Incremental validity of the MMPI-A content scales in a residential treatment facility.

The current study explores the incremental validity of the Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A) content scales. Participants were 335 adolescents (250 boys and 85 girls) between the ages of 13 and 18 who were receiving mental health services from a residential treatment facility. Regression analyses were conducted to identify the amount of additional variance accounted for by the content scales over the clinical scales in predicting scores on a clinician rating form of psychological symptomatology. Several of the MMPI-A content scales demonstrated significant incremental validity above the clinical scales in predicting clinician ratings of adolescents' behavior and personality characteristics. The clinical scales also demonstrated incremental validity in reference to the content scales, indicating then that the two sets of scales provide complementary information. Magnitude of the additional criterion variance predicted was modest.