Secondary outcomes of the guided self-help behavioral activation and physical activity for depression trial

Abstract

Background: This article presents secondary outcome variables from a randomized controlled trial evaluating the efficacy of two guided self-help interventions for the treatment of depression: behavioral activation (BA) and physical activity (PA). Both interventions resulted in significant reductions in depressive symptoms compared to the wait-list control group, however the mechanisms by which these interventions influenced depression were not presented. Purpose: The purpose of this paper was to compare changes in secondary outcome variables to gain insight into the mechanisms by which reactivation interventions reduce depressive symptoms. Results: Mixed-model analysis of variances (ANOVAs) revealed significant increases in life satisfaction (Main effect: F_{(3, 91.71)} = 4.63, p < 0.01) and self-efficacy (Main effect: F_{(3, 91.32)} = 4.05, p < 0.01) as well as significant decreases in negative affect (Main effect: F_{(2, 75.88)} = 5.24, p < 0.01) and loneliness (Main effect: F_{(2, 71.78)} = 7.49, p < 0.01) in both interventions at pre-, mid-, post-intervention and follow-up. The group x time interactions were not significant, suggesting that the PA and BA interventions had comparable effects over time. Conclusion: These findings provide insight into the potential mechanisms underlying the effectiveness of guided self-help PA and BA interventions on depressive symptoms.

Keywords: Behavioral activation; affect; depression; life satisfaction; loneliness; physical activity; self-efficacy.