A Comparison of MMPI-2 Measures of Psychopathic Deviance in a Forensic Setting

We examined the convergent and discriminant validity of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) measures of psychopathy, including the Clinical Scale 4, Restructured Clinical Scale 4 (RC4), Content Scale Antisocial Practices (ASP), and Personality Psychopathology Five Scale Disconstraint (DISC). Comparisons of the empirical correlates of these scales were conducted with 2 samples of participants evaluated at a criminal court clinic. The 2 samples included 59 men and 19 women and 913 men and 327 women, respectively. Two types of criteria (clinician ratings and archival record review) were utilized in the analyses. Relative to Clinical Scale 4, RC4 had significantly greater convergent validity in predicting psychopathy as measured by the Psychopathy Checklist-Screening Version (S. D. Hart, D. N. Cox, & R. D. Hare, 1995) and behavioral criteria associated with this construct. RC4 also showed substantially improved discriminant validity when compared with its Clinical Scale counterpart. Among all the MMPI-2 scales studied, RC4 was the best measure of the social deviance traits of psychopathy.