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PubMed · 11315085

Adaptive sample size calculations in group sequential trials.

W Lehmacher·G Wassmer
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Abstract

A method for group sequential trials that is based on the inverse normal method for combining the results of the separate stages is proposed. Without exaggerating the Type I error rate, this method enables data-driven sample size reassessments during the course of the study. It uses the stopping boundaries of the classical group sequential tests. Furthermore, exact test procedures may be derived for a wide range of applications. The procedure is compared with the classical designs in terms of power and expected sample size.

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Acne VulgarisBiometryChloramphenicolClinical Trials as TopicColony Count, MicrobialConfidence IntervalsHumansModels, StatisticalRandomized Controlled Trials as TopicSample SizeComparative StudyJournal Article

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W Lehmacher, G Wassmer. 1999. Adaptive sample size calculations in group sequential trials.. https://doi.org/10.1111/j.0006-341x.1999.01286.x

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Acne Vulgaris↗