Centre for Clinical Epidemiology and Biostatistics, School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia.
BMC Psychiatry. 2020 May 14;20(1):239. doi: 10.1186/s12888-020-02641-w.
In medicine, it is common to observe improvement after intervention, at least partly because patients present for care in extremis and would have improved without intervention. Controlling for this counterfactual explanation for improvement is the principle reason to conduct a trial in which patients are randomised to treatment or a control group. Accordingly, it is not reasonable to infer that both interventions are effective when the groups show similar improvements in outcome.
在医学中,干预后观察到改善是很常见的,至少部分原因是患者在危急时刻就诊,如果不进行干预,他们的病情也会有所改善。控制这种改善的反事实解释是进行临床试验的主要原因,即在该试验中,患者被随机分配到治疗组或对照组。因此,当两组在结果上显示出相似的改善时,推断两种干预都有效是不合理的。