The Prediction of Adjustment to Prison by Means of an MMPI-Based Classification System

Abstract

The predictive validity of an empirically derived, MMPI-based offender classification system was evaluated in a medium-security state facility. Incoming MMPI data were obtained for 495 male inmates, who were then assigned to one of ten categories or to an unclassified group using the computer program and clinical guidelines developed by Megargee and his colleagues. Behavioral measures of institutional adjustment (e.g., nights spent in correctional cell) during the first six months of incarceration served as the dependent variables, and a 2 × 7 (race by Megargee group) multivariate analysis was employed to investigate adjustment differences between the seven largest MMPI-based groups. Consistent with the results of previous studies, the classification system proved to be generalizable to a state population, with 92% of the inmates assigned to one of the ten categories. While between-groups differences in adjustment were observed, the most noteworthy finding was that these manifested themselves only among the white offenders, raising questions regarding the system's applicability to nonwhite populations.