Myopia prevalence among students in nine-year and independent compulsory education schools: a retrospective cross-sectional study

This study aims to investigate the prevalence of myopia during compulsory education in the Nanshan district of Shenzhen and the relationship between myopic prevalence and different types of educational transitions.

Three different schools were purposively selected from the Nanshan district. One independent primary school and one independent secondary school together represented the discontinuous educational transition, and one nine-year school represented the continuous educational transition. The binomial logistic regression analysis was conducted to explore educational transitions associated with myopic prevalence.

Eight thousand ten students from two different educational transitions were involved in this retrospective cross-sectional study. The prevalence of myopia in the primary level (Grades 1-6) was 54.59%, while that in the secondary level (Grades 7-9) was 86.45%. The binomial logistic regression model revealed that the occurrence of myopia was significantly associated with females (OR = 1.60, 95% CI: 1.44-1.78; P < 0.001) and higher grade levels (P < 0.001). In exploratory analysis, students in the continuous educational transition showed lower odds of myopia than those in the discontinuous educational transition (OR = 0.85, 95% CI: 0.77-0.95; P = 0.003).

The prevalence of myopia was relatively high and surged from low-grade to high-grade levels among compulsory students in the Nanshan district. An association between the educational transition model and myopia prevalence was observed. However, this association was exploratory, because the educational transition exposure is fully confounded with school identity. Further longitudinal studies with multiple schools across diverse regions are warranted to clarify the specific mechanisms through which educational structure influences ocular health.