Table 2. Age-standardized prevalence of refractive errors in the right eye (n = 33,355).

Myopia was defined as SE <-0.75 D and SE <-1.25 D for subjects aged 5 to 18 years. Complex sample analysis was performed with reference to weight, stratification variance, and cluster variance, following the statistical guidelines of the Korea Centers for Disease Control and Prevention. Age- and gender-standardized prevalence was provided based on post-stratified weight.

SE = spherical equivalent; D = diopters; CI = confidence interval; Cyl = cylindrical error.