« Effet placebo », des convictions personnelles aux représentations collectives : relecture psychosociale d'un phénomène pharmacodynamique

After starting with a brief historical account of the placebo effect organized around the elaboration of clinical trials and around sham therapy as a method, we will offer a psychosocial point of view on the placebo phenomenon. The placebo effect is at the heart of medicine and particularly of therapeutic trials from theoretical research on a drug to its acceptance and its use in every-day clinical practice. The placebo effect intermingles biology, relationships and the context of therapeutic interactions. This type of phenomenon originates as much from biology as from human psychology. Our article puts more precisely into question the part that psychology has in the placebo phenomenon and suggests a chart to address it. This chart refers both to the pharmacodynamic effect given to drugs in a subjective way, and to the collective representations and social interactions depending on them. What can we say about the psychosociological dimensions of the placebo effect? How is it possible to organize the scope of these dimensions to base systematic studies on them in the field of clinical trials? We try to give elements of response to these questions by suggesting the study of the placebo effect as an original field of study by necessarily mobilizing both health sciences and the human and social sciences.