Several studies have indicated that large numbers of psychiatrically ill patients are admitted to medical and surgical wards of general hospitals.1-4Prevalence figures have ranged from 30% reported at the New York Hospital1to a remarkable 86% found by Zwerling and his associates on the wards of the Cincinnati General Hospital.3 The variations in reported prevalence undoubtedly reflect a number of factors, which may include: (1) differences in the characteristics of the patients served by the hospital; (2) the unreliability of the clinical psychiatric examination when used as a screening procedure; and (3) differences in criteria for the diagnosis of a psychiatric disturbance from one hospital to another. Physicians on a medical ward may be unaware of the fact that a large proportion of their patients are suffering from psychiatric disorders.3,4Only selective kinds of abnormal behavior are perceived as indicative of