Prevalence and risk factors of myopia among children and adolescents in Hangzhou

To analyze the prevalence and influencing factors of myopia among children and adolescents in Hangzhou city, and provide ideas for the formulation of myopia prevention and control measures. A cross-sectional school-based study using stratified cluster random sampling method was used to select 31,880 students from 113 schools in Hangzhou city. Myopia screening and questionnaires on the influencing factors of poor visual acuity were carried out. Univariate and multivariate logistic regression were used to screen possible risk factors of myopia. The overall prevalence of myopia was found to be 55.3% (17,630/31,880), with the myopia rates observed among students in kindergarten, primary school, junior high school, and senior high school, at 5.8%, 34.9%, 74.2%, and 85.0%, respectively. As the academic year progresses, there has been an observable increase in the prevalence of myopia (χ² = 8676.748, P<0.001), low myopia (χ² = 5444.040, P<0.001) and high myopia (χ² = 2171.073, P<0.001) among students, with the difference between the three groups being statistically significant. The myopia prevalence in girls is higher than that in boys (χ² = 119.917, P<0.001); the prevalence of myopia in urban students is higher than that in suburban students (χ² = 4.603, P = 0.032). The time spent on homework after school, the correctness of reading and writing postures, the duration of exposure to electronic screens, and the use of lighting in an appropriate manner all have an impact on the development of myopia (all P<0.05). The overall prevalence of myopia and high myopia in schools in eastern China, is notably high. The prevalence of myopia and high myopia increases with grade or age. Myopia is associated with increased age, parental myopia, extended periods of homework after school, poor reading and writing posture, prolonged exposure to electronic screens and inappropriate lighting. In light of the findings of the present survey, it is recommended that a comprehensive prevention and control intervention model for myopia in children and adolescents based on society-hospital-school-family-individual students with a view to preventing and controlling myopia.