Skip to Main Content

Reviews and Evidence Syntheses: Systematic Reviews & Meta-Analyses

Definition

"A systematic review attempts to collate all empirical evidence that fits pre-specified eligibility criteria in order to answer a specific research question.  It  uses explicit, systematic methods that are selected with a view to minimizing bias, thus providing more reliable findings from which conclusions can be drawn and decisions made. [...] Many systematic reviews contain meta-analyses. Meta-analysis is the use of statistical methods to summarize the results of independent studies. By combining information from all relevant studies, meta-analyses can provide more precise estimates of the effects of health care than those derived from the individual studies included within a review. They also facilitate investigations of the consistency of evidence across studies, and the exploration of differences across studies."

Goal | Purpose | Key Features

Key characteristics of a systematic review:

  • a clearly stated set of objectives with pre-defined eligibility criteria for studies;
  • an explicit, reproducible methodology;
  • a systematic search that attempts to identify all studies that would meet the eligibility criteria;
  • an assessment of the validity of the findings of the included studies, for example through the assessment of risk of bias; and
  • a systematic presentation, and synthesis, of the characteristics and findings of the included studies.
  • Meta-analysis (when included) is the use of statistical methods to summarize the results of independent studies

Key Steps in the Process:

Conducting a systematic review is a multi-step and planned process.  This is part of the 'systematic' nature of this type of publication.

 

What Authors do in Systematic Reviews

 

Designed by Jessica Kaufman, Cochrane Consumers & Communication Review Group, Centre for Health Communication & Participation, La Trobe University, 2011. CC-BY-SA License

The Systematic Review Team

Each step in the process may involve careful planning and documentation and required diverse skills and knowledge. Therefore, an entire team of professionals will work together to produce a systematic review.  The systematic review team typically consists of the following members (at minimum):

  • Content experts in the area of the research question being investigated
    • 2 screeners (for both screening and data extraction)
    • 1 tie breaker (for when the screeners disagree on whether an item meets the inclusion/exclusion criteria)
  • 1 statistician (meta-analysis)
  • 1 or more information professional or proficient searcher of medical literature databases

More details on the process are discussed in the Systematic Reviews libguide.

Guidance

Guidance on How to Conduct Systematic Reviews (and Meta Analyses)

Guidance on how to Write Up a Systematic Review or Meta Analyses (Reporting Guidelines and Checklists)

Exemplar Systematic Reviews

Librarian Support

How can University of Toledo librarians help with your systematic review or meta-analysis?

  • For faculty, resident physicians, fellows, and staff members: a librarian can meet with you and/or members of your research team to discuss your systematic review protocol, including talking about your topic and recommending search strategies, as well as databases and search terms that would be appropriate for your topic.
    • Prior to this consultation, you will want to identify if there are existing forthcoming or recently published systematic reviews, and fill out and return the Systematic Review Consultation Request intake form.  Much of the work on this form will also be useful for registering your systematic review protocol. No systemtic review consultation can be scheduled if not accompanied by a completed intake form.
    • Form should be submitted as an attachment to an e-mail to MulfordReference@utoledo.edu.
    • You will be contacted by a Health Science Librarian to schedule your consult at a mutually agreeable time.
    • After the consultation, you and your team will be responsible for developing and running searches in multiple databases, documenting your search strategies and the results, maintaining your own team's records and collections of articles retrieved.
  • For students: If you are part of a systematic review team, please have one of the team members who is a faculty member, resident, fellow, or staff member initiate the process.

Note: Our services are only available to current UToledo faculty, resident physicians, fellows, and staff members. If you are affiliated with another institution, please contact your library to see what services are available for your review.