Differentiation of depression and anxiety groups using defense mechanisms.

We examined whether participants in depressed and anxious groups could be classified correctly using observer and self-report measures of defense mechanisms. A sample of 1182 university students completed the Personality Assessment Inventory and those scoring in the clinical range on either depression or anxiety indices were selected for participation. In total, 25 participants met criteria for the depressed group and 94 met criteria for the anxious group. Individual defense scores from the Defense-Q and the Defense Style Questionnaire were separately entered into 2 stepwise discriminant analyses. After cross-validation, the Defense-Q and Defense Style Questionnaire analyses classified participants with 75.0% and 71.3% accuracy, respectively. The results indicated that depression and anxiety groups can be significantly differentiated by defense use alone. Important differences in defensive functioning between these groups were confirmed and differences between observer and self-report measures of defenses mechanisms and current challenges in defense research were highlighted.