A control group of 757 personnel and a test group of 1,875 neuropsychiatric patients were surveyed for symptoms and signs of allergy. In order to validate the material, the survey was made when an allergen (ragweed pollen) was a common environmental circumstance for both groups in the same geographical location. The survey, by history, among the control group revealed an incidence of major allergic symptoms of 21% and an incidence by physical signs of 13%. This group represented a cross section of the population for the area in which the study was made.Among the test group of patients, the majority of whom were psychotic, the incidence of symptoms by history was 5.7%, and the incidence of positive physical signs, 2.9%. The incidence of physical signs among schizophrenic patients was 2.9% and among manic-depressive psychotics, 1.4%. Among epileptics, it was 13% and among organic psychoses, 3.0%. The survey is considered valid since it was made under controlled conditions, the findings were objective, and the survey is open to repetition.Abstract Teaser