Résumé
Background: the therapeutic use of psychedelics is revolutionizing current medical research in psychiatry. Scientific data are accumulating, particularly on the safety and efficacy of their use. However, the preparation of the participants (set) and the environmental conditions of taking a psychedelic (setting) have never been systematically reviewed. Methods: we conducted a systematic review of set and setting parameters in studies investigating the therapeutic use of psychedelics in subjects with a psychiatric diagnosis. Clinical trials published in the PubMed database up to 3 January 2022 were examined. The different parameters were classified into six domains: participant selection, pre-session and post-session interventions, monitor presence, environmental management, end-of-session procedure. Results: the studies included always consider set and setting in their protocol but our review shows that there are major differences when going into details of each parameter. Criteria concerning the selection of participants and the care taken to create a safe environment are present in all studies. Criteria relating to the presence of monitors were the least represented. Conclusions: common methodology emerges from the clinical trials, but there are differences in set and setting configuration that make comparability and reproducibility of results difficult. Harmonizing these aspects would increase the scientific validity of future studies and improve the understanding of the use of psychedelics in psychiatry.