Reexamination of the functional aggression scale’s validity among juvenile delinquents referred to Japanese family courts

Abstract

This study examined three validity types from the Functional Aggression Scale –factorial validity, cross validity, and criterion validity– using data from 382 Japanese juvenile delinquents referred to Japanese family courts. Confirmatory factor analysis showed that the Functional Aggression Scale consisted of four factors; however, free estimations were determined to be a better fit for the data than limiting the factor loading to 1. Multiple-group confirmatory factor analysis revealed the same degree of measurement invariance for the four juvenile delinquent characteristics studied (i.e., age, sex, residential area, and level of delinquency). The Wilcoxon rank-sum test for the factor scores indicated that the violent group’s mean scores for three separate factors (influence/coercion, punishment/retaliation, and identity) were significantly higher than those of the nonviolent group. Also, the violent group’s mean avoidance/defense factor score was not significantly higher than the nonviolent group.