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Some optimal and non-optimal two-stage designs using an alpha-spending function.

H I Patel
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Abstract

While designing a group sequential clinical trial in the pharmaceutical industry setting, we often face a problem of determining the time for an interim analysis. For a two-stage trial we compute the sample sizes n and N per treatment group for the interim and final analyses, respectively, that minimize the average trial size for a specified overall power. We consider this optimization when we monitor the trial using a Lan-DeMets alpha-spending function. Two additional problems considered in this context are (i) finding the sample sizes that maximize the overall power for a specified average trial size, and (ii) finding the sample sizes that achieve specified powers at the interim and final analyses.

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BibTeXRIS

H I Patel. 1996-08-30. Some optimal and non-optimal two-stage designs using an alpha-spending function.. https://doi.org/10.1002/(sici)1097-0258(19960830)15%3A16%3C1739%3A%3Aaid-sim341%3E3.0.co%3B2-t

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