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Updated: Aug 17, 2026
A Two-interval Forced-choice Task for Multisensory Comparisons
Published on: November 9, 2018
p-value and power computations in multiple look trials
Abstract:
This paper presents at an instructive level detailed design, decision and computational aspects of p-values and power for clinical trials in which interim looks at accumulating data are planned. Background theory and an application are presented. In addition, a definition of the term p-value, appropriate for a trial in which interim looks are planned is proposed. The definition is intuitively consistent with that for a fixed sample size trial. That is, the p-value reflects the strength of the data against the null hypothesis. For trials incorporating group sequential methods, the p-value at a particular look reflects the conditional nature of the data collected through that look on the data collected through earlier looks.
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