Article Text

Download PDFPDF

Examining the quality of evidence to support the effectiveness of interventions: an analysis of systematic reviews
  1. Robert L Kane1,
  2. Mary Butler1,
  3. Weiwen Ng2
  1. 1Minnesota Evidence-based Practice Center, University of Minnesota School of Public Health, Minneapolis, Minnesota, USA
  2. 2Health Services Research, Policy, and Administration, University of Minnesota School of Public Health, Minneapolis, Minnesota, USA
  1. Correspondence to Professor Robert L Kane; kanex001{at}


Objective This analysis examines the quality of evidence (QOE) for 1472 outcomes linked to interventions where the QOE was rated in 42 systematic reviews of randomised clinical trials and/or observational studies across different topics.

Setting Not applicable.

Participants 76 systematic reviews.

Primary and secondary outcome measures Strength of evidence ratings by initial reviewers.

Results Among 76 systematic reviews, QOE ratings were available for only 42, netting 1472 comparisons. Of these, 57% included observational studies; 4% were rated as high and 12% as moderate; the rest were low or insufficient. The ratings varied by topic: 74% of the surgical study pairs were rated as low or insufficient, compared with 82% of pharmaceuticals and 86% of device studies, 88% of organisational, 91% of lifestyle studies, and 94% of psychosocial interventions.

Conclusions We are some distance from being able to claim evidence-based practice. The press for individual-level data will make this challenge even harder.

  • Evidence based practice
  • Policy
  • Care decisions

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.