Comparing standard and technology-assisted Peer-delivered CBT for Perinatal Depression: A causal mediation study

Abstract

Background: The ENHANCE non-inferiority trial that took place in a deprived setting in Pakistan, demonstrated that a technology-assisted digital adaptation of the Thinking Healthy Programme (THPTAP), was no different than the face to face Thinking Healthy Programme in improving symptoms of perinatal depression. Examining potential mechanisms through which THP-TAP improved symptoms of perinatal depression, even in the absence of an intervention effect, is key as it can reveal underlying mechanisms of change, providing insight into features the intervention to target to improve outcomes. The present study examines the mechanisms through which THP-TAP improved symptoms of perinatal depressions (or not) compared to the face to face Thinking Healthy Programme. Methods: We applied a counterfactual-based approach to mediation, interventional effects, to decompose the total effect of THP-TAP intervention on symptoms of perinatal depression into the following pre-specified indirect effects: number of sessions attended; behavioural activation; perceived social support; problem-solving and cognitive-restructuring skills; and peer empathy. Mediators were assessed at 3 months postpartum, and depressive symptoms were measured at 6 months using the Patient Health Questionnaire-9