MMPI measures as signs of predisposition to mental disorder among adoptees at high risk for schizophrenia

The DSM-III-R diagnoses of a group of adoptees were predicted by the MMPI (Minnesota Multiphasic Personality Inventory) schizophrenia-related scales in the Finnish Adoptive Family Study. The sample consisted of 60 high-risk (HR) adopted-away offspring of biologic mothers with a diagnosis of broad schizophrenia spectrum and 76 low-risk (LR) control adoptees. They were assessed with the MMPI before the onset of any psychiatric disorder at a mean age of 24 years. High scores on the Psychopathic Deviate scale predicted psychiatric disorder at 11-year follow-up. Furthermore, LR adoptees', but not HR adoptees', mental disorders could be predicted with the MMPI scales Psychopathic Deviate and Golden-Meehl Indicators. These scales measure schizophrenia-related personality traits, including asocial behavior, anhedonia, ambivalence, interpersonal aversiveness, and formal thought disturbances.