Russek-Cohen E, Simon R M
Department of Animal Sciences, University of Maryland, College Park 20742, USA.
Stat Med. 1997 Feb 28;16(4):455-64. doi: 10.1002/(sici)1097-0258(19970228)16:4<455::aid-sim382>3.0.co;2-y.
We propose a two-stage procedure for investigating whether males and females respond differently to treatment. The size of the first stage is based on the assumption of homogeneity of treatment effects across genders. Using stage I, we test for a gender by treatment interaction. If non-significant, we compute an overall average treatment effect and terminate the study. If we find an apparent interaction at the end of the first stage, we consider each gender separately. Because we now need to estimate treatment effects separately for each gender, we may have a need to collect additional information in a second stage. We consider the performance of our procedure for a normally distributed endpoint as well as for a survival model.
我们提出了一个两阶段程序，用于研究男性和女性对治疗的反应是否不同。第一阶段的样本量基于治疗效果在不同性别间具有同质性的假设。在第一阶段，我们检验性别与治疗的交互作用。如果不显著，我们计算总体平均治疗效果并终止研究。如果在第一阶段结束时发现明显的交互作用，我们将分别考虑每个性别。由于我们现在需要分别估计每个性别的治疗效果，所以可能需要在第二阶段收集额外信息。我们考虑了该程序在正态分布终点以及生存模型方面的表现。
