Placebo Effect

what idiot called it a "randomized clinical trial controlled with placebo" and not "trick or treatment"

— this is dizzy stuff folks (@ACflurane) October 8, 2018</blockquote>

The placebo effect feels fundamentally important. We discovered that, in addition to the mechanistic response that medicine has, there is a kind of response based purely on belief and expectation. As best I can tell, we don’t understand how it works, or under what conditions. But we control for it when testing drugs.

Doesn’t this seem fundamental to understanding the human body and illness?

I would like to read an up-to-date, appropriately skeptical review of the current state of knowledge on the placebo effect.

“A 2001 Cochrane Collaboration meta-analysis of the placebo effect looked at trials in 40 different medical conditions, and concluded the only one where it had been shown to have a significant effect was for pain.”

Wikipedia

“For the trials with continuous outcomes, placebo had a beneficial effect, but the effect decreased with increasing sample size, indicating a possible bias related to the effects of small trials.”

The Cochrane meta-analysis

There is some indication (see SSC) that what we used to think of as the placebo effect is really just regression to the mean. See also a related discussion on LessWrong where the author points out that there is a whole package of relevant “control response”, of which the “placebo effect” (belief is curative) is only a small part.