Just a few words of reassurance from a physician can have a substantial placebo effect on a patient’s pain symptoms, a US study shows.
In an experimental setting, healthy volunteers who had skin irritation induced by a histamine skin prick procedure reported one third less itchiness and irritation if they were given a few words of assurance by the ‘healthcare provider’ compared to a control group who received no reassurance.
In the study by psychology researchers at Stanford University, 76 participants were given a histamine skin prick on the forearm, in a dose known to be sufficient to elicit a minor local reaction.
Half of the participants were randomised to a group that was given assurance by the health provider at three minutes after the skin prick, while the other half formed a control group that received no reassurance.
With pain and irritation levels being recorded at three minute intervals, the researchers noted that levels diverged between the two groups after three minutes. Skin itchiness and irritation scores decreased markedly in participants in the assurance group compared to those in the control group. At nine minutes after the skin prick test, itchiness and irritation scores were around 20 in the assurance group compared to 30 in the control group. Both groups showed similar ongoing rates of decline in pain ratings but the assurance groups had levels that were significantly lower than those in the control group.
Publishing their findings in the Journal of General Internal Medicine, the study authors said their research was notable for showing the impact of using words alone rather than in conjunction with active intervention.