Statistical Analyses
ocular abnormalities, myopia, cycloplegia failure
REGRESSION, MYOPIA, SENSITIVITY, SECONDARY
The main analysis was conducted in the full sample using the intention-to-treat principle except for the myopia incidence analysis, from which children with cycloplegia failure and ocular abnormalities were excluded. Missing values were imputed by multiple imputation.Continuous and categorical data were reported as means (SDs) and numbers (proportions), respectively. The normality in the distribution of continuous data was checked using the Kolmogorov-Smirnov normality test and histogram. All analyses took into account the cluster effects within schools. Baseline distributions of continuous (age, height, weight, and sleep time), binary (sex), and ordered categorical (outdoor time, screen time, and study or reading time) variables between the intervention and control groups were compared using linear, logistic, and ordinal logistic regression models, respectively. The statistical inference was determined on whether the lower limit of the 95% CI of the between-group mean difference in the primary outcome was no less than the predefined noninferiority margin. Linear regression models assessed the differences between the 2 study groups in mathematics scores, physical fitness scores, SER, and axial length at baseline and the end of 1 academic year and the changes in these variables after 1 academic year. Differences in the prevalence and incidence of myopia were compared by proportional Sensitivity analyses were performed using the per-protocol principle, which included only children who completed the intervention as originally assigned without any major protocol violation and children who completed the follow-up visit. Bonferroni correction was applied to multiple comparisons for secondary outcomes (physical fitness score and myopia incidence), and corrected 