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A clinical trial with an interim analysis
Author(s) -
Chi P. Y.,
Bristol D. R.,
Castellana J. V.
Publication year - 1986
Publication title -
statistics in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.996
H-Index - 183
eISSN - 1097-0258
pISSN - 0277-6715
DOI - 10.1002/sim.4780050411
Subject(s) - interim , interim analysis , sample size determination , statistics , clinical trial , sample (material) , mathematics , medicine , political science , physics , thermodynamics , law
We consider a fixed‐sample parallel‐group clinical trial with an interim analysis that tests H o : μ x = μ y against H 1 : μ x < μ y . If we do not reject at the interim analysis, then the probability of making a type I error by rejecting H o in favour of H 2 : μ x > μ y and the power at the final analysis are not appreciably affected by performing the interim analysis for certain relevant critical regions.