The importance of the placebo effect is well known, and the use of the placebo in medicine dates back several centuries. A placebo was defined in 1811 as “any medicine adapted more to please than to benefit the patient” (http://triplehelixblog.com/2012/07/harnessing-the-placebo-the-human-side-of-medicine/). I take this 200-year-old definition to mean placebo can be powerful for subjective outcomes, such as pain measurements, and less important for objectively measured outcomes. Much of what we treat every day in medicine centers on improving subjective (patient-centered) outcomes. Meissner et al document the importance of the right comparator group in their systematic review on migraine prophylaxis therapy. As might be expected, the sham acupuncture and sham surgery control groups had a greater reduction of migraine frequency than the oral pharmacological placebo groups. Thus, in evaluating therapy for migraine prophylaxis, we learn from this review that like treatments should be compared, such as surgery treatment with sham surgery treatment and pill with sham pill. This important lesson extends far beyond migraine prophylaxis treatment.
Redberg RF. All Placebos Are Not Created Equally. JAMA Intern Med. 2013;173(21):1951. doi:10.1001/jamainternmed.2013.8544