Differentiating violent and nonviolent prison inmates by use of selected MMPI scales

Used multivariate procedures to determine whether prisoners who committed violent acts while in prison could be differentiated from those who did not. Ss were 141 adult male inmates in maximum security prisons. Multiple variable profile analysis that employed 22 MMPI scales and four demographic items significantly differentiated between violent and nonviolent inmates. Discriminant analysis that used all 26 variables yielded a significant root that accounted for 34.9% of the variance between violent and nonviolent inmates. The MMPI scales that contributed most to prediction of group membership were F, PA, PT, and Sc, all of which had discriminant load values above 0.40. Finally, a discriminant function prediction equation was derived to predict the criterion variable (violent or nonviolent behavior). Applying this equation without knowledge of the S's actual group membership correctly classified 72.9% of the violent and 80.6% of the nonviolent inmates.