**PLEASE NOTE**
The process of conducting a formal systematic review project is long and involved, typically ranging from 1 to 3 years to complete. Systematic reviews also require a research cohort of two or more members.
A systematic review is only one of several evidence synthesis review types. For a summary of each main type, please see the box below on this page.
Faculty, researchers and graduate students affiliated with the CWRU School of Medicine or School of Nursing can get help with conducting systematic reviews by first contacting the CWRU Cleveland Health Sciences Library.
Faculty, researchers and graduate students affiliated with the CWRU Mandel School of Applied Social Sciences can get help with conducting evidence synthesis reviews by first contacting the CWRU MSASS library.
Faculty, researchers and graduate students affiliated with the CWRU College of Arts & Science can get help with conducting evidence synthesis reviews by first contacting the CWRU Kelvin Smith Library.
The Cochrane Library, the most prominent database of systematic reviews in medicine, defines the systematic review as the "[Attempt] to identify, appraise and synthesize all the empirical evidence that meets pre-specified eligibility criteria to answer a specific research question. Researchers conducting systematic reviews use explicit, systematic methods that are selected with a view aimed at minimizing bias, to produce more reliable findings to inform decision making."
Systematic reviews are a structured, comprehensive approach to finding, evaluating, and synthesizing the literature on a topic. The goal is to eliminate bias in the search and selection process and to include as much high-quality literature on a topic as possible, both published and unpublished. The process of searching for and selecting literature is thoroughly documented, and should be included in the final version of the review. The systematic review process developed in the medical and health sciences, but it is also sometimes used for review projects in the social sciences.
Literature Review: Literature reviews are similar to systematic reviews in that researchers provide a summary and synthesis of the extant literature on a topic. However, there is no formalized process for literature reviews; the scope of the search and search strategies will vary according to the needs of the researcher and no search protocol or inclusion-exclusion criteria need to be included in the final document. Literature reviews also typically do not include unpublished and gray literature as systematic reviews do. The advantage of a literature review is that it is much quicker and simpler to carry out than a systematic review. The disadvantage is that a literature review is less comprehensive and its selection process is vulnerable to bias. If you are an undergraduate researcher, you will likely only ever be expected to conduct a literature review.
Scoping Review: In a scoping review, researchers seek to find and categorize the research on a given topic. Like a systematic review it involves a rigorous, transparent search and selection process, but it does not synthesize the research. The topics explored in scoping reviews are often broader than those of systematic reviews, and the aim is to identify gaps in the current research on a topic rather than to answer a specific research question. The results of a scoping review can be used to identify topics for further research.
Rapid Review: Rapid reviews use the same methodology as a systematic review, but introduce some shortcuts in order to reduce the timeframe for completion. This can lead to some bias, but it is sometimes necessary for time-sensitive projects.
Umbrella Review: This is a review of systematic reviews. Umbrella reviews are useful for examining broader research questions than those of systematic reviews. In the medical context, for example, they might be useful for comparing alternative treatments for an illness in the same population.
Meta-analysis: A meta-analysis is a quantitative summary of the results of a set of studies. In a meta-analysis, researchers conduct a statistical analysis to compare the results of the included studies and identify overall trends. Systematic reviews may or may not include a meta-analysis as part of their synthesis of research.