This is the program for the 2010 Joint Statistical Meetings in Vancouver, British Columbia.
|CE_31T||Wed, 8/4/2010, 1:00 PM - 2:45 PM||CC-8 (East)|
|Sample Size Re-estimation in Phase III Time-to-Event Clinical Trials with EastAdaptT Software — Continuing Education CTW|
|ASA , Cytel Software Corporation|
|Instructor(s): Cyrus R. Mehta, Cytel Inc.|
|The sample size of a clinical trial is usually determined by statistical power calculations. Often, however, there is uncertainty and debate as to what magnitude of alternative hypothesis treatment difference and between-patient variability it is appropriate to pre-specify. Hence there exist methods to facilitate re-estimation of the sample size in the light of interim efficacy results from the ongoing trial. This workshop will demonstrate the capabilities EastAdaptT, a module of the East® software system for designing and monitoring trials in which the sample size may be altered based on an unblinded interim analysis. Our emphasis will be on adaptive designs for censored survival data. Most sample size re-estimation methods require the use of a weighted statistic for the final analysis in order to preserve the type-1 error. This is non-intuitive and confusing to medical practitioners, involving the down-weighting of data contributed by one set of patients relative to the others. Eliminating the need for a weighted statistic, EastAdaptT utilizes the methods of Chen, DeMets and Lan (2004), and Gao, Ware and Mehta (2008). These methods will be highlighted in the workshop.|