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Methodological criteria for the assessment of moderators in systematic reviews of randomised controlled trials : a consensus study

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Pincus, Tamar, Miles, Clare, Froud, Robert J., Underwood, M. (Martin) M.D., Carnes, Dawn and Taylor, Stephanie J. C.. (2011) Methodological criteria for the assessment of moderators in systematic reviews of randomised controlled trials : a consensus study. BMC Medical Research Methodology, Vol.11 . Article:14. ISSN 1471-2288

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Official URL: http://dx.doi.org/10.1186/1471-2288-11-14

Abstract

Background: Current methodological guidelines provide advice about the assessment of sub-group analysis within
RCTs, but do not specify explicit criteria for assessment. Our objective was to provide researchers with a set of
criteria that will facilitate the grading of evidence for moderators, in systematic reviews.
Method: We developed a set of criteria from methodological manuscripts (n = 18) using snowballing technique,
and electronic database searches. Criteria were reviewed by an international Delphi panel (n = 21), comprising
authors who have published methodological papers in this area, and researchers who have been active in the
study of sub-group analysis in RCTs. We used the Research ANd Development/University of California Los Angeles
appropriateness method to assess consensus on the quantitative data. Free responses were coded for consensus
and disagreement. In a subsequent round additional criteria were extracted from the Cochrane Reviewers’
Handbook, and the process was repeated.
Results: The recommendations are that meta-analysts report both confirmatory and exploratory findings for subgroups
analysis. Confirmatory findings must only come from studies in which a specific theory/evidence based apriori
statement is made. Exploratory findings may be used to inform future/subsequent trials. However, for
inclusion in the meta-analysis of moderators, the following additional criteria should be applied to each study:
Baseline factors should be measured prior to randomisation, measurement of baseline factors should be of
adequate reliability and validity, and a specific test of the interaction between baseline factors and interventions
must be presented.
Conclusions: There is consensus from a group of 21 international experts that methodological criteria to assess
moderators within systematic reviews of RCTs is both timely and necessary. The consensus from the experts
resulted in five criteria divided into two groups when synthesising evidence: confirmatory findings to support
hypotheses about moderators and exploratory findings to inform future research. These recommendations are
discussed in reference to previous recommendations for evaluating and reporting moderator studies.

Item Type:	Journal Article
Subjects:	R Medicine > R Medicine (General)
Divisions:	Faculty of Medicine > Warwick Medical School > Health Sciences Faculty of Medicine > Warwick Medical School
Library of Congress Subject Headings (LCSH):	Clinical trials, Systematic reviews (Medical research) -- Methodology
Journal or Publication Title:	BMC Medical Research Methodology
Publisher:	BioMed Central Ltd.
ISSN:	1471-2288
Official Date:	31 January 2011
Volume:	Vol.11
Page Range:	Article:14
Identification Number:	10.1186/1471-2288-11-14
Status:	Peer Reviewed
Publication Status:	Published
Access rights to Published version:	Open Access
Funder:	National Institute for Health Research (Great Britain) (NIHR), Advantage West Midlands (AWM), Birmingham Science City
Grant number:	RP-PG-0707-10189 (NIHR)
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URI:	http://wrap.warwick.ac.uk/id/eprint/34575