Distinguishing Bipolar Depression, Major Depression, and Schizophrenia With the MMPI–2 Clinical and Content Scales

Clinical and content scales from the MMPI–2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) were used to examine the capacity of these scales to assist in the differential diagnosis of a sample of 212 psychiatric patients—137 with major depression; 43 with schizophrenia; and 32 with bipolar disorder, depressed state. Consistent with the previous literature, the clinical scales Depression (D), and Schizophrenia (Sc), and the content scales Depression (DEP), and Low Self-Esteem (LSE) best distinguished major depression from schizophrenia; the content scale DEP proved to be the most powerful predictor in distinguishing bipolar depression from schizophrenia. No clinical or content scale proved to be effective in distinguishing patients with bipolar depression from patients with major depression. In general, the content scales outperformed the clinical scales.