the powerful placebo challenged
The powerful effect of the placebo is not in doubt. It should be, however, according to Danish researchers Asbjørn Hróbjartsson and Peter C. Götzsche. Their meta-study of 114 studies involving placebos found "little evidence in general that placebos had powerful clinical effects...[and]...compared with no treatment, placebo had no significant effect on binary outcomes, regardless of whether these outcomes were subjective or objective. 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 ("Is the Placebo Powerless? An Analysis of Clinical Trials Comparing Placebo with No Treatment," The New England Journal of Medicine, May 24, 2001 (Vol. 344, No. 21)."
According to Dr. Hróbjartsson, professor of medical philosophy and research methodology at University of Copenhagen, "The high levels of placebo effect which have been repeatedly reported in many articles, in our mind are the result of flawed research methodology."* This claim flies in the face of more than fifty years of research. At the very least, we can expect to see more rigorously designed research projects trying to disprove Hróbjartsson and Götzsche.