Progression of myopia
Mean and standard deviations of the onset and final biometric measurements by refractive error type are given in Table 2 . The myopia prevalence was increased among refractive errors in observation periods (In the univariable analysis p = 0.029; in the multivariable analysis p= 0.017). The mean of the onset and the final SE were 0.19D (0.56), and 0.08D (0.80), respectively.
In the comparison of the onset biometric measurements between myopic and non-myopic children, AL was longer (p<0.001), ACD was deeper (p=0.001), LT was thinner (p=0.021) in myopic subjects. In myopic patients, the mean SE decreased by 0.69 D (0.41) in 3 years (p<0.001), while the mean AL increased by 0.49 mm (0.29) (p<0.001). In non-myopic patients, the mean SE increased by 0.04 D (0.30), and the mean AL 0.25 mm (0.33) in 3 years (p<0.001).
Factors associating the final SE of 41 children with myopia progression were evaluated by Cox regression analysis including the onset biometric parameters are given in Table 3 . SE was significantly correlated by age (HR:0.73, 95% CI: 0.57-0.92, β = -0.32, p = 0.009), AL (HR: 4.55, 95% CI:2.87-7.24, β = 1.52, p < 0.001), and Kmean (HR: 2.04, 95% CI:1.55-2.67, β = 0.71, p < 0.001). (Hazard ratio=HR)