Powerful placebo: the dark side of the randomised controlled trial
Powerful placebo: the dark side of the randomised controlled trial
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DOI：
10.1016/s0140-6736(97)10111-8
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发表时间：
1998-06-06
期刊：
影响因子：
168.9
通讯作者：
Kaptchuk, TJ
中科院分区：
文献类型：
--
作者：
Kaptchuk, TJ
哈佛医学院，总结和数学提出了一个观点，已经在一些精英生物医学研究中心自1946年以来发展。[12]比彻使用了一种原始荟萃分析方法，对15项临床试验中安慰剂治疗后令人满意的缓解患者的百分比进行了汇总。在1082例患者中，35· 2（SD 2· 2%）例患者出现治疗获益。这个被比彻称为“平均显著有效性”的数字并没有衡量改善的确切程度，尽管这是大多数人后来对他的论文的解释。比彻有力地论证了安慰剂缓解的不仅仅是心理问题，他引用的证据表明，“这些强大的安慰剂效应.可产生肉眼可见的物理变化”，其中“包括可能超过强效药理作用的终末器官的客观变化”。[11]比彻认为，无论一个人的智力如何，这种安慰剂效应都会起作用。比彻明确地假设了安慰剂效应的加性模型，“活性药物的安慰剂效应被它们的活性效应所掩盖.总的“药物”效应等于它的“活性”效应加上安慰剂效应”（原文引用）。[11]这一前提理所当然地认为，活性药物反应部分来自安慰剂效应，并且活性组中隐藏的安慰剂效应与模拟治疗的安慰剂效应相同。[13]安慰剂是一种单一而稳定的“力量”，其行为方式始终如一。新的安慰剂效应，一个由惰性物质产生的矛盾修饰法般的谜团，困扰着生物医学。直到今天，广泛的研究让科学家和哲学家得出结论，“目前使用的安慰剂概念不能以逻辑一致的方式定义，并导致矛盾”。14种解释性解释--期望、信念、经典条件反射、焦虑缓解、象征过程、医患关系、自我认知--争夺接受。安慰剂效应具有新催眠能量的属性。这是一个非常多变的概念：安慰剂反应者的反应或不反应似乎是随意的，15并且当与相同的药物相比时，对于相同的疾病，安慰剂效应可以在0%至100%之间变化。[16，17]神术安慰剂甚至可以更有效[18，19]，或者如比彻所指出的，完全逆转已知强效药物的结果。20
Harvard Medical School, summarised and mathematically presented a perspective that had been developing in a few elite biomedical research centres since 1946. 12 Beecher used a proto-meta-analytic method to aggregate the percentage of patients satisfactorily relieved by a placebo across 15 clinical trials. Of 1082 patients, 35· 2 (SD 2· 2%) experienced therapeutic benefits. This number, which Beecher called “average significant effectiveness” did not measure the exact magnitude of improvement, although that is how most people have subsequently interpreted his paper. Beecher argued forcefully that placebos alleviated beyond psychological problems by citing evidence that “these powerful placebo effects... can produce gross physical change”, which “include objective changes at the end organ which may exceed those attributable to potent pharmacological action”. 11 In an important revision of old orthodoxy, Beecher considered this placebo effect to operate regardless of the intelligence of a person. Beecher explicitly assumed an additive model of placebo effects,“The placebo effect of active drugs is masked by their active effects... The total ‘drug’effect is equal to its ‘active’effect plus its placebo effect”(quotes in the original). 11 This premise took for granted that the active drug response results partly from a placebo effect and that the placebo effect buried in the active arm is identical to the placebo effect of the dummy treatment. 13 The placebo was a single and stable “power” that behaved in a consistent manner. The new placebo effect, the oxymoron-like enigma of an effect produced by something that is inert came to haunt biomedicine. Still to this day, extensive examination leaves scientists and philosophers to conclude that “the placebo concept as presently used cannot be defined in a logically consistent way and leads to contradictions”. 14 Conflicting explanations—expectation, faith, classic conditioning, anxiety relief, symbolic processes, patient-doctor relationship, self-perceptions—vie for acceptance. The placebo effect has attributes of a neo-mesmeric energy. It is radically protean: placebo responders seem to react or not capriciously, 15 and for the same disease the placebo effect can vary between 0% to 100%, when compared with identical drugs. 16, 17 The theurgic placebo can even be more effective18, 19 or, as noted by Beecher, completely reverse the outcomes of known powerful pharmacological drugs. 20