Abstract:
:A general method is presented that allows the researcher to change statistical design elements such as the residual sample size during the course of an experiment, to include an interim analysis for early stopping when no formal rule for early stopping was foreseen, to increase or reduce the number of planned interim analyses, to change time points and the type I error spending function for the further design of interim analyses, or to change the test statistic, the outcome measure, etc. At the time of a pre-planned interim analysis for early stopping or at any time of an interim look without spending part of the type I error level the method offers the option to completely redesign the remaining part of the trial, without affecting the type I error level. The method is described in the usual Brownian motion model and extended to the general context of statistical decision functions. It is based on the conditional rejection probability of a decision variable.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Müller HH,Schäfer Hdoi
10.1002/sim.1852subject
Has Abstractpub_date
2004-08-30 00:00:00pages
2497-508issue
16eissn
0277-6715issn
1097-0258journal_volume
23pub_type
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