Overall J E
Department of Psychiatry and Behavioral Science, University of Texas Medical School, Houston 77225.
Neuropsychopharmacology. 1990 Aug;3(4):233-5.
The p value associated with a test of significance is supposed to represent the probability of observed results given that the null hypothesis is actually true. In evaluating the efficacy of a new drug against placebo, regulatory considerations focus on superiority of the new drug over placebo. The disapproval consequence of placebo superiority is no different from the disapproval consequence of equivalence between drug and placebo. It is furthermore inconceivable that a drug company will submit a New Drug Application claiming superior efficacy for placebo. Thus, the only probability of concern is the probability that apparent superiority of drug over placebo is a chance finding, and that is the probability associated with a one-tailed test. Where multiple studies must be evaluated with regard to the regulatory decision, meta-analytic considerations further support the relevance of one-sided p values.
与显著性检验相关的p值应该表示在原假设实际为真的情况下观察到结果的概率。在评估一种新药相对于安慰剂的疗效时，监管方面的考虑集中在新药相对于安慰剂的优越性上。安慰剂优越性的不批准后果与药物和安慰剂等效性的不批准后果没有区别。此外，制药公司提交新药申请声称安慰剂具有更高疗效是不可想象的。因此，唯一值得关注的概率是药物相对于安慰剂的明显优越性是偶然发现的概率，而这就是与单尾检验相关的概率。在必须根据监管决策评估多项研究的情况下，荟萃分析的考虑进一步支持了单侧p值的相关性。
