Assessment of depression in mentally retarded adults.

Depression and psychopathology were assessed in 110 adult patients (ages 18-71 years) classified as borderline, mildly, moderately, or severely mentally retarded. Patients completed modified versions of the Beck Depression Inventory, the Zung Self-Rating Depression Scale, the MMPI depression scale, the Thematic Apperception Test, and the Psychopathology Instrument for Mentally Retarded Adults. Clinicians and ward personnel rated the patients on the Hamilton Rating Scale for Depression and an informant version of the Psychopathology Instrument for Mentally Retarded Adults. The measures correlated significantly with each other and were consistently related to the diagnosis of depression.