An Experimental Study of the Placebo Effect in African Traditional Medicine

In an experimental study on the placebo effect in Malawi, an independent East African nation, 21 Malawian college students were tested individually in two 1-hour sessions on successive afternoons, using a one-group, two-condition before-after counterbalanced experimental design. Subjects were falsely told that a physiologically neutral substance they consumed would arouse the body, affecting oral temperature and pulse. Before-after measurements were taken during each day's session. On one of the days, the placebo resembled a traditional African herbal concoction, whereas on the other day, the placebo appeared to be a commercial Western-style medicine. The placebo effect was evaluated for each medication by comparing pre- and posttreatment scores. After the session, the subjects completed a questionnaire on their beliefs in the power of each style of medication. The placebo response was demonstrated in both medication conditions for oral temperature, but the strength of the placebo effect did not vary between medication styles. No significant relationship was found between the placebo effects and self-reported attitudes toward the two types of medication.