标题： 因果推断与两种版本的处理 显示英文标题

标题： Causal Inference with Two Versions of Treatment

摘要： 因果效应通常被定义为处理组和对照组潜在结果的比较，但这种定义受到治疗或对照条件可能并非单一版本而是存在多个版本的可能性的威胁。 提出了一种简单且广泛适用的分析方法，以应对治疗或对照条件可能存在两种版本且具有两种不同治疗效果的可能性。 该分析在处理组与对照组的主要比较中不会失去任何功效，还能提供有关版本效应的额外信息，并在多次比较中控制了族wise误差率。 该方法是基于一项正在进行的研究而提出的，研究内容是重复性的头部创伤是否会导致高中生患早期痴呆的风险增加。 显示英文摘要

摘要： Causal effects are commonly defined as comparisons of the potential outcomes under treatment and control, but this definition is threatened by the possibility that the treatment or control condition is not well-defined, existing instead in more than one version. A simple, widely applicable analysis is proposed to address the possibility that the treatment or control condition exists in two versions with two different treatment effects. This analysis loses no power in the main comparison of treatment and control, provides additional information about version effects, and controls the family-wise error rate in several comparisons. The method is motivated and illustrated using an on-going study of the possibility that repeated head trauma in high school football causes an increase in risk of early on-set dementia.