A Protocol for a Systematic Review of the Prevalence and Patterns of Substance Use and Related Disorders Among Children and Adolescents in South Pacific Nations

Substance use among children and adolescents is a significant public health concern, with early initiation linked to adverse mental health, developmental, and longer-term health outcomes. In the South Pacific, substance use is shaped by distinct socio-cultural, economic, geographic, and structural conditions, including traditional practices such as betel nut use and the challenges of delivering services across island communities. Although research has examined substance use among young people in the region, the literature remains heterogeneous and fragmented. No comprehensive synthesis has yet focused specifically on children and adolescents across South Pacific nations. This systematic review will synthesise evidence on the prevalence, patterns, and determinants of substance use and SUDs among children and adolescents in South Pacific countries. Searches will be conducted across MEDLINE, Embase, PsycINFO, CINAHL, and the Cochrane Library for publications from 2000 to 2026. Grey literature in region-focused repositories will also be searched. Observational studies reporting quantitative data on substance use among people aged 10–18 years will be included. Two reviewers will independently screen studies, extract data, and assess methodological quality using the Joanna Briggs Institute Critical Appraisal Checklist for Prevalence Studies. If sufficiently comparable data are available, meta-analysis will be conducted using random-effects models; otherwise, findings will be synthesised narratively.