29 December 2010
The placebo effect has gotten a lot of positive press recently thanks to a new study, by Ted Kaptchuk et al (Harvard Medical School). He and his team took women suffering from irritable bowel syndrome and divided them into treatment and control groups. The control group received nothing while the treated group received twice-daily sugar pills.
Here's the twist, though: Kapthuck and his fellow researchers actually told the treated patients that what they were taking was nothing more than a sugar pill.
According to the study,
Before randomization and during the screening, the placebo pills were truthfully described [to the treated group] as inert or inactive pills, like sugar pills, without any medication in it. Additionally, patients were told that "placebo pills, something like sugar pills, have been shown in rigorous clinical testing to produce significant mind-body self-healing processes."
The end result was that the treated group had an improvement in their reported symptoms by the end of 21 days.
More coverage on the study can be found here and here. An interesting take on the study is NPR's, which reports that one study volunteer said that her symptoms disappeared after just a few days of taking the placebos and that, at the conclusion of the study, she bought placebos of her own. A more critical look is here.
My sense is that there may be more than one treatment being applied here -- not only was the treatment group told about the placebo, but they were actually told that placebos have been shown to "produce significant mind-body self-healing processes." So are these actually placebos?
What do you think? Do you find the study and its design persuasive? And what lessons do we draw from this?