Abstract:
:The treatment effect sizes that can be detected with sufficient power up to the different interim analyses constitute a clinically meaningful criterion for the selection of a group sequential test for a clinical trial. For any pre-specified sequence of effect sizes, it is possible to construct group sequential boundaries such that the trial has a pre-specified power to reject the null-hypothesis at or before the corresponding interim analysis under the respective treatment effect. The principle of constructing group sequential designs on the basis of detectable treatment effects is presented. The application in common situations such as two-armed trials with continuous or binary outcome or censored survival times is described. We also present an effective algorithm.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Schäfer H,Müller HHdoi
10.1002/sim.1751subject
Has Abstractpub_date
2004-05-15 00:00:00pages
1413-24issue
9eissn
0277-6715issn
1097-0258journal_volume
23pub_type
杂志文章abstract::We point out that the conventional methods for ties correction may be seriously biased when censoring times depend on covariates. A simple modification to the Efron correction method is suggested which works remarkably well in simulation studies. The method corresponds closely to breaking ties by random ordering. The ...
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journal_title:Statistics in medicine
pub_type: 临床试验,历史文章,杂志文章,随机对照试验
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journal_title:Statistics in medicine
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pub_type: 临床试验,杂志文章,随机对照试验
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pub_type: 杂志文章
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