Systematic review of intervention functions, theoretical constructs and cultural adaptations of school-based smoking prevention interventions in low-income and middle-income countries.

Objective: To identify the approaches and strategies used for ensuring cultural appropriateness, intervention functions and theoretical constructs of the effective and ineffective school-based smoking prevention interventions that were implemented in low-income and middle-income countries (LMICs).

Data Sources: Included MEDLINE, EMBASE, Global Health, PsycINFO, Web of Science and grey literature which were searched through August 2022 with no date limitations.

Eligibility Criteria: We included randomised controlled trials (RCTs) with ≥6 months follow-up assessing the effect of school-based interventions on keeping pupils never-smokers in LMICs; published in English or Arabic.

Data Extraction And Synthesis: Intervention data were coded according to the Theoretical Domains Framework, intervention functions of Behaviour Change Wheel and cultural appropriateness features. Using narrative synthesis we identified which cultural-adaptation features, theoretical constructs and intervention functions were associated with effectiveness. Findings were mapped against the capability-motivation and opportunity model to formulate the conclusion. Risk of bias was assessed using the Cochrane risk of bias tool.

Results: We identified 11 RCTs (n=7712 never-smokers aged 11-15); of which five arms were effective and eight (four of the effective) arms had a low risk of bias in all criteria. Methodological heterogeneity in defining, measuring, assessing and presenting outcomes prohibited quantitative data synthesis. We identified nine components that characterised interventions that were effective in preventing pupils from smoking uptake. These include deep cultural adaptation; raising awareness of various smoking consequences; improving refusal skills of smoking offers and using never-smokers as role models and peer educators.

Conclusion: Interventions that had used deep cultural adaptation which incorporated cultural, environmental, psychological and social factors, were more likely to be effective. Effective interventions considered improving pupils' psychological capability to remain never-smokers and reducing their social and physical opportunities and reflective and automatic motivations to smoke. Future trials should use standardised measurements of smoking to allow meta-analysis in future reviews.