Perspective
1 January 1992

A Consumer's Guide to Subgroup Analyses

Publication: Annals of Internal Medicine
Volume 116, Number 1

Abstract

▪ The extent to which a clinician should believe and act on the results of subgroup analyses of data from randomized trials or meta-analyses is controversial. Guidelines are provided in this paper for making these decisions. The strength of inference regarding a proposed difference in treatment effect among subgroups is dependent on the magnitude of the difference, the statistical significance of the difference, whether the hypothesis preceded or followed the analysis, whether the subgroup analysis was one of a small number of hypotheses tested, whether the difference was suggested by comparisons within or between studies, the consistency of the difference, and the existence of indirect evidence that supports the difference. Application of these guidelines will assist clinicians in making decisions regarding whether to base a treatment decision on overall results or on the results of a subgroup analysis.

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Published In

cover image Annals of Internal Medicine
Annals of Internal Medicine
Volume 116Number 11 January 1992
Pages: 78 - 84

History

Published in issue: 1 January 1992
Published online: 1 December 2008

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From McMaster University Health Sciences Centre, Hamilton, Ontario. For current author addresses, see end of text.

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Andrew D. Oxman, Gordon H. Guyatt. A Consumer's Guide to Subgroup Analyses. Ann Intern Med.1992;116:78-84. doi:10.7326/0003-4819-116-1-78

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