A systematic review attempts to collate all empirical evidence that fits pre-specified eligibility criteria in order to answer a specific research question. The key characteristics of a systematic review are: a clearly defined question with inclusion & exclusion criteria; rigorous & systematic search of the literature; critical appraisal of included studies; data extraction and management; analysis & interpretation of results; and report for publication.
A systematic review attempts 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. (See Section 1.2 in the Cochrane Handbook for Systematic Reviews of Interventions.)
Time: On average, systematic reviews require 18 months of preparation.
A team: A systematic review can't be done alone! You need to work with subject experts to clarify issues related to the topic; librarians to develop comprehensive search strategies and identify appropriate databases; reviewers to screen abstracts and read the full text; a statistician who can assist with data analysis; and a project leader to coordinate and write the final report.
A clearly defined question: Clarify the key question(s) of you systematic review and the rationale for each question. Use the PICO framework to identify key concepts of the question. Determine inclusion/exclusion criteria.
A written protocol: You need to write a protocol outlining the study methodology. The protocol should include the rationale for the systematic review, key questions broken into PICO components, inclusion/exclusion criteria, literature searches for published/unpublished literature, data abstraction/data management, assessment of methodological quality of individual studies, data synthesis, and grading the evidence for each key question.
Need help writing a protocol? See the University of Warwick's protocol template.
A registered protocol: After you write the protocol, you should register it with PROSPERO, an International Prospective Register of Systematic Reviews. Registration is free and open to anyone undertaking systematic reviews of the effects of interventions and strategies to prevent, diagnose, treat, and monitor health conditions, for which there is a health related outcome.
For more information about registering protocols & PROSPERO, see:
Best practices in systematic reviews: the importance of protocols & registration
An international registry of systematic review protocols
Comprehensive literature searches: First, identify systematic reviews that may address your key questions. Then, identify appropriate databases and conduct comprehensive and detailed literature searches that can be documented and duplicated.
Citation management: You should have working knowledge of EndNote to help manage citations retrieved from literature searches.
Follow reporting guidelines: Use appropriate guidelines for reporting your review for publication.
For more information about the nuances of conducting systematic reviews, contact your Medical Librarian!