Effectiveness and implementation outcomes for peer-delivered mental health interventions in low- and middle-income countries: a mixed-methods systematic review.

PC-led interventions seem to show initial promise in terms of effectiveness, acceptability, feasibility, cost, fidelity, and sustainability. Future research should focus on standardizing measurements of implementation outcomes to facilitate cross-study analysis. Additional empirical attention should be paid to underrepresented implementation outcomes (e.g., cost, sustainability). Finally, researchers should adopt a participatory approach that elevates the perspectives of PCs throughout all stages of the implementation process.