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Open Access 01-04-2011 | COMMENTARY

The (mis)use of overlap of confidence intervals to assess effect modification

Authors: Mirjam J. Knol, Wiebe R. Pestman, Diederick E. Grobbee

Published in: European Journal of Epidemiology | Issue 4/2011

Excerpt

In randomized controlled trials as well as in observational studies, researchers are often interested in effects of treatment or exposure in different subgroups, i.e. effect modification [1, 2]. There are several methods to assess effect modification and the debate on which method is best is still ongoing [2‐5]. In this article we focus on an invalid method to assess effect modification, which is often used in articles in health sciences journals [6], namely concluding that there is no effect modification if the confidence intervals of the subgroups are overlapping [7‐9]. …

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Title: The (mis)use of overlap of confidence intervals to assess effect modification
Authors: Mirjam J. Knol
Wiebe R. Pestman
Diederick E. Grobbee
Publication date: 01-04-2011
Publisher: Springer Netherlands
Published in: European Journal of Epidemiology / Issue 4/2011
Print ISSN: 0393-2990
Electronic ISSN: 1573-7284
DOI: https://doi.org/10.1007/s10654-011-9563-8

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The (mis)use of overlap of confidence intervals to assess effect modification

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