Prediction of Adult Criminal Status from Juvenile Psychological Assessment

Abstract

A total of 121 juvenile offenders assigned to a regional assessment center in Medicine Hat, Alberta, Canada, for comprehensive psychological assessment between 1979 and 1984 were administered a test battery that included the WISC-R, the MMPI, and the Rorschach test. The offenders included 84 males and 37 females ages 12 to 15; among them were 48 Native Americans. In 1992, after a mean elapsed time of 9.9 years, all 121 were followed up and classified as either guilty ( n = 61) or not guilty ( n = 60) of a serious offense as an adult. Stepwise discriminant function analysis was used to find the best subset of variables with which to distinguish between the adults with a serious criminal record and those without. In order of importance, the four significant predictors selected from among 20 candidate variables were (a) the WISC-R comprehension subtest, (b) gender, (c) North American Native status, and (d) DQ+ from the Rorschach. A correct classification rate of 77.8% (as opposed to a base rate of 50.5%) was achieved, X2 (1) = 35.01, p<.001.