Abstract:
:Conditional power based on summary statistic by comparing outcomes (such as the sample mean) directly between 2 groups is a convenient tool for decision making in randomized controlled trial studies. In this paper, we extend the traditional summary statistic-based conditional power with a general model-based assessment strategy, where the test statistic is based on a regression model. Asymptotic relationships between parameter estimates based on the observed interim data and final unobserved data are established, from which we develop an analytic model-based conditional power assessment for both Gaussian and non-Gaussian data. The model-based strategy is not only flexible in handling baseline covariates and more powerful in detecting the treatment effects compared with the conventional method but also more robust in controlling the overall type I error under certain missing data mechanisms. The performance of the proposed method is evaluated by extensive simulation studies and illustrated with an application to a clinical study.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Zou B,Cai J,Koch GG,Zhou H,Zou Fdoi
10.1002/sim.7454subject
Has Abstractpub_date
2017-12-30 00:00:00pages
4765-4776issue
30eissn
0277-6715issn
1097-0258journal_volume
36pub_type
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