Gail M, Simon R
Biometrics. 1985 Jun;41(2):361-72.
Evaluation of evidence that treatment efficacy varies substantially among different subsets of patients is an important feature of the analysis of large clinical trials. Qualitative or crossover interactions are said to occur when one treatment is superior for some subsets of patients and the alternative treatment is superior for other subsets. A non-crossover interaction arises when there is variation in the magnitude, but not in the direction, of treatment effects among subsets. Some authors use the term quantitative interaction to mean non-crossover interaction. Non-crossover interactions are usually of less clinical importance than qualitative interactions, which often have major therapeutic significance. A likelihood ratio test is developed to test for qualitative interactions. Exact critical values are determined and tabulated.
评估治疗效果在不同患者亚组中存在显著差异的证据是大型临床试验分析的一个重要特征。当一种治疗方法对某些患者亚组更有效，而另一种治疗方法对其他亚组更有效时，就会发生定性或交叉相互作用。当亚组间治疗效果的大小存在差异但方向相同时，就会出现非交叉相互作用。一些作者使用“定量相互作用”一词来表示非交叉相互作用。非交叉相互作用通常在临床重要性上低于定性相互作用，而定性相互作用往往具有重大的治疗意义。本文开发了一种似然比检验来检测定性相互作用。确定并列出了精确的临界值。
