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Published in: Trials 1/2016

Open Access 01-12-2016 | Commentary

Risk of selection bias in randomized trials: further insight

Author: Vance W. Berger

Published in: Trials | Issue 1/2016

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Abstract

The quality of randomization is an under-appreciated facet of trial design. The present piece represents an advance in our collective understanding of how allocation concealment and randomization relate to risk of selection bias in randomized trials, and other measures are also considered. Though the overwhelming majority of the advice given is timely and correct, it is more instructive to focus on the relatively narrow sliver of advice that is incorrect (namely, that trials should not stratify by site, and that unrestricted randomization is a solution to the problem of selection bias), so it is in this context that the comments here must be understood. In no way is this intended to be a rebuttal of the excellent work we have before us. Rather, it is a refinement.
Literature
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Berger VW, Do AC. Allocation concealment continues to be misunderstood. J Clin Epidemiol. 2010;63(4):468–70.CrossRefPubMed
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Metadata
Title
Risk of selection bias in randomized trials: further insight
Author
Vance W. Berger
Publication date
01-12-2016
Publisher
BioMed Central
Published in
Trials / Issue 1/2016
Electronic ISSN: 1745-6215
DOI
https://doi.org/10.1186/s13063-016-1597-5

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