Mediation analyses of Internet-facilitated cognitive behavioral intervention for maternal depression

This study evaluated the putative mediating mechanisms of an Internet-facilitated cognitive-behavioral therapy (CBT) intervention for depression tailored to economically disadvantaged mothers of preschool-age children. The CBT mediators were tested across two previously published randomized controlled trials which included the same measures of behavioral activation, negative thinking, and savoring of positive events. Trial 1 included 70 mothers with elevated depressive symptoms who were randomized to either the eight-session, Internet-facilitated intervention (Mom-Net) or to treatment as usual. Trial 2 included 266 mothers with elevated depressive symptoms who were randomized to either Mom-Net or to a motivational interviewing and referral to services condition. Simple mediation models tested each putative mediator independently followed by tests of multiple mediation that simultaneously included all three mediators in the model to assess the salient contributions of each mediator. The pattern of results for the mediating effects were systematically replicated across the two trials and suggest that behavioral activation and negative thinking are salient mediators of the Mom-Net intervention; significant mediating effects for savoring were obtained only in the simple mediation models and were not obtained in the multiple mediation models.