The Placebo Placebo Effect

In the June 1 issue of Newsweek, Sharon Begley discusses how placebos really work, in the process revealing that

As far as the body is concerned, a placebo is nothing—a sugar pill, a sham treatment, an inert compound. But try telling that to the brain, as scientists led by Daniel Cherkin of Group Health Center for Health Studies in Seattle recently saw. They assigned 638 adults with chronic lower-back pain to receive either standard acupuncture therapy, customized acupuncture (tailored to the individual, such as by using nonstandard acupuncture points), sham acupuncture (toothpicks in acupuncture-needle guide tubes that mimic the feel of real acupuncture) or standard back-pain care, such as anti-inflammatory drugs and massage. As the scientists reported this month in Archives of Internal Medicine, pain diminished significantly for 60 percent of the people in all three acupuncture groups—but for just 39 percent of patients receiving usual care. On average, both fake and real acupuncture reduced pain more than twice as much as standard care. Weirdly, this is being spun as "acupuncture is better than standard medical care for back pain!" I say "weirdly" because the key finding is that sham acupuncture delivered as much benefit as real acupuncture. And the most parsimonious explanation for that finding is inescapable: it is possible to think yourself out of pain.

The rest is here.