INFLUENCE OF THE BEHAVIOR PATTERN ON THE NOCEBO RESPONSE OF HEALTHY-VOLUNTEERS

The occurrence of a nocebo effect after placebo administration to heal thy volunteers in a Phase I trial was analysed according to their type of personality (Bortner Rating Scale). More subjects with a behaviour pattern A (competitive and aggressive) (50%) described subjective sid e effects of the placebo than type B subjects (17%, P = 0.03). The vol unteers who had nocebo effect had a higher Bortner score (BS) than did placebo non-responsive subjects (P = 0.05). The BS was 205 for parame dical staff, 189 for medical and dentistry students, 173 for non-scien ce students and 161 for science students (P < 0.04). The nocebo respon se was not statistically correlated with professional status. These re sults suggest that volunteer's type of personality might influence the reporting of subjective symptoms after placebo, and therefore impair the evaluation of new drugs in Phase I clinical trials.