A review and re-interpretation of a group-sequential approach to sample size re-estimation in two-stage trials.
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ABSTRACT:
SUBMITTER: Bowden J
PROVIDER: S-EPMC4288989 | biostudies-literature | 2014 May-Jun
REPOSITORIES: biostudies-literature
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A review and re-interpretation of a group-sequential approach to sample size re-estimation in two-stage trials.
Pharmaceutical statistics 20140402 3
In this paper, we review the adaptive design methodology of Li et al. (Biostatistics 3:277-287) for two-stage trials with mid-trial sample size adjustment. We argue that it is closer in principle to a group sequential design, in spite of its obvious adaptive element. Several extensions are proposed that aim to make it even more attractive and transparent alternative to a standard (fixed sample size) trial for funding bodies to consider. These enable a cap to be put on the maximum sample size and ...[more]
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