A systematic review of community-based counseling interventions for improving mental health and social well-being among vulnerable populations in Nigeria

Nigeria faces a substantial mental health burden, with an estimated 40-50 million individuals affected and a treatment gap exceeding 85%. Vulnerable populations, including internally displaced persons (IDPs) and conflict-affected women, children, and adolescents, experience compounded risks and severely limited access to care. Community-based counseling interventions delivered through task shifting have emerged as a promising strategy to bridge this gap. This systematic review aimed to systematically map the existing evidence on community-based counseling interventions designed to improve mental health and social well-being among vulnerable populations in Nigeria. A comprehensive search of PubMed, Scopus, Springer, Frontiers, ScienceDirect, AJOL, Springer, Cambridge Core, BMC, and grey literature sources was conducted for studies published between 2014 and 2026. Eligible studies included peer-reviewed articles and program evaluations of community-based counseling interventions targeting vulnerable Nigerian populations. A narrative synthesis was employed to map intervention types, delivery modalities, and outcomes. A total of 12 studies met the inclusion criteria. Vulnerable populations included IDPs, conflict-affected adolescents, women, and primary care patients. Interventions included group cognitive-behavioral therapy, didactic counseling, and integrated mental health and peacebuilding programs delivered by lay counselors and non-specialist health workers. Key findings demonstrated significant reductions in depression, anxiety, post-traumatic stress, and aggression. Community-based counseling interventions delivered through task shifting demonstrate considerable promise for improving mental health outcomes among Nigeria’s most vulnerable populations. However, the evidence base remains limited in geographic scope and methodological rigor. Future research should prioritize longitudinal, controlled studies across Nigeria’s diverse socio-cultural contexts to strengthen causal inference and inform sustainable scale-up.