"A comprehensive review uses literature review methods that are specific and thorough to avoid outcome bias. A valid comprehensive review is a systematic, scientifically designed review of a defined literature base that employs the rigor of original research in an effort to limit outcome bias." (Stratton, 2016)
Comprehensive reviews require exhaustive searches of the literature and detailed documentation of literature search methods. These literature searches require a much greater time investment compared to searches for non comprehensive reviews.
| Comprehensive Reviews | Non Comprehensive Reviews |
| Systematic Reviews | Narrative Reviews |
| Scoping Reviews | Critical Reviews |
| Umbrella Reviews | |
| Integrative Reviews | |
| Rapid Reviews |
What is a Systematic Review?
"A systematic review is a review of a clearly formulated question that uses systematic and explicit methods to identify, select, and critically appraise relevant research, and to collect and analyze data from the studies that are included in the review.
Statistical methods (meta-analysis) may or may not be used to analyze and summarize the results of the included studies. Meta-analysis refers to the use of statistical techniques in a systematic review to integrate the results of included studies." - Definition from the PRISMA Statement, adopted from the Cochrane Collaboration
One way that a systematic review differs from other review methodologies is that systematic reviews are protocol driven. Similar to how one would not embark on primary research without a research protocol, one should have a protocol in place before initiating a systematic review.
For more information about what constitutes a systematic review: Munn, Z., Stern, C., Aromataris, E. et al. What kind of systematic review should I conduct? A proposed typology and guidance for systematic reviewers in the medical and health sciences. BMC Med Res Methodol 18, 5 (2018) doi:10.1186/s12874-017-0468-4
Unsure what type of review methodology to use? Try the "Which Review Is Right For You?" tool.
Treadwell librarians offer two tiers of comprehensive review service.
Due to the in-depth and time-intensive nature of this work, each librarian can work on a limited number of comprehensive reviews at a time so the service may not be available if we have already reached our maximum capacity.
As projects evolve individual librarians retain the right to change tiers to accurately reflect the nature of the work being conducted, as well as refuse co-authorship.
For biostatistics consultations, contact the MGH Division of Clinical Research or the Harvard Catalyst Biostatistics Consultation Service.
Ask Us! if:
To arrange a consultation:
1) Download and fill out the preconsultation form below.
2) Send us an online Ask Us! message to request a time for a consultation and attach the completed form to your message.
3) We will review your request and contact you to arrange a time for a virtual consultation.
Learn how to conduct systematic reviews in our Systematic Review Process and Systematic Review Standards pages.
Resources about other common comprehensive review methodologies are listed below.
Scoping Reviews
Systematic Reviews of Reviews/Umbrella Reviews
Rapid Reviews
Rapid reviews omit parts of the systematic review process to speed up the review process.
Integrative Reviews
Integrative reviews are most often seen in the nursing discipline.
Living Systematic Reviews
Living systematic reviews are continually updated reviews that may be used to synthesize rapidly evolving areas of research.
Treadwell provides access to Covidence, an online platform that aims to accelerate the systematic review process, at no cost to MGH employees. MGH employees can also invite individuals from outside of MGH to collaborate on systematic reviews at no cost.
Covidence is accessible by computer or mobile device, and provides one convenient place to screen citations, assess risk of bias, and extract data.
Access Covidence
To access Covidence, request an invitation here using your mgh.harvard.edu or mghihp.edu e-mail address. Do not use your partners.org address.
Have a MGH Covidence account already? Log in here.
Learn How to Get Started With Covidence
For videos and written instructions to help you get started with Covidence, see our support page in the Covidence Knowledge Base.
