All psychiatrists in the greater Cincinnati area were sent a series of three questionnaires concerning patients from nonstructured discussion or T-groups. Twenty-four respondents reported having seen patients who had become psychotic or acutely disorganized in association with such group activity. They received a fourth questionnaire asking for details about the 19 patients involved and about the groups in which they participated. These 19 cases came from an estimated population of sensitivity-group participants of 2,900(0.66% casualties). Few (only five out of 1,750, or 0.28%) had been in structured "managerial grid" groups. Both positive and negative aspects of participation in sensitivity groups were elicited from the reported experience of these psychiatrists.
Ross WD, Kligfeld M, Whitman RW. Psychiatrists, Patients, and Sensitivity Groups. Arch Gen Psychiatry. 1971;25(2):178-180. doi:10.1001/archpsyc.1971.01750140082013