In a duel between two placebos for treating self-reported arm pain,
the better placebo emerged victorious, Harvard researchers have found.
During the first two weeks of the comparative study, there was little
difference between sham acupuncture and a sugar pill, investigators
reported in BMJ Online First. However, differences began to emerge
during the following weeks showing that sham acupuncture produced
a more enhanced and surprisingly lasting placebo effect.
The study by Dr. Kaptchuk and colleagues showed that the patients
who reported improvements in symptoms were also those who
believed they were getting an active treatment. At two weeks, 75% of
the participants in the sham acupuncture group said they were
receiving an active treatment compared with only 48% of the sugar
pill group, indicating that believing may be key to feeling better.