sample literature review in computer science

Computer Science

• Key resources
• Databases and journal articles
• Standards and patents

What is a literature review?

Finding the gaps and advances in your area, literature review resources, annotated bibliography.

A literature review is a survey and critical analysis of what has been written on a particular topic, theory, question or method.

What is its purpose?

• justify your research
• provide context for your research
• ensure that the research has not been done before
• highlight flaws in previous research
• identify new ways, to interpret and highlight gaps in previous research
• signpost a way forward for further research
• show where your research fits into the existing literature
• Literature reviews guide The Literature reviews guide contains detailed information on the process of searching for and producing literature reviews.
• Scopus A multidisciplinary abstract and citation database of peer reviewed literature, book reviews and conference proceedings.
• Web of Science A collection of citation databases and citation analysis tools covering the sciences, social sciences, arts and humanities.
• IEEE Xplore digital library Provides full-text access to IEEE and IEE transactions, journals, magazines and conference proceedings published since 1988 and current IEEE Standards.
• ACM digital library publications Full text of every article published by the Association for Computing Machinery (ACM) and bibliographic citations from major publishers in computing
• Annual reviews online This database provides review journals from across the sciences, with articles that review significant primary research literature.
• Cited reference searching

Books and other resources for approaches and methods on doing a literature review. See the Literature reviews guide .

An annotated bibliography provides:

• a list of references presenting a brief summary of the main arguments or ideas of each resource.
• a critique or evaluation of the resource's usefulness, reliability, objectivity or bias
• a reflection on how the resource fits into your research.
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Computer Science and Engineering

• Getting Started
• Keeping Current

Introduction

Gather Your Tools

Determine the Project's Scope

Create the Search Strategy

Determine What Resources to Use

Search, read, refine, repeat.

Saved Searches, Alerts and Feeds

• STEM Biographies & Info
• Writing & Citing

This page focuses on how to do an in-depth literature review for a dissertation, thesis, grant application or lengthy term paper in electrical engineering.  

• For a more general description of what an in-depth literature review is and how it looks, see our guide on " Literature Reviews and Annotated Bibliographies " created by Ed Oetting, history and political science librarian.
• For lower-level engineering undergraduate students who are doing a short term paper, the " How to Research a Topic " page on the " Engineerng Basics" guide may be more applicable.

Library Account Is your library account clear of fines?   If not, you may not be allowed to check out more books nor renew books you already have.  All library notices are sent via email to your "asu.edu" address; if you prefer to receive email at a different address make sure you have forwarded your asu.edu correctly.  Also, make sure that your spam filter allows the library email to come through. 

Illiad (Interlibrary Loan) Account   If you don't already have an ILLiad account, please register for one.  Interlibrary loan services will get you material not available at the ASU Library and also scan or deliver materials from the libraries on the other ASU campuses.

Determine the Project's Scope.

Do you know what you are looking for?  Can you describe your project using one simple sentence or can you phrase the project as a question?  Without a clear idea of the project, you may not be able to determine which are the best resources to search, what terminology should be used in those resources, and if the results are appropriate and sufficient.    

If you're having difficulty getting your project described succinctly, try using a PICO chart to identify the concepts involved:

• P is the popluation, problem, predicament or process
• I is the intervention or improvement
• C is what you'll compare your intervention/improvment to, and
• O is the outcome (or results of the comparison of I and C ) 

For example: 

Your client, the owner of a nuclear power generating facility, has had several less than optimal safety inspections recently.  The inspectors have singled out operator error as a major concern and have required changes in employee training.  But is more training the solution?  The employees complain that the plant's poorly designed control room hampers their ability to respond to non-standard situations.  Could a redesign improve performance and decrease the occurance of unsafe events?   Your client wants more than just your opinion, he wants to see the data to back it up.   So, what can you find in the literature?

Here's one way that the PICO chart could be filled out:     

• P =   nuclear power safety  
• I  = human factors engineering
• C  =  additional training; little or no human factors engineering used  
• O = accident rate or safety inspection comparison

And here are examples of possible search statements:  

• I am looking for ways that human factors engineering can improve safety in the nuclear power industry.
• Is additional training or employing human factors engineering the better method for reducing safety violations in a nuclear power plant? 

Your research will always start with a " P AND I " search; those are the most important pieces of the puzzle.  However, once you have the results from that search, you'll need to know where you want to go with those results; that's when the C and O concepts need to be considered.  

 Also, don't forget --- determine if your project has limits.  For example:

• Are you reviewing the literature only within a specific time frame?
• Are you looking at English-language material only?
• Are you considering research from just the United States or worldwide?
• Are there types of material you won't be covering (trade magazines, patents, technical reports, etc.)?  

Take the simple sentence or question that describes what you are looking for.  What are the concepts in the sentence? Are there synonyms that describe the same concept?   If you filled out a PICO chart, concentrate on the  P (problem) and the  I (intervention) for the concept chart.  

Concept Chart:

Concept 1:   _______  OR _______  OR _______  AND Concept 2:   _______   OR   _______  OR   _______  AND Concept 3:  _______  OR  _______  OR   _______ 

  Example:  

I am looking for ways that human factors engineering can improve safety in the nuclear power industry. 

Concept 1:   nuclear power    OR _ nuclear industry _____   AND Concept 2:   _safety___  OR   _accident prevention____   AND Concept 3: _ human factors engineering ___   

What resources you'll use for your literature review depends on what types of materials you want to find.  

• Background Information The more you know about a topic, the better you'll be able to research it.  You'll be familiar with the terminology, understand the underlining science/technology and be aware of the issues in the field. Most importantly, you'll be able to understand what you've retrieved from your search.  But no matter how much you know before hand you'll likely run across terms and concepts with which you're unfamiliar.    Materials such as encyclopedias, dictionaries and handbooks will not only help you learn about the basics of your topic before you begin your search but they'll also help you understand the terminology used in the documents you found from your literature review.    You'll find these types of resources listed on the Dictionaries and Handbooks pages on this guide.
• Books The large size of books (usually 100-500 pages) allows a topic to be studied braodly, covering many different issues.  Conversely, the large size also allows for a specific aspect of the topic to be covered in great detail.  Because of the time it takes to publish, sci-tech books generally do not contain the most current information. To find print and online books from both the ASU Library as well as in other libraries, see the Books page on this guide.
• Conference Papers Scientists and engineers frequently present new findings at conferences before these findings are written up in journal articles or books.  Not every conference, however, publishes it proceedings.  In some cases, conferences publish only a few of the papers presented but not all.   Many resources that help you find journal articles, may also be used to find conference papers, see the Articles page on this guide.
• Journal and Trade Magazine Articles Articles in journals (also called magazines) are short, usually 5-20 pages in length and cover a specific finding, experiment or project.  Articles in scholary journals are usually written by academics or professional scientists/engineers and are aimed at others at the same level.   Articles in trade journals/magazines are written by the journal staff and report on industry news suchs as sales, mergers, prices, etc.   To find journal and trade magazine articles, use the resources listed on the Articles page on this guide. 
• Patents Patents are grants from governments that gives the inventor certain rights of manufacture.  Patents provide a wealth of information for how a technology is being advanced and by which companies.  It is frequently stated that 80% of the information in patents never appears elsewhere in the literature. 
• To identify patents granted in the U.S. and internationally see the " Searching for Patents " guide.
• To see statistical information for U.S. patents by technology class see the US Patent and Trademark's website.
• Technical Reports Technical reports are part of the "gray literature";  gray literature refers to documents that are not published commercially, hence they are difficult to both identify and find.  Technical reports focus on a specific experiment or research project and are meant to convey the results of the experiment or project back to the funding organization.  In the United States, common sources of technical reports are the government agencies that sponsor research projects.  Reports generated within a private corporation and funded soley by that corporation are seldom ever available to anyone outside of the company.      To find technical reports, use the resources listed on the Technical Reports page on this guide.     

Search, Read, Refine and Repeat

Now it's time to apply your search strategy in the resources you've decided to use.

• Use the Advanced Search feature (or whatever search is set up with the 3 lines of boxes) and enter your search strategy just as you recorded in your search strategy chart.  Don't forget to set your limits.   If the resource only provides a single search box, rearrange your chart from vertical into horizontal so that the search statement looks like this:   (Concept#1 OR synonym) AND (Concept#2 OR synonym) AND (Concept#3 OR synonym) Example: (nuclear power OR nuclear industry) AND (safety OR accident prevention) AND (human factors engineering)
• Examine the results to find the most appropriate items.  Keep your one-sentence project description (and/or your PICO chart) in mind to help you stay on track.
• Export the records/citations you want to keep into a citation manager.
• If there are subjects (may also be called subject headings, index terms, descriptors or controlled vocabulary) assigned to each item, make sure that those also transferred into a citation manager.  If not, add them manually.
• Get the full text of the items 
• Read the full text of the items and look at the subjects assigned to the item and consider:
• Do I have to change (narrow) my topic to something more specific because I'm finding way too much? 
• Do I have to change (broaden) my topic because I can't find enough about it? 
• Is there additional terminology for my topic/concepts that I hadn't included in my original search?
• Redo your search strategy according to what you found in step #6 and rerun the search in the resources again.
• You may need to repeat this cycle several times before you are able to identify the best terminology to use in each resource. 

If there will be several months in between when you search the literature and when you turn in the paper, consider setting up alerts and feeds so that you are notified should new items about your topic appear.   How you set up an alert or feed will vary.  In most cases you'll be required to set up a personal account or profile with the journal or database --- there is no charge for this but you will have to identify yourself and provide an email address.  

For instructions on setting up alerts and feeds, see the " Keep Current " page.

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Computer Science (UNH Durham): Literature Reviews

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Technical Reports

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Bibliographic Management Software

Zotero is a free, open source bibliographic management tool that operates as an extension of the Firefox browser.   Zotero allows the collection of citations to any kind of material and automatically formats bibliographies in almost any style.  Zotero also has many search, tagging, and note taking features.  Visit the Zotero quick start guide to learn more. 

EndNote is offered through the Web of Science database.  It enables users to collect, organize, and format citations the Web of Science database and other ISI products and to input citations to any other outside matrials.  To register, go into the Web of Science database and click on "My EndNote Web" at the top of the screen.  Endnote accounts can be accessed from any computer at the institution or off-campus through Blackboard or VPN. 

• Electronic Colloquium on Computational Complexity Full text collection of reports, papers, and notes searchable by keyword or author. Includes a browsable keyword list.
• National Technical Information Service (NTIS) Collection of citations to reports on government funded research. If you need materials cited on the NTIS site please check WorldCat or talk to your librarian.
• Science.gov Allows searches across many government databases and websites. Content is not limited to technical reports. Often full text of reports is available.
• Virtual Technical Reports Center Links to hundreds of university, government, and project websites containing technical reports and other resources. more... less... Maintained by the University of Maryland Libraries.

Getting Started

The goal of a literature review is to find all the relevant publications on a topic and to then summarize and synthesize that information. A literature review can help you find areas where further research is needed, narrow a research topic, or determine if a thesis question is unique. Talk to your advisor for help defining your research question. For help with library resources, talk to your librarian; they can help you find a combination of resources that will result in a comprehensive search.

Indexes and Databases

• ACM Digital Library This link opens in a new window Provides access to ACM journals, newsletters, and conference proceedings. Includes bibliographic information, abstracts, reviews, and the full text for articles along with selected works published by affiliated organizations. Dates of coverage: 1947-current
• CiteSeerX Indexes computer and information science literature and includes full text of articles and citation statistics. Allows the full text of articles to be searched.
• IEEE Xplore This link opens in a new window A digital library providing full text access to the world's highest quality technical literature in electrical engineering, computer science, and electronics. It contains full text documents from IEEE journals, transactions, magazines, letters, conference proceedings, standards, and IET (Institution of Engineering and Technology) Conferences. UNH no longer has access to IET Journals.
• Web of Science This link opens in a new window Facilitates research-level interdisciplinary search. Use the Basic Search to locate articles in high-impact scholarly journals in science, social science, arts, and humanities. Use the unique Cited Reference search for articles that cite an article you already know of, so you can track citations forward in time.
• INSPEC This link opens in a new window The world's leading resource for coverage of research literature in physics, including astronomy and astrophysics. Its other subject strengths are electrical engineering; control, and computing, including information technology. International journals and conference proceedings are covered, with selected indexing of books and reports. This resource allows searching by specialized fields. Dates of coverage: 1896-current
• Computing Research Repository (CoRR) Archives computer science papers with some coverage back to 1993. Includes full text of all papers. Frequently updated. more... less... Sponsored by ACM, the arXiv.org e-Print archive, NCSTRL (Networked Computer Science Technical Reference Library), and AAAI.
• DBLP Computer Science Bibliography Provides citations to articles in major computer science journals and conference proceedings and in some cases links to full-text versions of articles (look for the words "Electronic Editions.") Search by author or keyword, or browse by journal, conference proceeding, or broad subject area.

Finding Dissertations and Theses

• Dissertations & Theses Global This link opens in a new window Comprehensive collection of full-text dissertations and theses. Official digital dissertations archive for the Library of Congress and considered the database of record for graduate research. Note: Full text for certain publications is subject to market availability. Dates of coverage: 1861-current
• Networked Digital Library of Theses and Dissertations Searches almost 4 million dissertations and theses from around the world. To focus your search, try the "advanced search tips" and use the facets on the left when viewing your search results.
• OpenDOAR Allows searches of the contents of institutional repositories which may contain dissertations that are not available through the Digital Dissertations database. Repositories contents are not limited to dissertations; to limit your search add "dissertation" or "thesis" to your keywords in the search box.
• TEL (thèses-EN-ligne) Part of HAL , this database is a multidisciplinary collection of self-submitted theses and dissertations.

Engineering & Physical Sciences Librarian

Print Indexes

• ACM Guide to Computing Literature by Association for Computing Machinery Call Number: Eng/Math/CS Library QA76 .A8 Index to books, papers, reports, articles in major journals of computing and related fields, conferences and symposia. Available online from 1985 to present at the ACM website. Available only in print from 1977 to 1984.
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HELP MAUI • JOB OPENINGS

Information and Computer Sciences

University of Hawai‘i at Mānoa

Literature Review Guidelines

The Portfolio part of the Ph.D. degree requires that each student write a literature review (as described here. This document provides broad guidelines for writing the literature review.

A literature review is a self-contained document that is focused on a particular area of Computer Science research, and that is targeted to Computer Science researchers that are not expert in the particular area of focus. After reading the literature review, the audience should feel like they can engage in an informed and intelligent conversation about the focus area.

The literature review should address the following points:

• Why is the focus area interesting?
• What are the challenges and the key research questions?
• What are the known approaches results, their strengths and their weaknesses?
• What are important open research questions?

IMPORTANT #1: A key aspect of the literature review is that it should not be merely an enumeration of previous work. It should have, either interspersed throughout or as a last section, a discussion with your own thoughts. Such thoughts could be your own evaluation of the merits/drawbacks of proposed approach beyond those already identified in the literature. Also, a good literature review almost always includes a well-argued discussion of promising research directions for future work in the area. IMPORTANT #2: The literature review is not a Ph.D. dissertation proposal. The literature review should be written objectively, unbiased by your own work in the area, if any. You do not have to justify the relevance of your own work and its promises in this document. However, this type of justification is mandatory in the Ph.D. proposal document and defense.

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Methodology

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

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

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

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

There are five key steps to writing a literature review:

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

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

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Table of contents

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

• Quick Run-through
• Step 1 & 2

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

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

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

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See an example

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

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

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

Download Word doc Download Google doc

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

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

Make a list of keywords

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

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

Search for relevant sources

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

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

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

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

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

For each publication, ask yourself:

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

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

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

Take notes and cite your sources

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

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

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

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

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

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

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

Chronological

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

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

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

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

Methodological

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

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

Theoretical

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

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

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

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

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

As you write, you can follow these tips:

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

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

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

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

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

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

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

 Statistics

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

Research bias

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

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

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

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

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

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

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

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

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

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Computer Science: Systematic Reviews

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What Is a Systematic Review?

Regular literature reviews are simply summaries of the literature on a particular topic. A systematic review, however, is a comprehensive literature review conducted to answer a specific research question. Authors of a systematic review aim to find, code, appraise, and synthesize all of the previous research on their question in an unbiased and well-documented manner. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) outline the minimum amount of information that needs to be reported at the conclusion of a systematic review project. 

Other types of what are known as "evidence syntheses," such as scoping, rapid, and integrative reviews, have varying methodologies. While systematic reviews originated with and continue to be a popular publication type in medicine and other health sciences fields, more and more researchers in other disciplines are choosing to conduct evidence syntheses. 

This guide will walk you through the major steps of a systematic review and point you to key resources including Covidence, a systematic review project management tool. For help with systematic reviews and other major literature review projects, please send us an email at  [email protected] .

Getting Help with Reviews

Organization such as the Institute of Medicine recommend that you consult a librarian when conducting a systematic review. Librarians at the University of Nevada, Reno can help you:

• Understand best practices for conducting systematic reviews and other evidence syntheses in your discipline
• Choose and formulate a research question
• Decide which review type (e.g., systematic, scoping, rapid, etc.) is the best fit for your project
• Determine what to include and where to register a systematic review protocol
• Select search terms and develop a search strategy
• Identify databases and platforms to search
• Find the full text of articles and other sources
• Become familiar with free citation management (e.g., EndNote, Zotero)
• Get access to you and help using Covidence, a systematic review project management tool

Doing a Systematic Review

• Plan - This is the project planning stage. You and your team will need to develop a good research question, determine the type of review you will conduct (systematic, scoping, rapid, etc.), and establish the inclusion and exclusion criteria (e.g., you're only going to look at studies that use a certain methodology). All of this information needs to be included in your protocol. You'll also need to ensure that the project is viable - has someone already done a systematic review on this topic? Do some searches and check the various protocol registries to find out. 
• Identify - Next, a comprehensive search of the literature is undertaken to ensure all studies that meet the predetermined criteria are identified. Each research question is different, so the number and types of databases you'll search - as well as other online publication venues - will vary. Some standards and guidelines specify that certain databases (e.g., MEDLINE, EMBASE) should be searched regardless. Your subject librarian can help you select appropriate databases to search and develop search strings for each of those databases.  
• Evaluate - In this step, retrieved articles are screened and sorted using the predetermined inclusion and exclusion criteria. The risk of bias for each included study is also assessed around this time. It's best if you import search results into a citation management tool (see below) to clean up the citations and remove any duplicates. You can then use a tool like Rayyan (see below) to screen the results. You should begin by screening titles and abstracts only, and then you'll examine the full text of any remaining articles. Each study should be reviewed by a minimum of two people on the project team. 
• Collect - Each included study is coded and the quantitative or qualitative data contained in these studies is then synthesized. You'll have to either find or develop a coding strategy or form that meets your needs. 
• Explain - The synthesized results are articulated and contextualized. What do the results mean? How have they answered your research question?
• Summarize - The final report provides a complete description of the methods and results in a clear, transparent fashion. 

Adapted from

Types of reviews, systematic review.

These types of studies employ a systematic method to analyze and synthesize the results of numerous studies. "Systematic" in this case means following a strict set of steps - as outlined by entities like PRISMA and the Institute of Medicine - so as to make the review more reproducible and less biased. Consistent, thorough documentation is also key. Reviews of this type are not meant to be conducted by an individual but rather a (small) team of researchers. Systematic reviews are widely used in the health sciences, often to find a generalized conclusion from multiple evidence-based studies. 

Meta-Analysis

A systematic method that uses statistics to analyze the data from numerous studies. The researchers combine the data from studies with similar data types and analyze them as a single, expanded dataset. Meta-analyses are a type of systematic review.

Scoping Review

A scoping review employs the systematic review methodology to explore a broader topic or question rather than a specific and answerable one, as is generally the case with a systematic review. Authors of these types of reviews seek to collect and categorize the existing literature so as to identify any gaps.

Rapid Review

Rapid reviews are systematic reviews conducted under a time constraint. Researchers make use of workarounds to complete the review quickly (e.g., only looking at English-language publications), which can lead to a less thorough and more biased review. 

Narrative Review

A traditional literature review that summarizes and synthesizes the findings of numerous original research articles. The purpose and scope of narrative literature reviews vary widely and do not follow a set protocol. Most literature reviews are narrative reviews. 

Umbrella Review

Umbrella reviews are, essentially, systematic reviews of systematic reviews. These compile evidence from multiple review studies into one usable document. 

Grant, Maria J., and Andrew Booth. “A Typology of Reviews: An Analysis of 14 Review Types and Associated Methodologies.” Health Information & Libraries Journal , vol. 26, no. 2, 2009, pp. 91-108. doi: 10.1111/j.1471-1842.2009.00848.x .

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A literature review is a scholarly paper, which includes the current knowledge including substantive findings, as well as theoretical and methodological contributions to a particular topic. Find links to some literature review tutorials:

• What is a literature review
• Literature Review
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Plagiarism is  the practice of taking someone else's work or ideas and passing them off as one's own. Find below links to  UG's plagiarism policy and guidelines for using Turnitin Software.

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​Other relevant documents:

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A review article is an article that summarizes the current state of understanding on a topic. A review article surveys and summarizes previously published studies, rather than reporting new facts or analysis.

• Annual Review of Computer Science
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Research Methods Databases and Articles

Research methods databases/articles help you to find examples of different research methods to facilitate the design of your own research.

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• Using Ontology Engineering Methods to Improve Computer Science and Data Science Skills more... less... We discuss some methodological aspects of ontology design process and enriching of existing free accessible ontologies and show how suggested methods and software tools help IT-specialists including master students to implement their research work and participate in real world projects. The role of visual data exploration tools for certain issues under discussion and some use cases are discussed.

List of Masters theses, presented to the Computer Science Department, which can be accessed, full-text, from the UG Institutional Repository

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Faculty Research papers available in the UG Institutional Repository, either in full text or abstract only.

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"Literature review," "systematic literature review," "integrative literature review" -- these are terms used in different disciplines for basically the same thing -- a rigorous examination of the scholarly literature about a topic (at different levels of rigor, and with some different emphases).  

1. Our library's guide to Writing a Literature Review

2. Other helpful sites

• Writing Center at UNC (Chapel Hill) -- A very good guide about lit reviews and how to write them
• Literature Review: Synthesizing Multiple Sources (LSU, June 2011 but good; PDF) -- Planning, writing, and tips for revising your paper

3. Welch Library's list of the types of expert reviews

Doing a good job of organizing your information makes writing about it a lot easier.

You can organize your sources using a citation manager, such as refworks , or use a matrix (if you only have a few references):.

• Use Google Sheets, Word, Excel, or whatever you prefer to create a table
• The column headings should include the citation information, and the main points that you want to track, as shown

Synthesizing your information is not just summarizing it. Here are processes and examples about how to combine your sources into a good piece of writing:

• Purdue OWL's Synthesizing Sources
• Synthesizing Sources (California State University, Northridge)

Annotated Bibliography  

An "annotation" is a note or comment. An "annotated bibliography" is a "list of citations to books, articles, and [other items]. Each citation is followed by a brief...descriptive and evaluative paragraph, [whose purpose is] to inform the reader of the relevance, accuracy, and quality of the sources cited."*

• Sage Research Methods (database) --> Empirical Research and Writing (ebook) -- Chapter 3: Doing Pre-research  
• Purdue's OWL (Online Writing Lab) includes definitions and samples of annotations  
• Cornell's guide * to writing annotated bibliographies  

* Thank you to Olin Library Reference, Research & Learning Services, Cornell University Library, Ithaca, NY, USA https://guides.library.cornell.edu/annotatedbibliography

What does "peer-reviewed" mean?

• If an article has been peer-reviewed before being published, it means that the article has been read by other people in the same field of study ("peers").
• The author's reviewers have commented on the article, not only noting typos and possible errors, but also giving a judgment about whether or not the article should be published by the journal to which it was submitted.

How do I find "peer-reviewed" materials?

• Most of the the research articles in scholarly journals are peer-reviewed.
• Many databases allow you to check a box that says "peer-reviewed," or to see which results in your list of results are from peer-reviewed sources. Some of the databases that provide this are Academic Search Ultimate, CINAHL, PsycINFO, and Sociological Abstracts.

What kinds of materials are *not* peer-reviewed?

• open web pages
• most newspapers, newsletters, and news items in journals
• letters to the editor
• press releases
• columns and blogs
• book reviews
• anything in a popular magazine (e.g., Time, Newsweek, Glamour, Men's Health)

If a piece of information wasn't peer-reviewed, does that mean that I can't trust it at all?

No; sometimes you can. For example, the preprints submitted to well-known sites such as  arXiv  (mainly covering physics) and  CiteSeerX (mainly covering computer science) are probably trustworthy, as are the databases and web pages produced by entities such as the National Library of Medicine, the Smithsonian Institution, and the American Cancer Society.

Is this paper peer-reviewed? Ulrichsweb will tell you.

1) On the library home page , choose "Articles and Databases" --> "Databases" --> Ulrichsweb

2) Put in the title of the JOURNAL (not the article), in quotation marks so all the words are next to each other

3) Mouse over the black icon, and you'll see that it means "refereed" (which means peer-reviewed, because it's been looked at by referees or reviewers). This journal is not peer-reviewed, because none of the formats have a black icon next to it:

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Title: related work and citation text generation: a survey.

Abstract: To convince readers of the novelty of their research paper, authors must perform a literature review and compose a coherent story that connects and relates prior works to the current work. This challenging nature of literature review writing makes automatic related work generation (RWG) academically and computationally interesting, and also makes it an excellent test bed for examining the capability of SOTA natural language processing (NLP) models. Since the initial proposal of the RWG task, its popularity has waxed and waned, following the capabilities of mainstream NLP approaches. In this work, we survey the zoo of RWG historical works, summarizing the key approaches and task definitions and discussing the ongoing challenges of RWG.

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• Published: 18 April 2024

Effects of human milk odor stimulation on feeding in premature infants: a systematic review and meta-analysis

• Yangyang Qin 1 ,
• Shu Liu 1 ,
• Yanming Yang 1 ,
• Yuan Zhong 1 ,
• Danshi Hao 2 &
• Han Han 3  

Scientific Reports volume  14 , Article number:  8964 ( 2024 ) Cite this article

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Previous studies suggested odor stimulation may influence feeding of premature neonates. Therefore, this systematic review and meta-analysis of randomized controlled trials was conducted to assess the effect of human milk odor stimulation on feeding of premature infants. All randomized controlled trials related to human milk odor stimulation on feeding in premature infants published in PubMed, Cochrane, Library, Medline, Embase, Web of science databases and Chinese biomedical literature databases, China National Knowledge Infrastructure, China Science and Technology Journal Database (VIP) and Wanfang Chinese databases were searched, and The Cochrane Handbook 5.1.0 was used to evaluate the quality and authenticity of the literature. Relevant information of the included studies was extracted and summarized, and the evaluation indexes were analyzed using ReviewManager5.3. The retrieval time was from the establishment of the database to July 28, 2022.12 articles were assessed for eligibility, and six randomized controlled studies were eventually included in the meta-analysis (PRISMA). A total of 6 randomized controlled studies with 763 patients were finally included in the study, and the quality evaluation of literatures were all grade B. Human milk odor stimulation reduced the transition time to oral feeding in premature infants [SMD = − 0.48, 95% CI (− 0.69, − 0.27), Z = 4.54, P  < 0.00001] and shortened the duration of parenteral nutrition [MD = − 1.01, 95% CI (− 1.70, − 0.32), Z = 2.88, P  = 0.004]. However, it did not change the length of hospitalization for premature infants [MD = − 0.03, 95% CI (− 0.41, 0.35), Z = 0.17, P  = 0.86]. The implementation of human milk odor stimulation can reduce the transition time to oral feeding and the duration of parenteral nutrition in premature infants, but further studies are needed to determine whether it can reduce the length of hospital stay in premature infants. More high-quality, large-sample studies are needed to investigate the effect of human milk odor stimulation on the feeding process and other outcomes in premature infants.

Introduction

Premature infants are babies born alive before 37 weeks of pregnancy are completed. According to the relevant World Health Organization (WHO) report, 15 million premature infants are born every year in the world 1 . Preterm birth is an important public health issue, as it is associated to a high burden of mortality and morbidities 2 . Premature infants are at high risk for aspiration due to poor coordination of sucking and swallowing 3 . Thus, they usually need tube feeding for nutritional needs with a gradual transition to oral feeding. Premature infants need to start oral feeding at the youngest possible age to improve survival and recovery 4 .

It has been shown 5 , 6 , 7 that fetal olfactory receptors begin to appear in the 8th week of pregnancy, ciliated olfactory receptors mature in the 24th week, and the nasopharyngeal epithelium can express olfactory marker proteins in the 28th week. Premature infants, just like full-term infants, possess a more advanced olfactory system at birth, enabling them to detect, selectively process, retain, and recall odor information. They are able to distinguish between different odors, including those of human milk, even without history of postpartum exposure to such odors 8 , 9 . Olfactory stimulus refers to an environmental stimulus that uses a familiar odor or aromatic odor and is transmitted to the cerebral cortex through olfactory receptors and olfactory nerves to produce an olfactory response. In recent years, an increasing number of studies have used olfactory stimulation as a non-drug intervention to improve the effects of feeding. For example, human milk odor stimulation has a sedative effect on neonates 10 , 11 and relieve the pain 12 caused by venipuncture. The milk odor can also prevent apnea 13 and improve oxygen saturation 14 in premature infants.

Nutritional status parameters, including body weight and oral feeding, are key in determining whether the premature infants can be discharged in time. At present, many reports on the application of human milk odor stimulation to improve the nutritional status of premature infants, but there are differences in the research results and a lack of comprehensive evaluation. Therefore, this systematic review and meta-analysis was conducted to comprehensively evaluate the effect of human milk odor stimulation, and to provide updated evidence for the development of nursing measures in clinical practice.

This study was conducted in conformity to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 15 .

Search strategy

Literature search was conducted from the establishment of the database to July 2022. We searched PubMed/Medline, Cochrane, Library, Embase, Web of science , Chinese biomedical literature databases, China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP ), and Wanfang Data Knowledge Service Platform to retrieve published studies on the human milk odor stimulation as an intervention to improve nutritional status in premature infants. Keyword selection and search included both medical subject headings (MeSH) and life science term indexes (EMBASE TREE; EMTREE). The relevant retrieval strategy was as follows: (“Infant newborn” OR “infant” OR “newborn” OR “neonate”) AND (“Feeding” OR “nutrition” OR “feed” OR “nourishment” OR “pabulum”) AND (“Olfactory stimulation” OR “breast milk stimulation” OR “olfactory” OR “human milk” OR “breast milk” OR “odorant” OR “odor” OR “odour” OR “smell”).

Inclusion criteria

Study characteristics used as criteria for eligibility are as follows: (1) Premature infants born at less than 37 weeks gestation who are receiving tube feeding and/or parenteral nutrition; (2) randomized controlled trials; (3) both groups of premature infants were given tube feeding and/or parenteral nutrition, with interventions involving the application of human milk odor stimulation in the intervention group and routine care in the control group; (4) evaluation metrics included transition time to oral feeding, length of stay, duration of parenteral nutrition, and/or body weight; (5) English or Chinese.

Exclusion criteria

(1) Duplicate articles; (2) Preclinical study, meta-analysis, case reports, reviews, guidelines; (3) Valid ending data unable to be extracted or calculated; (4) Full text of the study is not available; (5) The quality evaluation is grade C.

Data extraction

Two authors (YW and AP) carried out the data extraction process independently. Any disagreement was resolved with a senior researcher (CS) through discussion and consensus. Extracted contents were listed as follows: (1) Basic information of the included articles (title, the first author’s name, year of publication, geographic locations, the quality of the studies). (2) Baseline characteristics of the subjects in the eligible literature. (3) Detail of interventions or exposure factors. (4) The outcome indicators and outcome measures of interest (MD and SMD with the corresponding 95% CI).

Quality assessment

The quality of the selected studies was evaluated by two investigators using a revised tool for assessing risk of bias in Review Manager software. According to the Cochrane intervention research system evaluation manual 5.1.0, the document authenticity evaluation standard is carried out 16 . It mainly includes five aspects of bias (selection bias, performance bias, detection bias, attrition bias, reporting bias), six evaluation items: the generation method of random sequence, the concealment of random scheme allocation, the blind method of subjects and interventions, the blind method of outcome evaluators, the integrity of outcome data (loss of follow-up), and the possibility of selective reporting of research results. The single evaluation item is divided into three grades: (1) “low risk of bias” when a low risk of bias was determined for all domains, (2) “high risk of bias” when high risk of bias was reached for at least one domain or the study judgment included some concerns in multiple domains, and (3) unclear risk of bias 17 . The final quality evaluation grades of the literature are Grade A, grade B and grade C.

Statistical analysis

The main statistical software used in this study was ReviewManager5.3; Cochrane library) software. Measures such as length of hospital stay, duration of transitional oral feeding, and duration of parenteral nutrition use were statistically analyzed using the mean ± standard deviation and 95% CI. Standardized conversions could be performed with different measurement instruments to calculate MD/SMD values and 95% CI. The heterogeneity of included studies was examined by the I 2 index. If the test showed a high level of heterogeneity ( I 2  > 50%), a random effect model was used, otherwise a fixed-effect model ( I 2  < 50%) was used 18 . Sensitivity analysis was also performed to investigate the potential interference to the pooled effect size 19 . Statistical significance was set at P  < 0 0.05.

Ethics approval and consent to participate

This is a systematic review, no ethics review.

Literature search results

Initially, 322 literatures related to olfactory stimulation applied to premature infant were searched until July 28, 2022, of which 145 literatures related to human milk odor feeding of premature infants were screened. After excluding duplicate publications and those without full texts, 49 studies remained for full text screening. Reading through the full text, 26 articles were finally retained after excluding the inconsistent literature from the three aspects of study topic, overall design, and evaluation index. Then 12 articles were assessed for eligibility, and six randomized controlled studies were eventually included in the meta-analysis 20 , 21 , 22 , 23 , 24 , 25 (Fig.  1 ). General information and characteristics of the included literature are detailed (Table 1 ).

PRISMA flow diagram.

Quality assessment of the selected studies

The qualities of the six included literatures were evaluated as Grade B (partially meeting all criteria). Most of the studies failed to demonstrate the concealment of random scheme allocation and the blind method of outcome evaluators (Fig.  2 , Table 2 ).

Risk of bias assessment.

Effects of human milk odor stimulation on the transition time of oral feeding in premature infants

Five studies 20 , 21 , 22 , 23 , 24 evaluated the transition time of oral feeding for premature infants. Due to the small heterogeneity among studies ( P  = 0.39, I 2  = 3%), fixed-effect model analysis was conducted. The result showed that the transition time of oral feeding for premature infants in the intervention group was statistically significantly shorter than that in the routine care group,the statistical unit of the outcomes were days [SMD = − 0.48, 95% CI (− 0.69, − 0.27), Z = 4.54, P  < 0.00001] (Fig.  3 ).

Effects of human milk odor stimulation on the transition time of oral feeding for premature infants.

Effects of human milk odor stimulation on duration of parenteral nutrition in premature infants

Two studies 24 , 25 evaluated the duration of parenteral nutrition of premature infants. Due to the small heterogeneity among studies ( P  = 0.43, I 2  = 0%), the fixed effect model was used to analyze the duration of parenteral nutrition. The result indicated a statistically significantly shorter duration of parenteral nutrition support in the intervention group than that in the routine care group, the statistical unit of the outcomes were days [MD = − 1.01, 95% CI (− 1.70, − 0.32), Z = 2.88, P  = 0.004] (Fig.  4 ).

Effect of human milk odor stimulation on duration of parenteral nutrition for the premature infants.

Effects of human milk odor stimulation on the length of hospital stay for premature infants

Four 20 , 21 , 24 , 25 studies explored the impact of human milk odor stimulation intervention on the length of hospital stay. Random-effect model was applied given the high heterogeneity ( P  = 0.04, I 2  = 65%), which found no statistically significant difference between the intervention group and routine nursing care group [MD = − 0.28, 95% CI (− 1.19, 0.63), Z = 0.06, P  = 0.55] (Fig.  5 A). To explore the source of heterogeneity, sensitivity analysis was conducted by omitting one study at a time, which found that the study conducted by Yildiz could be have a significant impact the heterogeneity 20 . After removing this study 20 , heterogeneity was dramatically reduced ( P  = 0.50, I 2  = 0%), and fixed effect model was used to assess the effect of human milk odor stimulation intervention on the length of hospital stay. The result still showed no statistically significant difference between the two groups, the statistical unit of the outcomes were days [MD = − 0.03, 95% CI (− 0.41, 0.35), Z = 0.17, P  = 0.86] (Fig.  5 B).

( A ) Effects of human milk odor stimulation on the hospitalization time for premature infants before removing Yildiz’s study; ( B ) Effects of human milk odor stimulation on the hospitalization time for premature infants after removing Yildiz’s study.

The systematic review and meta-analysis of six randomized controlled studies found improved outcomes of premature infants associated with human milk odor stimulation. Premature infants are difficult to be fed through bottles by mouth due to underdeveloped oral motor function and uncoordinated sucking, swallowing and respiratory movements, which usually require formula or human milk delivered through a gastric tube 26 . In addition, oral exercise by oral intake contributes to weight gain and neurological development and accelerate their recovery process, while non-oral feeding deprives premature infants of oral exercise 27 , 28 , 29 . Moreover, prolonged tube feeding affects the oral motor skills of the child, leading to reduced respiratory coordination, late sensory problems, and malnutrition 30 . Malnutrition leads to lack of stable weight gain, prolonged hospitalization, and even neurological deficits and readmission 31 . In contrast, adequate nutrition, maintenance of weight gain, and physiological stability play crucial roles in the successful recovery of premature infants from hospitalization 22 . Therefore, the transition from parenteral or tube feeding to complete oral feeding will contribute significantly to sufficient nutrition and prompt recovery of premature infants. The results of the pooled analyses in the present study showed that human milk odor stimulation was able to reduce the time required for transition to normal oral feeding in premature infants. It is well known that normal oral feeding (sucking, swallowing and respiratory coordination) is an early sign of neuromotor integrity in premature infants and an important indication for hospital discharge 28 .

Premature infants admitted to the newborn intensive care unit (NICU) for further treatment and care after birth often require controlled number, frequency, and volume of feedings. Therefore, these newborns may lack adequate stimulation and sensory experiences related to feeding, such as hunger, fullness, taste, and smell 32 . Olfactory and gustatory stimulation alone or in combination can reduce gastrointestinal-related adverse reactions and effectively improve the nutritional status of premature infants by activating complex pathways and triggering cephalic responses, which increase intestinal motility, digestive enzyme secretion, and hormone release 33 , 34 , 35 . Therefore, the application of human milk odor stimulation plays a vital role in promoting the recovery process of premature infants.

Although human milk odor stimulation was associated with reduced transition time to oral feeding and short duration of parental feeding, it did not change the length of hospitalization. Hospitalization in premature infants is affected by a variety of confounding factors, such as body weight, gestational age, the occurrence of complications, family economic status, and medical environment factors. Relevant reports found that very low birth weight infants had significantly longer hospital stays. Moreover, it also revealed that the smaller the gestational age was, the more likely it would be to have complications such as infection, cerebral hemorrhage, and pulmonary hemorrhage, thus prolonging the length of hospital stay 36 . Due to differences in medical and economic levels in different countries, there will also be inconsistencies in the length of hospitalization for premature infants 37 .

It is noteworthy that the study by Küçük 23 , Beker 25 , Khodagholi 21 , and Yildiz 20 reported the weight of premature infants at discharge, and the mean weight at discharge of the control group of these infants in the four studies was 1933.10 ± 90.50 g, 2913 ± 577 g, 1588.1 ± 84.4 g, and 1922.25 ± 230.82 g, respectively. In contrast, the mean weight of the intervention group at discharge were 1908.00 ± 87.86 g, 2986 ± 672 g, 1565.6 ± 93.6 g, and 1893.50 ± 189.04, respectively. However, the difference of the discharge weight between the intervention group and the control group in each study was not statistically significant. Because the initial weight of the premature infants at admission was different between the control group and the intervention group, a simple comparison of body weight at discharge did not yield enough information. Therefore, the effects of the weight of premature infants were not included and observed.

Several inherent limitations need to be noticed when interpreting the results of this meta-analysis. First, the number of studies included was small with overall small sample size. Second, all included studies had a quality rating of B, which may have had an impact on the evaluation results. Third, other parameters, such as weight gain in premature infants, were not available and their effects were not assessed.

This systematic review and meta-analysis found that human milk odor could reduce the transition time to oral feeding and duration of parenteral nutrition for premature infants, suggesting a cheap, effective, and easily accessible method to improve the overall outcomes of premature infants. However, the findings are limited by the number and quality of included studies, therefore, more well-designed studies are still needed to verify our findings.

Data availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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1. Henan Traditional Chinese Medicine Culture and management Research Projece (NO.TCM2023001); 2. Special Scientific Research Project of Traditional Chinese Medicine in Henan Province (NO.2022JDZX075) 3. Soft Science Projece of Medical Science and Technology Research Programme of Henan Province (NO.RKX202302026); 4. Special Research Project of National TCM Inheritance and Innovation Centre of Henan Provincial Health Commission (NO2023ZXZX1102); 5. Special Research Project of National TCM Inheritance and Innovation Centre of Henan Provincial Health Commission NO.2023ZXZX1114.

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Yangyang Qin, Shu Liu, Yanming Yang & Yuan Zhong

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Yangyang Qin and Shu Liu were responsible for the topic selection, literature search, draft of the paper and data analysis. Han Han participated in literature screening, literature quality evaluation, and made the final revision of the paper. All authors conducted the search of literature, reviewed the articles, helped with data synthesis and interpretation, and played a major role in writing the manuscript. All authors agree to publish.

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Qin, Y., Liu, S., Yang, Y. et al. Effects of human milk odor stimulation on feeding in premature infants: a systematic review and meta-analysis. Sci Rep 14 , 8964 (2024). https://doi.org/10.1038/s41598-024-59175-4

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Received : 15 September 2022

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DOI : https://doi.org/10.1038/s41598-024-59175-4

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