LibGuides: ATSU Library Research Hub: Literature Reviews

Overview of a Literature Review

A literature review is a generic term used to describe a synthesis of information to answer a research question. The purpose of a literature review is to present the scholarly information that is available on a topic, provide support to the proposed research, and relate the literature to the proposed research question. There are numerous types of literature reviews. These vary from a narrative review to a systematic review.

Review types differ by

the precision of the research question (broad to specific)
the goal of the review
the standards of the searching method
if the articles are appraised
how information from various sources is synthesized
the analysis of the results
showing the current state of the literature around a particular topic

Various Review Types

Review Type	Definition	Search methods	Appraisal	Synthesis	Analysis
Literature or Narrative Review (May be completed by a single author)	Generic term: A synthesis of current literature surrounding a specific topic. The purpose of a narrative review is to provide background information on the topic, support the proposed research and/or answer a research question.	Non-specific; Author chooses relevant articles based on research question.	Determined by the author	Narrative	Chronological, conceptual, thematic, etc.
Scoping/Mapping Review (Requires a minimum of 2 authors)	Preliminary assessment of potential size and scope of available research literature on a broad topic. Aims to identify nature and extent of research evidence. Includes grey literature, preprints and ongoing studies. Scoping reviews are conducted based upon the JBI manual of evidence synthesis.	Broad scope of literature available. Search methods must be transparent and reproducible. Search strategies are peer reviewed & documented in full.	All evidence is independently screened by 2 reviewers to ensure evidence meets the inclusion criteria. The critical appraisal process is optional but recommended	Narrative	Characterizes quantity and quality of literature based upon the elements of the PCC research question and the inclusion/exclusion criteria
Systematic Review (Requires a minimum of 2 authors)	Seeks to systematically search for, appraise and synthesize all available research evidence on the topic. SRs answer a specific research question and are conducted based upon the JBI manual of evidence synthesis.	Exhaustive, comprehensive, & systematic search. Search methods must be transparent & reproducible. Search strategies are peer reviewed & well documented.	All evidence is independently screened by 2 reviewers to meet inclusion criteria and critically appraised using the JBI Critical Appraisal Checklists	Narrative	Synthesizes what is known within the existing literature. Highlights what is unknown, and recommends future research.
Umbrella Review (Requires a minimum of 2 authors)	Reviews the results of multiple systematic reviews on a specific topic. All reviews must analyze a shared methodology, facilitating comparison and analysis. Umbrella reviews are conducted based upon the JBI manual of evidence synthesis	Exhaustive, comprehensive & systematic search of reviews. Does not include primary studies. Search methods must be transparent, reproducible and well documented.	All evidence is independently screened by 2 reviewers to meet inclusion criteria and critically appraised using the JBI Critical Appraisal Checklists	Graphical and tabular with narrative commentary	What is known; Recommendations for practice. What remains unknown; recommendations for future research
Rapid Review (Requires a minimum of 2 authors)	Assessment of what is already known about a policy or practice issue, by using systematic review methods to search and critically appraise existing research. RRs are conducted according to the JBI manual of evidence synthesis	Completeness of searching determined by time constraints. All search strategies must be transparent, reproducible and documented.	Time-limited formal quality assessment. All evidence is independently screened by 2 reviewers to meet inclusion criteria	Narrative and tabular	Quantities of literature and overall quality/direction of effect of literature
Meta-analysis	Statistical analysis of quantitative evidence provided within a Systematic Review. Meta-analysis are conducted according to the JBI manual of evidence synthesis	Exhaustive, comprehensive & systematic search of reviews. Does not include primary studies. Search methods must be transparent, reproducible and documented.	All evidence has been critically appraised in the systematic review	Graphical representation in a Forest plot.	Numerical analysis of measures of effect assuming absence of heterogeneity

Reproduced from Grant, M. J. and Booth, A. (2009), A typology of reviews: an analysis of 14 review types and associated methodologies. Health Information & Libraries Journal, 26: 91–108. doi:10.1111/j.1471-1842.2009.00848.x

What is a Narrative Review?

A narrative literature review is an integrated analysis of the existing literature used to summarize a body of literature, draw conclusions about a topic, and identify research gaps. By understanding the current state of the literature, you can show how new research fits into the larger research landscape.

A Literature Review is NOT:

Just a summary of sources
A review of everything written on a particular topic
A research paper arguing for a specific viewpoint - a lit review should avoid bias and highlight areas of disagreements
A systematic review

Purposes of a Literature Review

Explain the background of research on a topic
Demonstrate the importance of a topic
Suggest new areas of research
Identify major themes, concepts, and researchers in a topic
Identify critical gaps, points of disagreement, or flawed approaches for a research topic

Literature Review Process

1. Choose a topic & create a research question

Use a narrow research question for more focused search results
Use a question framework such as PICO to develop your research question
Break down your research question into searchable concepts and keywords
See our Developing a Research Topic LibGuide for more information, or ask your liaison librarian for help

2. Select the sources for searching & develop a search strategy

Identify databases to search for articles in
Reach out to your liaison librarian for recommended databases for your research topic
Develop a comprehensive search strategy using keywords, controlled vocabularies, and Boolean operators.
See the Developing a Search Strategy page for more information. Reach out to a librarian if you have any questions.

3. Conduct the search

Use a consistent search strategy, keeping it as similar as possible between the different databases you use
Reach out to your liaison librarian for assistance translating searches between databases
Use a citation manager to organize your search results

4. Review the references

Review each reference and remove articles that are not relevant to your research question
Take notes on each reference you keep. Consider using an excel spreadsheet or other standardized way of summarizing information from each article
Use Interlibrary Loan for any articles without full-text access

5. Summarize Findings

Synthesize the findings from the articles you reviewed into a final paper
The paper should cover the themes identified in the research, explain any conflicts or disagreements in the research, identify research gaps and potential future research areas, and explain the importance of the research topic.
Use Sage Research Methods to learn more about writing a literature review

Library Support

Your liaison librarian can assist you in conducting a literature review by

Conducting literature searches on your behalf
Evaluating and improving your search strategy
Helping with citation management tools
Helping you refine your research question and choose the best type of review