Development of a short form of the adolescent version of the Defense Mechanisms Inventory

This article describes the construction of a short form of the adolescent version of the Defense Mechanisms Inventory (DMI; Gleser & Ihilevich, 1969; Ihilevich & Gleser, 1986). The DMI is a paper-and-pencil test for which subjects are asked to describe their reactions to 10 hypothetical dilemmas. The responses involve a forced choice method in which each of the alternative responses represent one of five defense clusters entitled Turning Against the Object, Principalization, Turning Against the Self, Reversal, and Projection. Two hundred ninety-five adolescent psychiatric patients (122 boys and 173 girls) ages 12-16 were administered the adolescent form of the DMI. Based on an analysis of each of the 10 dilemma stories, a 6-story short form was devised. Correlations between this short form and the long form of the DMI ranged from .90 to .95 on the five defense scales, with no significant effect of gender. Internal reliability estimates of the short form scales were also favorable. These results indicate that the short form of the adolescent DMI is an acceptable substitute for the lengthier inventory from which it was derived and is more utilizable in clinical and research settings.