title: A note on sequential monitoring of select-the-winner design.
abstract: Consider a trial comparing two treatments or doses A and B with a control C. Based on a unblinded interim look, a winner W between A and B will be chosen, and future patients will be randomized to W and C and compared at the end of a study. The naïve test statistic Z under this setting follows an approximate normal distribution, as shown by Lan et al. (2006) and Shun et al. (2008). Results of these two articles apply only to the fixed sample size design. With simple modifications, this manuscript extends the previous works to the group sequential setting.
authors: a Model Based Drug Development , Janssen Research & Development LLC , Raritan , New Jersey , USA.
authors: K K Gordon
authors: KK
authors: Lan
authors: Fei
authors: F
authors: Chen
authors: Bob
authors: B
authors: Zhong
authors: Zhenming
authors: Z
authors: Shun
mesh_terms: D003627:Data Interpretation, Statistical; D016903:Drug Monitoring / Q000706:statistics & numerical data*; D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000379:methods / Q000706:statistics & numerical data*; D012107:Research Design / Q000706:statistics & numerical data*; D018401:Sample Size
keywords: Alpha spending; Brownian motion process; Sample size and power; Simulations