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Do evidence summaries increase health policy-makers’ use of evidence from systematic reviews?

Additional Info

  • Authors: Jennifer Petkovic, Vivian Welch, Marie Helena Jacob, Manosila Yoganathan, Ana Patricia Ayala, Heather Cunningham, Peter Tugwell
  • Published date: 2018-09-10
  • Coordinating group(s): Knowledge Translation and Implementation
  • Type of document: Title, Protocol, Review, Plain language summary
  • See the full review:

About this systematic review

This review summarizes the evidence from six randomized controlled trials that judged the effectiveness of systematic review summaries on policymakers’ decision making, or the most effective ways to present evidence summaries to increase policymakers’ use of the evidence.

What are the main results?

Our review suggests that evidence summaries help policymakers to better understand the findings presented in systematic reviews. In short, evidence summaries should be developed to make it easier for policymakers to understand the evidence presented in systematic reviews. However, right now there is very little evidence on the best way to present systematic review evidence to policymakers.


Systematic reviews are important for decision makers. They offer many potential benefits but are often written in technical language, are too long, and do not contain contextual details which makes them hard to use for decision-making. Strategies to promote the use of evidence to decision makers are required, and evidence summaries have been suggested as a facilitator. Evidence summaries include policy briefs, briefing papers, briefing notes, evidence briefs, abstracts, summary of findings tables, and plain language summaries. There are many organizations developing and disseminating systematic review evidence summaries for different populations or subsets of decision makers. However, evidence on the usefulness and effectiveness of systematic review summaries is lacking. We present an overview of the available evidence on systematic review evidence summaries.


This systematic review aimed to 1) assess the effectiveness of evidence summaries on policy-makers’ use of the evidence and 2) identify the most effective summary components for increasing policy-makers’ use of the evidence.

Search methods

We searched several online databases (Medline, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, Global Health Library, Popline, Africa-wide, Public Affairs Information Services, Worldwide Political Science Abstracts, Web of Science, and DfiD), websites of research groups and organizations which produce evidence summaries, and reference lists of included summaries and related systematic reviews. These databases were searched in March-April, 2016.

Selection criteria

Eligible studies included randomised controlled trials (RCTs), non-randomised controlled trials (NRCTs), controlled before-after (CBA) studies, and interrupted time series (ITS) studies. We included studies of policymakers at all levels as well as health system managers. We included studies examining any type of “evidence summary”, “policy brief”, or other product derived from systematic reviews that presented evidence in a summarized form. These interventions could be compared to active comparators (e.g. other summary formats) or no intervention. The primary outcomes were: 1) use of systematic review summaries decision-making (e.g. self-reported use of the evidence in policy-making, decision-making) and 2) policymaker understanding, knowledge, and/or beliefs (e.g. changes in knowledge scores about the topic included in the summary). We also assessed perceived relevance, credibility, usefulness, understandability, and desirability (e.g. format) of the summaries.


Our database search combined with our grey literature search yielded 10,113 references after removal of duplicates. From these, 54 were reviewed in full text and we included 6 studies (reported in 7 papers, 1661 participants) as well as protocols from 2 ongoing studies. Two studies assessed the use of evidence summaries in decision-making and found little to no difference in effect. There was also little to no difference in effect for knowledge, understanding or beliefs (4 studies) and perceived usefulness or usability (3 studies). Summary of Findings tables and graded entry summaries were perceived as slightly easier to understand compared to complete systematic reviews. Two studies assessed formatting changes and found that for Summary of Findings tables, certain elements, such as reporting study event rates and absolute differences were preferred as well as avoiding the use of footnotes. No studies assessed adverse effects. The risks of bias in these studies were mainly assessed as unclear or low however, two studies were assessed as high risk of bias for incomplete outcome data due to very high rates of attrition.

Authors’ conclusions

Evidence summaries may be easier to understand than complete systematic reviews. However, their ability to increase the use of systematic review evidence in policymaking is unclear.

See the full review

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