Effectiveness and cost-effectiveness of videoconference and supported self-help mindfulness-based cognitive therapy (MBCT) for recurrent depression in the Spanish national health system: Protocol of the BECOME randomised controlled trial

Objective To evaluate the clinical and cost-effectiveness of two delivery formats of mindfulness-based cognitive therapy (MBCT)—(i) MBCT delivered through eight videoconference group sessions (group MBCT), and (ii) MBCT delivered through a self-help manual plus three low-intensity videoconference group sessions (supported MBCT self-help)—when added to treatment as usual (TAU), compared with TAU alone, in patients with recurrent depression. We will examine predictors, moderators, and psychological mechanisms of change. Methods Multicentre, superiority randomised controlled trial with assessments at baseline, post-intervention, and 6- and 12-month follow-ups. Patients (n=342) with recurrent depression, either in an acute episode or remission, will be recruited from Spanish NHS centres and randomly assigned to group MBCT, supported MBCT self-help, or TAU. Primary outcome: transition from remission to relapse/recurrence over 12 months (DSM-5-TR), analysed within a continuous-time multi-state model to evaluate longer-term trajectories. Secondary outcomes: transitions from acute depression to remission, depressive symptoms, well-being, quality of life, costs, and quality-adjusted life years. Process measures: mindfulness, affectivity, and self-compassion. The primary analysis will follow the intention-to-treat principle and continuous-time multi-state modelling to estimate transition-specific hazard ratios. Secondary outcomes and moderators will be analysed using regression-based approaches. Cost-effectiveness and cost-utility analyses will be conducted from healthcare system and societal perspectives, alongside mediation analyses. Participant experiences will be evaluated using qualitative methods. Conclusions This study will inform the integration of MBCT into routine mental healthcare in Spain for recurrent depression. Comparing the two delivery formats will provide evidence on effectiveness, cost-effectiveness, scalability, and efficient resource allocation.