Slud E V
Mathematics Department, University of Maryland, College Park 20742.
Biometrics. 1994 Mar;50(1):25-38.
Several new methodological issues that arise within two-way factorial designs for survival experiments are discussed within the framework of asymptotic theory for the proportional hazards model with two binary treatment covariates. These issues include: the proper formulation of null hypotheses and alternatives, the choice among log-rank and adjusted or stratified log-rank statistics, the asymptotic correlation between test statistics for the separate main effects, the asymptotic power (under the various possible methods of analysis) of tests to detect main effects and interactions, the comparison of power to detect main effects within a 2 x 2 factorial design with power in a three-group trial where no patients are randomized simultaneously to both treatments, and the problems of analysis arising when accrual or exposure to one of the treatments is terminated early for ethical reasons.
在具有两个二元治疗协变量的比例风险模型的渐近理论框架内，讨论了双向析因生存实验中出现的几个新的方法学问题。这些问题包括：原假设和备择假设的恰当表述、对数秩检验与调整或分层对数秩统计量之间的选择、单独主效应检验统计量之间的渐近相关性、检测主效应和交互作用的检验（在各种可能的分析方法下）的渐近功效、在2×2析因设计中检测主效应的功效与在三组试验（其中没有患者同时被随机分配到两种治疗）中的功效比较，以及由于伦理原因提前终止一种治疗的入组或暴露时出现的分析问题。
