Impact of 'Double Reduction' policy on the trend of myopia in school-aged children in Eastern China.

Background: The high prevalence of myopia among school-aged children has become a significant global challenge. Implementing effective measures, including public policies, is essential to reducing its progression. In this study, we aimed to estimate the impact of the 'Double Reduction' policy, introduced in July 2021, on myopia progression among school-aged children in Eastern China. Methods: We conducted a longitudinal observational study from September 2019 to August 2022 in two cities in Eastern China. The study participants were schoolchildren receiving compulsory education from grades one to nine. We performed a regression discontinuity analysis to calculate the differences in spherical equivalent (SE) and axial length (AL) pre- and post-policy using both community-based and hospital-based cohort data. Results: Of the included 136 616 participants, 65 903 (48.24%) were girls. The mean age was 10.24 years (standard deviation (SD) = 2.94). Baseline SE averaged -1.47 D (standard error of the mean (SEM) = 0.01), and AL averaged 24.27 mm (SEM = 0.01). After one year of policy implementation, myopic progression was estimated to slow by 0.058 D (95% confidence interval (CI) = 0.043, 0.059) and -0.009 mm (95% CI = -0.05, 0.033) in the right eye within the hospital-based cohort. The community-based cohort showed a similar trend, with a change in SE of 0.115 D (95% CI = 0.017, 0.208) and AL of -0.163mm (95% CI = -0.375, 0.052). The policy had a greater effect on the participants with mild to moderate myopia compared to those with high myopia. Conclusions: The 'Double Reduction' policy slowed the myopia shift at the population level after one year of implementation. A public policy on education reduction might play a role in controlling myopia among schoolchildren, particularly in countries with high myopia prevalence.