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Use of restricted significance tests in clinical trials: beyond the one- versus two-tailed controversy
1Pfizer Central Research, Department of Clinical Research, Groton, CT 06340.
Abstract:
Whether to use "one-tailed" or "two-tailed" tests for clinical trials is examined in the more general context of restricted tests, developed by J. Neyman. This is complimented by a discussion of theoretical work of Savage and Bahadur. It is concluded that all tests of statistical significance have to be "restricted" in some sense and that failure to recognize the restrictions implied by "standard" methods of analysis can have a negative effect on the ability to detect treatment effects of new drugs in phase II and early phase III clinical trials.
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