Not to be confused with a book review, a literature review surveys scholarly articles, books and other sources (e.g. dissertations, conference proceedings) relevant to a particular issue, area of research, or theory, providing a description, summary, and critical evaluation of each work. The purpose is to offer a narrative or overview of significant literature published on a topic. There are various types of literature reviews, below are the most common.
The Cochrane Handbook for Systematic Reviews of Interventions which defines a systematic review (Section 1.2) as:
"...an attempt to identify, appraise and synthesize all the empirical evidence that meets pre-specified eligibility criteria to answer a given research question. Researchers conducting systematic reviews use explicit methods aimed at minimizing bias, in order to produce more reliable findings that can be used to inform decision making."
Want to put your knowledge to the test? Take the library's online tutorial, Getting Started with Literature Reviews. It takes about 20 minutes to complete and will give provide a printable certificate of completion at the end.
By the end of the tutorial, you will be able to:
A literature review summarizes broad topic (ex: water pollution) using qualitative (narrative) methods by incorporating a variety of sources. It may be assigned as a stand-alone project for a class where you are asked to examine literature or sources around a specific; or part of a larger body of work such as a thesis or dissertation where you examine literature and how it connects to your research. It is commonly used across all disciplines, for all levels of scholarship (undergrad, graduate and professional).
A systematic literature review answers a specific question (ex: Are micro plastics in drinking water a contributing factor for an increase in cancer in urban populations?) through a structured format such as PICO or PRISMA. It will demonstrate your search strategy along with information about what was included/excluded and why. It is highly technical, and may be used by graduate students, experts and professionals across all disciplines.
A meta-analysis literature review looks at studies from a systematic review, combining the studies in order to collect data and get a statistically relevant result. This type of review is helpful in using statistical analysis to examine or overturn results from smaller clinical trials. It is highly technical, and typically used by experts and professionals in medical fields.
A mapping/scoping review seeks to provide an overview of the available research evidence without producing a summary answer to a discrete research question. It is a newer method of literature review analysis and is used across all disciplines, but more specifically in medical sciences.
A comprehensive literature review helps you build a case for your own research and helps you base your research on a strong scholarly foundation. You will need to review the materials you have collected and the feedback received by your cohort. Then, identify any gaps in your research. Conduct and in-depth literature review using bibliographies and references lists from sources you have already collected. Use tools like Web of Science to track highly cited/landmark articles and to find related articles. Search using Library Search, databases, theses and dissertations, and more.
An umbrella review compares and contrasts the findings of previous reviews relevant to a review question. An umbrella review synthesizes only the highest level of evidence - other systematic reviews and meta-analyses.
A rapid review speeds up the systematic review process by omitting some stages of the systematic review. While less rigorous, rapid reviews provide more timely information for clinical decision making compared with standard systematic reviews.
* Used in undergraduate, graduate and professional work
* Commonly used in graduate and professional work
|Provides an overview of a topic
|Examines a clearly defined topic or question
|Does not use an explicit search protocol or plan
|Uses an explicit search plan or protocol to minimize bias
|The search process may or may not include all potentially relevant studies
|A comprehensive search is undertaken to identify all potentially relevant studies
|An explicit, predetermined protocol is not used to select the studies that are used to support the reviewers' recommendations
|An explicit, predetermined protocol, that specifies inclusion and exclusion criteria, is used to select studies for the review
|A level of evidence rating system may be used to "grade" the quality and strength of individual studies
|The quality of individual studies is rigorously appraised in a meta-analysis and a systematic synthesis of the results of included studies is undertaken with evidence "grades" applied to individual studies
|May be evidence-based, but is not evidence (research)
|Provides evidence (research)
|When evidence is lacking, the authors make recommendations based on their opinions and experience
|When evidence is lacking, the authors usually recommend further research