Abstract:
:It has been widely recognized that interim analyses of accumulating data in a clinical trial can inflate type I error. Different methods, from group sequential boundaries to flexible alpha spending functions, have been developed to control the overall type I error at prespecified level. These methods mainly apply to testing the same endpoint in multiple interim analyses. In this article, we consider a group sequential design with preplanned endpoint switching after unblinded interim analyses. We extend the alpha spending function method to group sequential stopping boundaries when the parameters can be different between interim, or between interim and final analyses.
journal_name
J Biopharm Statjournal_title
Journal of biopharmaceutical statisticsauthors
Chen LM,Ibrahim JG,Chu Hdoi
10.1080/10543406.2014.901341subject
Has Abstractpub_date
2014-01-01 00:00:00pages
817-33issue
4eissn
1054-3406issn
1520-5711journal_volume
24pub_type
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