Power and sample size for randomized phase III survival trials under the Weibull model.
Two parametric tests are proposed for designing randomized two-arm phase III survival trials under the Weibull model. The properties of the two parametric tests are compared with the nonparametric log-rank test through simulation studies. Power and sample size formulas of the two parametric tests are derived. The sensitivity of sample size under misspecification of the Weibull shape parameter is also investigated. The study can be designed by planning the study duration and handling nonuniform entry and loss to follow-up under the Weibull model using either the proposed parametric tests or the well-known nonparametric log-rank test.
['Wu|Jianrong|J|']
D016009:Chi-Square Distribution D017326:Clinical Trials, Phase III as Topic D003198:Computer Simulation D018450:Disease Progression D018572:Disease-Free Survival D006801:Humans D053208:Kaplan-Meier Estimate D016013:Likelihood Functions D015233:Models, Statistical D010352:Patient Dropouts D018579:Patient Selection D016032:Randomized Controlled Trials as Topic D018401:Sample Size D013997:Time Factors D016896:Treatment Outcome
Sample size Log-rank test Proportional hazards model Randomized clinical trial Time-to-event Weibull distribution