Preplanned Studies: Cost-Effectiveness of Increasing Outdoor Activity in Preventing Myopia in Children and Adolescents — China

Introduction: Myopia has emerged as a major public health challenge affecting the visual health of children and adolescents in China. While evidence confirms the effectiveness of outdoor activity in preventing myopia, comprehensive economic analyses of its role in mitigating myopia-related diseases remain limited. Methods: This study employed a microsimulation model to evaluate the cost-effectiveness of increasing outdoor activity across different educational stages — primary, middle, and high school — for myopia prevention in China. The model simulated myopia progression among individuals aged 6 to 18 years, with the intervention defined as an additional 40 minutes of daily outdoor activity. Outcomes measured included changes in myopia prevalence, quality-adjusted life years (QALYs), and associated medical costs. Results: All intervention scenarios proved cost-effective, except for those targeting only the high school stage. Interventions focused on primary schools and combined primary–middle school stages not only improved health outcomes but also reduced medical costs. While the all-stages intervention yielded the greatest health benefits, its higher implementation costs make it more suitable for regions with greater resources. Conclusion: These findings highlight the critical importance of early intervention in myopia prevention. Policymakers should prioritize outdoor activity programs at the primary school level and develop tailored prevention strategies based on local resource availability. This study provides empirical evidence for developing scientifically sound, cost-effective myopia prevention strategies for children and adolescents, with relevant implications for other developing countries facing a high myopia burden.