Institute of Transcultural Health Sciences and Samueli Institute, European Office, European University Viadrina, PO Box 1786, 15203 Frankfurt (Oder), Germany.
Philos Trans R Soc Lond B Biol Sci. 2011 Jun 27;366(1572):1870-8. doi: 10.1098/rstb.2010.0401.
Control conditions were introduced through the trial of Mesmerism in Paris. Placebo controls became codified standard in 1946. Although seemingly unchallenged, there are various problems with this received view. The notion of a placebo is only defined from the negative. A positive notion proposed that placebo effects are effects owing to the meaning an intervention has for an individual. Thus, placebo effects are individualized, whereas standard research paradigms reveal only grossly averaged behaviour. Also, placebo effects are context sensitive, dependent on psychological factors such as expectancy, relief of stress and anxiety, and hence can generate strong and long-lasting treatment effects. These, however, are not predictable. Such a situation can lead to the efficacy paradox: sometimes, sham interventions can be more powerful than proved, evidence-based treatments. This situation has methodological consequences. Placebo-controlled randomized trials reveal only part of the answer, whether an intervention is effective. This is valuable information for regulators, but not necessarily also for patients and of limited value for providers. Hence, I have argued that we need to complement the hierarchical model of evidence by a circular one, in which various methods are employed on equal footing to answer different questions.
控制条件是通过巴黎梅斯梅尔主义试验引入的。安慰剂对照在 1946 年成为规范标准。尽管这一观点似乎没有受到挑战，但它存在各种问题。安慰剂的概念仅仅是从负面定义的。一个积极的概念是，安慰剂效应是由于干预对个体的意义而产生的效应。因此，安慰剂效应是个体化的，而标准的研究范式仅揭示了大致平均的行为。此外，安慰剂效应是情境敏感的，取决于心理因素，如期望、缓解压力和焦虑，因此可以产生强烈和持久的治疗效果。然而，这些是不可预测的。这种情况可能导致疗效悖论：有时，假干预可能比经过证实的、基于证据的治疗更有效。这种情况具有方法学上的后果。安慰剂对照的随机试验仅揭示了干预是否有效的部分答案。这对监管机构来说是有价值的信息，但对患者来说不一定，对提供者来说价值有限。因此，我认为我们需要用一个循环模型来补充证据的层次模型，在这个模型中，各种方法平等地用于回答不同的问题。
