title: Point and interval estimation of primary and secondary parameters in a two-stage adaptive clinical trial.
abstract: Investigated in this paper is the point estimation and confidence intervals of the treatment efficacy parameter and related secondary parameters in a two-stage adaptive trial. Based on the minimal sufficient statistics, several alternative estimators to the sample averages are proposed to reduce the bias and to improve the precision of estimation. Confidence intervals are constructed using Woodroofe's pivot method. Numerical studies are conducted to evaluate the bias and mean squared error of the estimators and the coverage probability of the confidence intervals.
authors.affiliation: Department of Health and Human Services, Biometry and Mathematical Statistics Branch, National Institute of Child Health and Human Development, Rockville, Maryland 20852, USA. Liua@mail.nih.gov
authors.forename: Aiyi
authors.initials: A
authors.lastname: Liu
authors.forename: Chengqing
authors.initials: C
authors.lastname: Wu
authors.forename: Kai F
authors.initials: KF
authors.lastname: Yu
mesh_terms: D002986:Clinical Trials as Topic / Q000379:methods / Q000706:statistics & numerical data*; D016001:Confidence Intervals; D023381:Endpoint Determination; D006801:Humans; D015233:Models, Statistical; D018401:Sample Size