Mechanisms of change in cognitive therapy of depression

This study examined the mechanisms which contribute to the efficacy of Beck's cognitive therapy for depression and identified some of the depressive responses influenced by this treatment. Cognitive therapy was administered in a small group format semiweekly for 6 weeks to 37 community volunteers with moderate to severe major depressive disorder. Cognitive therapy was divided into three components: self-monitoring (SM), logical analysis (LA), and hypothesis testing (HT). Generally, exposure to LA, to HT, or to all components was associated with self-reports of fewer depressive symptoms and dysfunctional thoughts, more pleasant events, and better interpersonal relationship than occurred before treatment. There were no significant differences between LA and HT on any variable. Exposure to all components or to more treatment was associated with significantly fewer depressive symptoms (BDI) and dysfunctional thoughts (ATQ-F) than was exposure to only LA or to only HT. However, according to the MMPI-D, ATQ-B, PES and IES, exposure to the combination equalled exposure to only LA or HT. Pretreatment levels of negative automatic thoughts did not predict response to cognitive therapy, while pretreatment BDI scores accounted for 16% of the variance in posttreatment BDI scores.