Replicated 4×2 and two-stage-design, in the same pro­tocol [Two-Stage / GS Designs]

posted by Mauricio Sampaio  – Brazil, 2015-04-06 08:37  – Posting: # 14660
Views: 15,607

Are there any problem if, in the same protocol, replicated 4x2 and two-stage-design are considered?

For example, in first group were used 96 subjects on replicated (4x2) design with IC 95%. The result wasn't bioequivalent and the power was less than 80%. Therefore, a second group was added with 48 subjects, on replicated (4x2) design with the same IC 95%. In the end, first and second stage were combined and the result was bioequivalent.

I am to consider this strategy because I don't know how much variability of drug is that! But I would like to save money in the first moment risking a short number of subject and to have a opportunity to increase this number in the same study of bioequivalence.
Is it possible? Or I am crazy in front of the statistic and statisticians?:confused:

Edit: Category changed. [Helmut]

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