where Trends excels is to identify trending topics and subtopics in a niche and to find geographic search trends in a local area. Trends will recommend related keywords that are currently growing in popularity.

As part of a keyword strategy, this can show you where to focus resources and when to stop investing in terms.

Read more: How To Use Google Trends For SEO

Google Autocomplete

Previously known as Suggest, Autocomplete is integrated into the Google search box to help users complete their search with what Google calls ‘predictions.’

Google takes its predictions from common searches and trending searches.

As the suggestions are all variations around the topic you are typing, the results shown give you an insight into other related terms that users could be looking for.

Checking the predictions that Google provides in Autocomplete can help you find more variations and keywords to consider.

Read more: Google Autocomplete: A Complete SEO Guide

Answer The Public

Answer The Public is a powerful tool that scrapes data from Google Autocomplete and connects a seed keyword with a variety of modifiers to produce a list of variants.

Answer The Public will quickly provide a list of suggestions, especially based on questions that you can use as a raw list to then review.

Read more: More Free Keyword Research Tools

Paid Keyword Research Tools

Free keyword tools are great to get you started and to create raw lists of keywords that you can then drill into.

However, for the best results, you might want to invest in a paid competitive analysis tool that can help you get monthly search volume and keyword difficulty data.

Some tools will also help with assigning topics and clustering for more advanced keyword strategies.

Anyone who does keyword research in-depth or to an advanced level will have their own process. They will also use a variety of tools and a combination of paid and free resources to get the best results.

Read more: Best Keyword Research Tools

Advanced Keyword Strategies

Now that you have an understanding of how to get started with keyword research, experiment with a few different websites and niches. Doing the work yourself is the best way to learn.

Once you have a better understanding in practice, move into more advanced methods and strategies to take your keyword research to the next level.

Advanced Keyword Research

• B2B Keyword Research Done Right With Practical Examples
• Keyword Clusters: How To Level Up Your SEO Content Strategy
• Building A Keyword Strategy For Comparison Content

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Shelley Walsh is the SEO Content Strategist at SEJ & produces the Pioneers, a series about the history of SEO ...

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• Open access
• Published: 05 April 2024

The impact of health insurance on maternal and reproductive health service utilization and financial protection in low- and lower middle-income countries: a systematic review of the evidence

• Joseph Kazibwe 1 ,
• Phuong Bich Tran 2 ,
• Andrea Hannah Kaiser 1 ,
• Simon Peter Kasagga 3 ,
• Felix Masiye 4 ,
• Björn Ekman 1 &
• Jesper Sundewall 1 , 5  

BMC Health Services Research volume  24 , Article number:  432 ( 2024 ) Cite this article

428 Accesses

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Low- and middle-income countries have committed to achieving universal health coverage (UHC) as a means to enhance access to services and improve financial protection. One of the key health financing reforms to achieve UHC is the introduction or expansion of health insurance to enhance access to basic health services, including maternal and reproductive health care. However, there is a paucity of evidence of the extent to which these reforms have had impact on the main policy objectives of enhancing service utilization and financial protection. The aim of this systematic review is to assess the existing evidence on the causal impact of health insurance on maternal and reproductive health service utilization and financial protection in low- and lower middle-income countries.

The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search included six databases: Medline, Embase, Web of Science, Cochrane, CINAHL, and Scopus as of 23rd May 2023. The keywords included health insurance, impact, utilisation, financial protection, and maternal and reproductive health. The search was followed by independent title and abstract screening and full text review by two reviewers using the Covidence software. Studies published in English since 2010, which reported on the impact of health insurance on maternal and reproductive health utilisation and or financial protection were included in the review. The ROBINS-I tool was used to assess the quality of the included studies.

A total of 17 studies fulfilled the inclusion criteria. The majority of the studies (82.4%, n  = 14) were nationally representative. Most studies found that health insurance had a significant positive impact on having at least four antenatal care (ANC) visits, delivery at a health facility and having a delivery assisted by a skilled attendant with average treatment effects ranging from 0.02 to 0.11, 0.03 to 0.34 and 0.03 to 0.23 respectively. There was no evidence that health insurance had increased postnatal care, access to contraception and financial protection for maternal and reproductive health services. Various maternal and reproductive health indicators were reported in studies. ANC had the greatest number of reported indicators ( n  = 10), followed by financial protection ( n  = 6), postnatal care ( n  = 5), and delivery care ( n  = 4). The overall quality of the evidence was moderate based on the risk of bias assessment.

The introduction or expansion of various types of health insurance can be a useful intervention to improve ANC (receiving at least four ANC visits) and delivery care (delivery at health facility and delivery assisted by skilled birth attendant) service utilization in low- and lower-middle-income countries. Implementation of health insurance could enable countries’ progress towards UHC and reduce maternal mortality. However, more research using rigorous impact evaluation methods is needed to investigate the causal impact of health insurance coverage on postnatal care utilization, contraceptive use and financial protection both in the general population and by socioeconomic status.

Trial registration

This study was registered with Prospero (CRD42021285776).

Peer Review reports

Introduction

Low- and middle-income countries (LMICs) have committed to making progress towards universal health coverage (UHC) as part of the Sustainable Development Goals (SDGs). UHC has been defined by the World Health Organization (WHO) as a state where all people and communities receive the quality health services they need, when they need them, without experiencing financial hardship due to health care costs [ 1 ]. Generally, high income countries have attained high levels of service coverage (UHC service coverage index of at least 80 out of 100), however a majority of low- and lower-middle income countries (LLMICs) are still lagging behind (UHC service coverage index of less than 60 out of 100) as of 2022 [ 2 ]. The health service coverage index is the average coverage of essential services based on 14 tracer indicators of health service coverage (encompassing reproductive, maternal, newborn and child health, infectious diseases, non-communicable diseases and service capacity and access) among the general and the most disadvantaged population [ 3 , 4 ]. Similarly, while efforts have been made to decrease catastrophic health expenditure globally, LLMICs continue to face the greatest burden of people being thrust into extreme poverty (spending less than international dollars 1.9 per day) due to out of pocket payments (OOP) on healthcare [ 5 ].

In order to advance towards UHC, several countries especially LLMICs, are planning or implementing health financing reforms with a view to introduce or expand some form of health insurance (i.e. prepayment and pooling of funds). Countries that have opted for health insurance schemes – specifically social health insurance (SHI) – have seen an increment in their health expenditure compared to those that have a tax-based model of financing [ 6 , 7 ]. However, the choice of health financing mechanism does not necessarily have a clear effect on health outcomes (such as increased immunization coverage, reduced under-five mortality) or financial protection [ 7 ]. For example, Wagstaff who looked at Organization for Economic Co-operation and Development (OECD) countries found that neither a tax-funded health system nor a SHI system had a significant effect on health outcomes [ 6 ] while Gabani et al. who looked at over 124 countries found that transitions from predominantly OOP financing to tax-funded health systems yielded significantly better health outcomes than transitions from predominantly OOP financing to health insurance [ 7 ].

An increasing number of LLMICs have started implementing, or are planning to implement health insurance reforms to advance UHC [ 8 , 9 , 10 ]. Health insurance can go by different names including SHI, publicly funded health insurance (PFHI), community-based health insurance (CBHI) and private for-profit health insurance based on the pre-payment arrangement within an insurance scheme [ 11 ]. The intention, however, is the same for all health insurance systems (especially not for profit health insurance), which is to pool the risk of high-cost health care across a large number of people in order to protect individuals from high unexpected medical costs. Through a system of prepayment for guaranteed access to a predetermined package of health benefits, individuals can benefit from more predictable health care expenses and be protected from catastrophic health expenditure. A number of countries are opting for SHI. SHI refers to a health insurance system where contributions in form of premiums are collected from employees, employers and or government and pooled into an insurance fund [ 12 ]. Over time, SHI has been defined to mean insurance schemes where employees and employers both contribute premiums to the insurance fund. In instances where contributions/premiums are paid by government, such insurance has been referred to as PFHI for example in India [ 13 , 14 ]. PFHI has been implemented in some LLMIC settings, where there is a large informal sector, and inability to pay or collect premiums. In some cases, a health insurance scheme can be a combination of tiered contributions by members and subsidies from the government for example contributory and non-contributory.

A core component of UHC is maternal and reproductive health services (MRH), which has received a lot of attention in the past few decades. It was central to the Millennium Development Goals, specifically Goal 5 aimed at improving maternal health [ 15 ]; and it is currently well stipulated within the SDGs. MRH is one of the four categories measured for the UHC service coverage index. The other health services areas under the index are infectious diseases, non-communicable diseases and service capacity and access [ 16 ]. Several interventions have been implemented to improve MRH, including sexual and reproductive health and rights interventions. These endeavors have led to the improvement of MRH globally [ 17 ]. However, several LLMICs continue to face high maternal mortality ratios (accounting for 94% of all maternal deaths globally) [ 18 ], which is far from achieving the target of reducing maternal mortality to 70 deaths per 100,000 live births. Furthermore, women have continued to experience financial barriers when seeking healthcare, and they are found to be more vulnerable to facing financial hardships when accessing care, compared to men [ 19 ].

Despite the increasing interest surrounding health insurance, our understanding of the actual causal impact of the implemented reforms remains limited. Several reviews have examined the existing evidence on the impact of health insurance on service utilization and financial protection, but the results are inconclusive [ 20 , 21 , 22 , 23 ]. A review by Comfort et al. [ 24 ] analyzed the effects of health insurance on maternal health services in LMICs. Insurance (a mix of different types of insurance) was found to be consistently associated with increased utilization of facility-based child delivery and delivery assisted by a skilled health worker.

However, Comfort et al.’s study did not address the impact of health insurance on financial protection. In addition, the study examined various types of insurance schemes, including a mix of both for-profit and not-for-profit models. The study also included conditional cash transfers (or CCTs, a kind of demand-side financing). Therefore, based on Comfort et al.'s findings, it can be challenging to discern the specific impact of individual types of insurance. Our study differs from that of Comfort et al. as we specifically focus on well-specified not-for-profit health insurance as the intervention in LLMICs. Furthermore, we have also examined and reported on the impact of insurance on the financial protection of women of reproductive age. Our review constitutes a contribution to the current evidence base on this topic as no previous review has specifically examined the impact of not-for-profit health insurance on maternal and reproductive service utilization and financial protection in LLMICs, despite the recognition that MRH is among the four core categories of essential health services under UHC [ 4 ].

Our study aims to review the existing evidence of the causal impact of health insurance on maternal and reproductive service utilization and financial protection in LLMICs to inform ongoing health financing reform discussions and identify evidence gaps for future research.

The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines [ 25 ]. In addition, we used the PICO framework [ 26 ] to guide the study scope. The study is registered with PROSPERO, registration number CRD42021285776. We searched electronic databases to identify published articles, and bibliographies of included articles were screened to identify missed articles that fulfilled the inclusion criteria.

To narrow the scope of our study, we employed the PICO framework with the following parameters – Population: Women of reproductive age residing in low- and lower middle-income countries as classified by the World Bank [ 27 ] as of 1st July 2021 – Intervention: health insurance – Comparator: uninsured women – Outcomes: two types of outcomes were considered, i) utilisation of maternal and reproductive health services, and ii) financial protection. Outcomes on utilisation of MRH included contraceptive use, number of antenatal care (ANC) visits, delivery at health facility. Outcomes on financial protection included catastrophic health expenditure and impoverishment impact of out-of-pocket expenditure (OOPE).”

Studies reporting impact

In this study, we reviewed studies that reported impact, i.e. studies that employed a research design enabling the identification of a causal effect of the intervention on an outcome of relevance. We defined studies that report impact as studies that estimate the causal influence the intervention (health insurance) has on a given outcome (MRH and financial protection indicators).

Intervention

The intervention in this study is any not-for-profit health insurance. Health insurance is the protection of registered members (beneficiaries) from high costs of/expenditure on health services by pooling resources through payment of agreed periodic premiums. A person or entity (employer or government) pays a periodic premium to enable them access to health services without requiring them to pay for the services. In some cases where there is a co-payment, the beneficiary pays a small amount or portion of the cost of services they receive. This arrangement aims at sharing the financial risks associated with falling ill and needing medical care.

Inclusion criteria

Our review applied the following inclusion criteria. We included articles that:

Reported on any specific type of not-for-profit health insurance. The reason was to focus on health insurance implemented with the intention of progressing towards UHC.

Reported on the impact of health insurance on MRH service utilization and/or financial protection of people accessing MRH services, and where any MRH service is included in the health benefit package of the insurance scheme. MRH in this study covers contraception, pre- and postnatal services, and delivery care.

Used experimental and/or quasi experimental study designs.

Were published from 2010 onwards and in English. We included studies from 2010 to capture the most recent evidence, as insurance schemes undergo reforms over time with likely implications on their respective performance. Relevant unpublished studies in the form of reports were also considered.

Exclusion criteria

Articles were excluded if they:

Reported on the impact of private for-profit insurance only or aggregated all types of insurance (both for-profit and not-for-profit) as one. Excluding such articles was necessary because grouping different insurance types as a single intervention makes it challenging to differentiate the specific impact of each insurance type.

Adopted a non-experimental study design prohibiting the identification of a causal effect.

Reported on the impact of health insurance qualitatively.

Were published in languages other than English.

Had unavailable full texts.

Databases searched

We searched for published literature in selected electronic databases and bibliographies. Databases included Medline (PubMed), Embase, Web of Science, CINAHL, Cochrane and Scopus. Additionally, we reviewed bibliographies of included articles to find other relevant articles that might have been missed in the search. It should be noted that although no time restrictions were included in the search strategy, studies published before 2010 were excluded at the screening stage.

Search strategy

The six electronic databases were searched on the 31st of October 2021, with an update of the search carried out on 23rd May 2023. The search strategy included all keywords and respective keyword variations for the five keyword domains: health insurance, impact, utilisation, financial protection, and maternal and reproductive health. Search strategies were customised for the respective databases (Supplementary Material 1 : Appendix 1).

Study selection

The PRISMA guidelines [ 28 ] were followed in the articles screening and selection process. The articles retrieved from the search were uploaded to Covidence systematic review software [ 29 ], where duplicates were removed. Initially, at least two independent researchers (PT, SPK, and JK) carried out screening for each title and abstract. Subsequently, full text screening was conducted by PT and JK, following a standard protocol. In the event of any conflict, a fourth researcher (JS) was available to review the conflict and make the final decision.

Data extraction

We developed a data extraction template in Microsoft Excel, which was piloted on ten randomly selected articles and necessary adjustments were made. We extracted data on author, year of publication, target group, study design, country, geographic location, setting (rural/urban/mixed), level of health facility, study participants, type of insurance, year of implementation of insurance, source of data, year of data collection, analysis methods used, description of the insurance, type of membership (voluntary/compulsory), enrolment requirements, services covered by insurance, services received, insurance coverage, premium, reimbursement rates, co-payments, OOPE, indicators used in measuring utilisation, financial protection and their definitions, proportion of households experiencing catastrophic heath expenditure (CHE), measures used for impact, theoretical framework used, reported impact (adjusted and unadjusted), and correction of self-selection among others.

Quality assessment and risk of bias in individual studies

The quality of the evidence was assessed through a two-step process, including: 1) using a tool for assessing the risk of bias in each study and 2) using the GRADE criteria to determine the level of certainty of the evidence.

The study design of an article being assessed determined the quality assessment tool to be used. Since we did not find any randomised studies, we resorted to a tool suitable for non-randomised studies. We used the Risk of Bias in Non-randomised Studies of Interventions (ROBINS-I) tool developed by the Development and Evaluation (GRADE) working group [ 30 ]. The tool rates the risk of bias in seven domains, 1) Bias due to confounding, 2) Bias in selection of participants into the study, 3) Bias in classification of interventions, 4) Bias due to departures from intended interventions, 5) Bias due to missing data, 6) Bias in measurement of outcomes, and 7) Bias in selection of reported results [ 31 ]. The study can be rated as low risk of bias, moderate risk of bias, or serious risk of bias based on the respective guiding questions in the tool for each domain. The overall extent of bias of a study is determined by the respective domain ratings, following the algorithm in the guide. The above tool was selected following the findings of a systematic review by Ma et al [ 32 ], describing the ROBINS-I tool as one of the most reliable tools available for quality assessment.

The certainty level of evidence of each study was then determined following the GRADE criteria based on the ROBINS-I tool [ 33 ]. It involved three steps: 1) establishing the initial level of certainty as advised by GRADE, 2) considering lowering or raising the level of certainty and 3) determining the final certainty rating. The certainty level of the evidence could be high, moderate, low, or very low depending on the rating. A non-randomised study’s evidence is initially rated as high level of certainty, which is then downgraded by a level or two depending on how it performs in the following domains: limitations in the detailed study design and execution; inconsistency (or heterogeneity); indirectness (PICO and applicability); imprecision; and publication bias. The downgrade of the certainty level of the evidence is mitigated (increased) by the magnitude of the effect estimates.

Reporting, summary measures and synthesis of results

The reporting was both descriptive and analytical. For extracted quantitative data, we reported summary measures. Indicators reported by the different studies were categorised into MRH service utilisation indicators and financial protection indicators with several subcategories each. Additionally, we elicited the covariates used in the adjustment of results from the studies and categorised these into characteristics including mother’s demographic, households, partners, communities, and mother’s perceptions. The reported impact of the insurance on MRH service utilisation and financial protection was summarised in five groups: positive and significant impact, positive and not significant impact, no impact, negative and not significant impact, and negative and significant impact. The impact findings were summarised in a table showing the proportion of studies that reported a positive significant impact for each respective indicator. Studies that had a high risk of bias were excluded in the calculation of the proportions as shown in Table 3 .

The systematic literature search yielded a total of 11,988 studies after deduplication. Following title and abstract screening and full text review, we included 17 studies that fulfilled our eligibility criteria. Figure 1 shows the flow of selection process including reasons for exclusion of articles at the full text reading stage.

PRISMA flow chart

Characteristics of included studies

Table 1 provides an overview of key characteristics of the included studies.

All the included studies were quasi experimental studies ( n  = 17). Quasi experimental studies are non-randomised studies that evaluate an intervention with the aim of demonstrating causality between the intervention and outcome [ 51 ]. Ghana and Indonesia had the most studies with three each. These were followed by the Philippines ( n  = 2), and Mauritania ( n  = 2). The review included one study from each of the following countries: Tanzania, Egypt, Rwanda, Ethiopia, India, and Senegal (Table 1 ). Additionally, there was a multi-country study that encompassed three countries: Ghana, Rwanda, and Indonesia [ 46 ]. Most studies ( n  = 14) were nationally representative of the population, while the remaining three were carried out in specific region(s) within the specified country [ 42 , 48 , 49 ]. Three studies were specifically conducted in rural settings [ 42 , 48 , 49 ], and no studies focused on urban settings exclusively. The rest of the studies ( n  = 14) covered both rural and urban areas. All the studies included in the review involved female participants of childbearing age from 15 years old. The majority of the studies ( n  = 13) specifically focused on women aged between 15 and 49. The studies focused on three types of health insurance, including social health insurance (e.g. Ghana), community-based health insurance (e.g. Rwanda), and publicly-funded health insurance (e.g. India). The data sources used were mostly secondary data ( n  = 14), specifically demographic health survey (DHS) data [ 52 ], Multiple Indicator Cluster Survey (MICS) and Family Life Survey (FLS).

Quality assessment of included studies

The overall quality of assessed studies was rated as moderate. A total of 12 studies were rated as having a high level of certainty of evidence [ 36 , 37 , 38 , 39 , 41 , 43 , 44 , 45 , 46 , 48 , 49 , 50 ], two studies had moderate while those rated low and very low were two [ 40 , 42 ] and one [ 34 ], respectively. This assessment was based on the categorization of the risk of bias using the ROBINS-I tool. Overall, the majority of the studies ( n  = 15; 88.2%) were categorised as having moderate risk of bias, and two studies were rated as having serious risk [ 34 , 42 ]. No study was found with an overall low risk of bias. All studies were rated as low risk of bias in three domains: bias in classification of interventions, bias due to departures from intended interventions, and bias due to missing data as shown in Fig. 2 . For the domain of bias in selection of reported results, the majority of the studies ( n  = 16, 94.1%) were rated as low risk of bias, while the rest ( n  = 1, 5.9%) was rated as moderate risk [ 40 ]. One study showed serious risk of bias due to confounding [ 34 ], and one [ 42 ] study was assessed to have serious risk of bias in the measurement of outcomes. The table with the assessment results is included in Supplementary Material 1 : Appendix 2, and Fig. 2 shows the ratings by domain as well as the overall rating of bias.

Assessment of the risk of bias of the studies according to the seven domains, using the ROBINS-I tool

Indicators used to measure the impact

Table 2 shows the indicators used to measure the impact of health insurance on MRH service utilisation and financial protection. There was a large variation in the number of indicators per category of MRH services, and the frequency to which they were reported in the studies. Regarding the number of indicators per category, ANC had the greatest number of reported indicators ( n  = 10), followed by financial protection ( n  = 6), postnatal care ( n  = 5), and delivery care ( n  = 4). Contraception had only one indicator, with three studies reporting on this indicator [ 34 , 40 , 42 ]. Regarding the frequency of use of the indicators, under the ANC category, the most common indicator was having at least four ANC visits during pregnancy ( n  = 9, 52.9%), which was also the second most reported MRH indicator in this review. For delivery care, delivery at a health facility was the most reported indicator in the delivery care category (and the most reported indicator in this review) ( n  = 14, 82.4%); followed by delivery by skilled attendant ( n  = 7, 41.2%). For the postnatal care category, having postnatal care (without specifying the point or time of access) was the most common indicator used in this category ( n  = 4, 23.5%) [ 38 , 40 , 41 , 45 ]. For financial protection, six indicators were reported. OOPE on delivery services was reported in four studies (23.5%) [ 34 , 42 , 43 , 50 ]. OOPE due to ANC, OOPE due to C-section, financial distress after C-section, and CHE were each reported in one study. Financial distress was defined by Garg et al. as a situation where a patient, or their household member, borrowed money or sold their assets to cover the OOPE due to seeking maternal health care [ 50 ].

Impact of health insurance on MRH service utilisation and financial protection

Studies reported a positive effect of the health insurances on ANC and delivery care indicators, with a clear significant positive impact reported for the most used indicators (having at least four ANC visits, delivery at a health facility, and delivery assisted by a skilled attendant) as shown in Table 3 . Specifically, 85.7% of the studies found a significant positive impact between health insurance and delivery with assistance from a skilled attendant, 83.3% reported a significant positive impact on delivery at a health facility, and 75.0% indicated a significant positive impact on having at least four ANC visits during pregnancy. In contrast, the evidence on the impact of health insurance on contraceptive use [ 40 ], postnatal care [ 36 , 38 , 40 , 41 , 45 ] and financial protection [ 43 , 48 , 50 ] indicators was scanty, variable and inconclusive.

Certain indicators (ANC at health facility, postnatal care visit at health facility in less than 2 months after delivery, OOPE due to ANC, and OOPE due to PNC) were not included in the analysis, because these indicators were only reported in articles that were excluded due to their serious risk of bias.

Table 4 shows the magnitude of the impact reported by each study for indicators that were reported by more than one study.

ANC: Health insurance increased the chance of a pregnant woman having at least four ANC visits. The magnitude of the positive significant impact of health insurance on receiving at least four ANC visits during a pregnancy ranged between approximately 2% [ 46 ] and 11% [ 36 ]. Insurance increased the total number of ANC visits during pregnancy. The magnitude of positive significant impact of health insurance on the number of ANC during pregnancy ranged from 43% [ 47 ] to 56% [ 48 ]. On the other hand, insurance did not have a significant positive impact on having an ANC visit in the first trimester except for Indonesia [ 46 ].

Delivery care: Health insurance increased chances of having a delivery at a health facility and delivery by a skilled attendant. Studies that reported a significant positive impact of health insurance on delivery at a health facility found a magnitude ranging from approximately 3% [ 38 ] to 34% [ 48 ]. The magnitude of the impact ranged from 3% [ 41 ] to 23% [ 45 ] for having a delivery assisted by a skilled attendant.

Postnatal care: Health insurance showed an increase in the chance of receiving postnatal care but only 50% of the studies reporting on the impact of health insurance on postnatal reported a significant positive increase. The magnitude of the health insurance on postnatal care among studies that reported positive significant impact was 4% [ 41 ] and 9% [ 45 ].

Reduction of OOPE: Evidence suggests that health insurance has generally reduced OOP payments for MRH services. However, of the two studies that reported on OOPE only one found a significant reduction in OOPE of 1,136,966 Indonesian Rupiah (IDR) and 676,402 IDR for non-contributory and contributory health insurance in Indonesia respectively [ 43 ].

Methods used to estimate the impact of health insurance on MRH service utilisation

No study used randomisation in allocating participants to the intervention or control groups.

A wide range of statistical methods were applied in the studies (Table 5 ). Propensity Score Analysis/Matching (PSM) was the most used statistical methods (58.8%), followed by difference-in-difference (DID) analysis (11.8%). Some studies utilised more than one method; for example, Samarakoon et al [ 34 ] used both PSM and DID. The effect measures used were mostly Average Treatment Effect (ATE) (47.1%), and Average Treatment Effect on the Treated (ATT) (35.3%).

Several methods were used to adjust for self-selection, such as PSM, DID, conditional mixed process framework (CMP) (e.g. Agbanyo et al [ 35 ]), entropy balance weighting of observed characteristics (e.g. Aizawa [ 43 ]) and coarsened exact matching (CEM) methods (e.g. Chang et al [ 37 ]). Anindya et al [ 41 ] used more than one method, specifically PSM followed by CEM for sensitivity analysis and robustness check.

Covariates adjusted for in the studies

Table 5 presents the covariates that were adjusted for in the studies. Overall, the most used covariates were age, the education level of the woman, and wealth status of the household; with each being used in 76.5% of all studies. This was followed by place of residence (rural/urban) and marital status, with each at 58.8%. The other covariates were used in less than 50% of the studies that adjusted for covariates.

Our review shows that there is considerable evidence on the impact of health insurance on ANC and delivery care service utilisation. However, there is a scarcity of evidence on the impact of health insurance on the financial protection of women seeking MRH services, utilisation of postnatal care, and contraception. We found that health insurance has a significant positive impact on ANC and delivery care service utilisation specifically having at least four ANC visits, delivery at a health facility and having a delivery assisted by a skilled attendant. However, findings regarding its impact on financial protection, contraception, and postnatal care were inconclusive.

ANC and delivery care utilisation

Among the articles reviewed, recent evidence shows that health insurance generally exhibits a positive impact on ANC and delivery care service utilisation. This is in line with the findings of Spaan et al. and Erlangga et al. reporting that social health insurance and CBHI improved general health service utilisation [ 20 , 21 ]. With comparison to Acharya et al [ 22 ] – who reported inconclusive results on the impact of health insurance on general health service utilisation among the informal sector – the evidence that was reported on MRH service utilisation in that study concurs with our findings.

On the other hand, our findings differ from Comfort et al., who stated that there was no evidence that insurance increased maternal health service utilisation [ 24 ]. The statement was premised on the fact that Comfort et al. did not identify any studies that used randomised methods. Comfort et al. argued that causality could not be established without randomisation of the intervention. However, quasi experimental studies can estimate causation which are the only studies we included in our review. In addition, as shown in Table 1 , all the studies included in our review were published after the publication of Comfort et al.’s review (2013). This indicates that studies which estimated the causal relationship between health insurance and MRH are recent.

For countries that are still experiencing high MMR [ 53 , 54 ], the evidence available on the positive impact of health insurance on at least four ANC visits, delivery at a health facility and having a delivery assisted by a skilled attendant can inform the country’s health financing reforms, encourage implementation, and expansion of such insurance schemes as an intervention to increase access to care and reduce MMR. MRH services such as attending ANC and having a health facility-based delivery have been highlighted as some of the ways to counter occurrence of maternal mortality[ 54 ], and investment in these services was found to be cost-effective [ 17 , 55 ].

Limited evidence on financial protection when accessing MRH

The available evidence suggests that health insurance plays a role in reducing OOPE. However, it is important to note that the evidence in this area is weak, with only a limited number of studies reporting on OOPE indicators. The findings are variable and inconclusive, particularly regarding the likelihood of CHE and the reduction of OOPE specifically related to delivery care. This finding contrasts with the results of a previous systematic review examining financial protection in a broader context [ 20 ]. Health insurance is known to reduce CHE generally. However, we did not find any evidence of a positive impact of health insurance in reducing CHE in the MRH context. It should be noted that this review found very few studies (less than five) that investigated the impact of health insurance on the financial protection of women seeking MRH services in LLMICs. Globally, LMICs bear the highest proportion of OOPE on health. OOPE on health was 43.21% of the total in low-income countries, and 48.17% for lower middle-income countries; meanwhile, the global average is at 18.01% based on the World Bank estimates of 2019 [ 56 ]. Countries that channel larger shares of total health expenditure through prepayment schemes such as health insurance tend to have lower levels of OOPE. As an example, in 2019, the level of OOPE as a proportion of current health expenditure in Indonesia was 34.76%, while in Ghana it was 36.22% which is lower than to the LMIC average. The OOP costs to the patient are found to increase with the increasing level of care. For example in Vietnam, community health facilities had a lower cost for deliveries compared to district and higher-level hospitals [ 57 ]. Health insurance could be key in protecting populations from financial hardship, although, more evidence is necessary to see whether there is substantive impact of health insurance on the financial protection of mothers or women seeking MRH services, especially among the different wealth quintiles, underserved and vulnerable groups of the population.

Inconclusive results on contraception and postnatal care utilisation

The evidence on the impact of health insurance on contraception and postnatal care service utilisation was scarce and inconclusive. Specifically, there was very little evidence on the impact of health insurance on the use of contraception. These findings differ from that of Comfort et al., who found a positive association between health insurance and postnatal care utilisation [ 24 ]. The difference in findings between our study and that of Comfort et al. could potentially be attributed to their inclusion of cross-sectional studies with less rigorous methods.

For contraceptive use, the inconclusive results could be partly explained by the limited insurance coverage for contraceptives in some countries, where the reimbursable contraceptive options are few. Moreover, the reimbursable contraceptive options may not be the most preferred by the society. For example, Ghana has just officially included long-term contraceptive options (such as permanent methods, intrauterine devices (IUDs), implants, and injectables) in the National Health Insurance Scheme benefit package [ 58 ]. On the other hand, cultural, social, and normative practices surrounding postnatal care, as well as the lack of awareness of the clinical postnatal care guidelines may partly explain the inconclusive evidence on the use of postnatal care [ 59 , 60 ]. In addition, despite the importance of postnatal care and contraceptive use in reducing maternal mortality [ 18 ], few studies have evaluated indicators in these areas and the quality of studies examining contraceptive use was moderate to low. The finding regarding the scarcity of evidence on postnatal care in LMICs is not unique to this study, as it has been reported in recent research as well [ 61 ]. Further research is needed to better understand the impact of health insurance on postnatal care and contraceptive utilisation.

Indicators used to measure MRH and the mismatch with international recommendations

Most of the indicators used to measure MRH service utilisation were related to ANC. This may be in part due to the well-established evidence regarding the positive effect of ANC on maternal health related outcomes. Moreover, this aligns with the long standing WHO ANC model (sometimes called basic or focused ANC) introduced in the 1990s, which recommended that a pregnant woman should have at least four ANC visits/contacts during pregnancy [ 62 , 63 ]. However, WHO recently updated their recommendations, increasing the number of ANC visits/contacts to eight [ 64 ]. Unfortunately, our review did not identify any articles that specifically used at least eight visits as an indicator for ANC.

For postnatal care, WHO recommended a minimum of four postnatal care contacts for mothers. These recommended contacts include the first contact within 24 h after delivery, the second contact between 48 and 72 h, the third contact between seven and 14 days, and the fourth contact in the sixth week after delivery [ 65 , 66 ]. However, there was a mismatch between the WHO recommended indicators and the indicators reported in these studies. This indicates that more publicity/sensitization on this important component of the MRH service delivery spectrum is vital. Authors should be encouraged to use recommended indicators to measure the impact of an intervention (health insurance) towards the achievement of global targets and allow for comparison across countries.

Methods used by studies

Propensity score matching was the most popular method used in studies. This conforms to the assertion of Abadie and Cattaneo (2018) that noted an increasing use of matching techniques by researcher partly because of the flexibility of the methods and the failure of ordinary linear regression to estimate conventional treatment effect parameters like ATE and ATET [ 67 ]. In addition, matching makes it possible to estimate treatment effects in the absence of experimental data in evaluation research [ 68 ].Despite the importance of propensity score matching in determining causal inference, it relies on the assumption of conditional independence which may not hold in some instances especially when there are unobservable variables that influence both the treatment and outcome [ 68 ].

Different covariates were used to construct statistical models. Some authors selected covariates based on variable significance level, while others based their selection on the confounding relationship between the exposure and outcome. To have evidence of high certainty, it is necessary to adjust the results based on confounders which can be identified using the directed acyclic graphs [ 67 , 69 ].

Quality of evidence

The quality of the studies included in this review, with regards to the risk of bias, was generally assessed as moderate. It is important to note that increasing the quality of studies in this context can be challenging, as randomised controlled trials are often not feasible or ethically permissible for evaluating policy-related public health interventions, such as health insurance schemes. The absence of randomisation in the allocation of the intervention to participants can introduce various forms of bias, including confounding, which may impact the validity of the study results. Recognizing this, it is essential to thoroughly assess potential drawbacks and biases using appropriate tools [ 30 , 31 ]. The authors tried to overcome this likely consequence of non-randomisation by adjusting for confounders; however, it is difficult to control for all the likely bias. The overall quality of a study can be improved through the randomisation of the intervention (where possible) and the use of causal inference statistical methods that address the potential selection problems that may arise [ 67 , 69 ].

Future research

Although we find that health insurance has a positive impact on the utilisation of ANC; we should be conscious of the intersectionality of evidence. Health insurance interventions may have varying effects across different subgroups within the population. Factors such as age, economic status, and the rural/urban setting can influence how individuals experience and benefit from health insurance coverage [ 47 , 70 ]. A study by Barasa et al. reported that most insurance schemes in sub–Saharan Africa are pro-rich and have minimal benefits for the poor given the low insurance coverage [ 71 ]. The impact of health insurance schemes on utilization and financial protection may vary based on the characteristics/features of the schemes for example organization/design, implementation, enrolment levels, premiums, target population, benefit package [ 21 , 72 ]. If countries are to advance UHC, there is need to understand the intersectionality of the impact, thus conduct more research to investigate the impact of health insurance across geographical domains (rural/urban), across type and level of health providers (private vs public; community-level providers vs secondary- and tertiary-level providers) and vulnerable population subgroups (e.g., people in lower socio-economic quintiles).

Limitations

Our review included studies that were published in English after 2009, which could have led to the omission of studies published in other languages, such as those conducted in French-speaking countries in West Africa or studies before 2010 that may have reported relevant results. We acknowledge that in some contexts, individuals may have private health insurance in addition to the type of health insurance examined in this study, which may have affected the results reported in the included studies. We included studies of various designs, which may have led to variations in the interpretation of results. The use of different covariates in the models employed by the studies could have influenced the magnitude of the reported impact of health insurance.

This study focused on the direction of impact (positive, no change or negative) and significance level of the impact but did not cover the magnitude of the impact. Furthermore, due to the heterogeneity in study design and other characteristics of the included studies, it was not feasible for us to conduct a meta-analysis.

The majority of the included studies used pre-existing datasets to estimate the impact of health insurance. The datasets utilised in this regard were not developed or collected to specifically evaluate health insurance schemes. Such datasets may not be comprehensive in collecting all the relevant data points needed for a robust evaluation of the impact of health insurance.

The quality assessment of the studies was conducted using the ROBINS-I tool – a validated tool recommended by Cochrane for the quality assessment of non-randomised studies [ 20 ]. However the tool does not address problems relating to imprecision of results, where statistical analyses fail to account for clustering or matching of participants [ 31 ]. Such shortfalls may have been overlooked. Therefore, studies that were found to have serious risk of bias were not included in the causal impact analysis, to avoid increasing biases in the summary results.

This review finds evidence supporting the positive impact of health insurance on the utilisation of ANC and delivery care services in low- and lower middle-income settings specially regarding receiving at least four ANC visits, delivery at a health facility and having a delivery assisted by a skilled attendant. Health insurance may contribute to making progress towards UHC, through improving access and utilisation of health services for all. The evidence on financial protection, contraception, and postnatal care is limited and inconclusive. Future evaluations of the impact of health insurance are crucial for countries to identify areas that require improvement, particularly in terms of its impact on vulnerable groups. Further research is needed to assess the impact of health insurance on contraception, postnatal care, and the financial protection of women seeking maternal and reproductive health services. Such work would contribute to a deeper understanding of the potential benefits and limitations of health insurance in these critical areas.

Availability of data and materials

The extracted data analysed during the current study is available from corresponding author on reasonable request.

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Acknowledgements

Open access funding provided by Lund University. This study was funded by the Swedish Research Council.

The funder of the study had no role in study design, data collection, data analysis, data interpretation, or writing of the report.

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Conceptualisation: – JS, BE, FM, JK. Developing and carrying out search strategy: – JK, PBT. Screening of articles: – SPK, JK, PBT. Data extraction, and quality assessment: – JK, PBT. Validation: – JK, PBT, JS. Data curation and analysis: – JK, PBT, AHK. Funding acquisition: – JS, BE, FM. Methodology: – JK, PBT, AHK. Project administration: – JK. Supervision: – JS, BE, FM. writing – original draft: – JK. writing review & editing: – JK, PBT, AHK, FM, BE, JS.

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Kazibwe, J., Tran, P.B., Kaiser, A.H. et al. The impact of health insurance on maternal and reproductive health service utilization and financial protection in low- and lower middle-income countries: a systematic review of the evidence. BMC Health Serv Res 24 , 432 (2024). https://doi.org/10.1186/s12913-024-10815-5

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DOI : https://doi.org/10.1186/s12913-024-10815-5

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A robust synthesis route of confined carbyne

• Research Article
• Published: 11 April 2024

Cite this article

• Yanghao Feng 1   na1 ,
• Wendi Zhang 2   na1 ,
• Kunpeng Tang 1 ,
• Yingzhi Chen 1 ,
• Jiou Zhang 1 ,
• Kecheng Cao 2 ,
• Weili Cui 1 &
• Lei Shi 1  

The unique mechanical, optical, and electrical properties of carbyne, a one-dimensional allotrope of carbon, make it a highly promising material for various applications. It has been demonstrated that carbon nanotubes (CNTs) can serve as an ideal host for the formation of confined carbyne (CC), with the yield being influenced by the quality of the carbon nanotubes for confinement and the carbon source for carbyne growth. In this study, a robust synthesis route of CC within CNTs is proposed. C 70 was utilized as a precursor to provide an additional carbon source, based on its ability to supply more carbon atoms than C 60 at the same filling ratio. Multi-step transformation processes, including defect creation, were designed to enhance the yield of CC. As a result, the yield of CC was significantly increased for the C 70 encapsulated single-walled CNTs by more than an order of magnitude than the empty counterparts, which also surpasses that of the double-walled CNTs, making it the most effective route for synthesizing CC. These findings highlight the importance of the additional carbon source and the optimal pathway for CC formation, offering valuable insights for the application of materials with high yield.

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Acknowledgements

This work was supported by the Guangzhou Basic and Applied Basic Research Foundation (No. 202201011790), the National Natural Science Foundation of China (No. 51902353), the Shanghai Rising-Star Program (No. 21QA1406300), the Fundamental Research Funds for the Central Universities, Sun Yatsen University (No. 22lgqb03), the Characteristic Innovation Project of Guangdong Provincial Department of Education (No. 2022KTSCX001), the State Key Laboratory of Optoelectronic Materials and Technologies (No. OEMT-2022-ZRC-01), and the Open Project of Guangdong Province Key Lab of Display Material and Technology (No. 2020B1212060030).

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Yanghao Feng and Wendi Zhang contributed equally to this work .

Authors and Affiliations

State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, Guangdong Basic Research Center of Excellence for Functional Molecular Engineering, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China

Yanghao Feng, Kunpeng Tang, Yingzhi Chen, Jiou Zhang, Weili Cui & Lei Shi

School of Physical Science and Technology and Shanghai Key Laboratory of High-resolution Electron Microscopy, Shanghai Tech University, Shanghai, 201210, China

Wendi Zhang & Kecheng Cao

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Correspondence to Kecheng Cao , Weili Cui or Lei Shi .

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Feng, Y., Zhang, W., Tang, K. et al. A robust synthesis route of confined carbyne. Nano Res. (2024). https://doi.org/10.1007/s12274-024-6571-z

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Received : 12 December 2023

Revised : 02 February 2024

Accepted : 13 February 2024

Published : 11 April 2024

DOI : https://doi.org/10.1007/s12274-024-6571-z

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Feature Article: S&T Helps the NFL Play Defense Around the Big Game

It is an unfortunate, but all too real, aspect of our daily lives that security has to be top of mind when staging a big event, and there is no event bigger than the Super Bowl. The planning and organization that goes into making something like the Super Bowl happen seamlessly and securely, and come off without a hitch, begins almost as soon as the previous one ends.

At this year’s game, which took place in February at Allegiant Stadium in Las Vegas, the Science and Technology Directorate (S&T) helped to deploy a new and innovative technology solution to assist the Department of Homeland Security, federal, state, and local law enforcement, and event security teams with keeping everyone safe.

In the week leading up to the game, S&T’s Physical Security Program worked with partners at the U.S. Army Engineer Research and Development Center (ERDC) and Cybersecurity and Infrastructure Security Agency (CISA) to deploy the Ready Armor Protection for Instant Deployment (RAPID) system in support of the National Football League (NFL).

RAPID is a quickly deployable barrier for critical asset protection and urban operations, that uses a hydraulic system and wheels to allow for it to be set up with just a few people. Each RAPID barrier is integrated into a container for storage and transport.

Once on site, each section can be expanded to 35 feet during use, and when fully expanded, RAPID provides ballistic/fragmentation protection, intrusion protection, and line-of-sight denial. RAPID is scalable, meaning each barrier section can connect to as many additional sections as required.

RAPID does not depend on heavy equipment, special tools, or an electrical power source to be deployed or recovered. RAPID provides protection at least seven times faster than the most comparable system (a similar modular protective system) and is 70 times faster than building a sandbag wall of similar size.

Once in place during this year’s Super Bowl Weekend, RAPID was evaluated by multiple DHS agencies, Las Vegas law enforcement, and Live Nation, an American multinational entertainment company. One of the deployments was at the NFL Honors event at Resorts World, where two RAPID barrier sections, comprising 70 total feet of protection, shielded critical parts of the venue from potential vehicle ramming and improvised explosive device detonations.

“The location for this deployment was next to an important traffic artery that could not be shut down and had vulnerable high-capacity entry and exit points, which presented an ideal opportunity to showcase RAPID’s capabilities,” said Physical Security Program Manager Ali Fadel. “RAPID was able to fill gaps in the venue’s security posture, while proving to be the most mobile and effective solution.”

S&T escorted NFL senior personnel to view the RAPID barrier who were impressed with its capabilities. Once in place, the RAPID barrier was wrapped with a decorative cover—an important aspect of the system because it allows the barrier to blend in, concealing its actual dimensions and function from anyone who might seek to break through to the protected area behind.

Following the event, a final report prepared by ERDC concluded that all who participated in the deployment liked how portable the system was. Specifically, one participant was interested in taking advantage of the mobility of the system with a modified version that was shorter for use primarily as a hostile vehicle barrier.

Participants are compiling a list of requirements to submit to ERDC for further RAPID development; for instance, some of the DHS stakeholders thought a customized version of RAPID could be designed with a shallower footprint and a hinged panel, allowing the height of the barrier to be increased quickly without escalating a potential crowd control situation. This kind of deployment, and the resulting feedback and ongoing refinement, is an excellent example of the kind of valuable test and evaluation work that is undertaken by S&T and illustrates the complex and vital role S&T plays as the research and development home of DHS.

Ali Fadel summed up the weekend for RAPID, “We are learning more about the versatility of the units with each deployment.  As we converse with the law enforcement community, venue owners, first responders, and other R&D personnel, we learn about the possible deployments, enhancements, and uses for this versatile barrier.” 

RAPID was also deployed at the 2023 NFL Draft in Kansas City. Learn more about that in S&T’s Technologically Speaking podcast episode with Ali Fadel, Any Place Where People Congregate . For related media inquiries, contact [email protected] .

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First report of a prolonged bite by a Western Whip Snake, Hierophis viridiflavus carbonarius (Bonaparte 1833) (Serpentes, Colubridae), resulting in pronounced local oedema

• Fabio Savini Via Sant’Agà, 47521 Cesena, Italy

Although extensive research has been conducted on snake venoms, the effects of bites inflicted by non-front-fanged colubroid snakes remain incompletely understood, particularly for species of uncertain medical relevance. The Western Whip Snake ( Hierophis viridiflavus ) is a colubrid snake typically classified as non-venomous and harmless to humans. Nevertheless, old works reporting the presence of Duvernoy's glands in this species raise questions regarding its presumed lack of venom. This report presents the first case of a prolonged bite from a wild Western Whip Snake ( Hierophis viridiflavus carbonarius ) that occurred in Italy, and provides a detailed account of the resulting effects. The primary symptom experienced by the bitten subject was painless, marked local oedema, which subsided within 24h after the bite. The clinical manifestations observed in the current study suggest that Hierophis viridiflavus could have the potential to inflict bites that lead to mild local effects consistent with envenoming.

Copyright (c) 2024 Ignazio Avella, Fabio Savini, Matteo Di Nicola

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