RESUMEN
Objective:To analyze the data of vision acuity from primary and secondary school students in different regions in China in a screening program performed by Huaxia Eye Hospital, and to investigate the prevalence and incidence of myopia among them.Methods:A cross-sectional study was conducted.Cross-sectional and cohort analysis of the visual acuity and refraction data of primary and secondary school students in China from 2019 to 2021 from Huaxia Eye Hospital was carried out.Myopia was defined as one eye with the uncorrected visual acuity less than 5.0 and a spherical equivalent <-0.50 D in the screening.The frequency of screening, the number of people, the distribution of vision acuity, and the distribution of myopia among subjects were compared by sexes, grades and regions, and the prevalence and incidence of myopia was analyzed.Standard logarithmic visual acuity chart was used for visual examination and automatic computerized optometry was used for refractive examination.Screening process was consistent in the study.This study protocol was approved by the Ethics Committee of Xiamen Eye Center of Xiamen University (No.XMYKZX-KY-2019-011). The written informed consent was obtained from subjects or their guardians after explaining the examination procedure, methods and purpose prior to any medical examination.Results:A total of 4 027 schools in 51 cities of 19 provinces covering 4.556 million people were included in the vision study.The prevalence of myopia in screening was 64.85% in primary and secondary school population generally, 54.0% in primary school, 78.18% in junior high school and 87.05% in senior high school.There were statistical differences in the prevalence of screening myopia in different education stages ( χ2=100.7, P<0.001). The prevalence rate in females was higher than that in males ( χ2=5 557.5, P<0.001). The incidence of myopia within a year was 18.68% in primary and secondary schools, which was 16.57% in East China, 6.07% in Central China and North China, 15.11% in Southwest and Northwest China, 9.19% in South China, and there was a statistically significant differences among them ( χ2=1 200.9, P<0.001). Conclusions:The prevalence and incidence of myopia in primary and secondary school students are still high and vary with educational stages and regional factors.Scientific prevention and control of myopia should consider the two factors.