Survey of incidence of myopia in primary pupils and middle school students in Lanzhou city

Abstract

Objective To understand status of myopia in primary school pupils and middle school students in Lanzhou. Methods By using stratified clustered random sampling, 1 802 primary school pupils and middle school students from Chengguan district, Qilihe district, and Anning district of Lanzhou city, were enrolled in this study. Three schools were firstly chosen in each district, including one primary school, one junior middle school, and one senior middle school. Subsequently one class was randomly selected from each grade to investigate their ophthalmology status, including general visual acuity, intraocular pressure, computer optometry, and refractive parameters (measured by optical coherence biometry, IOLMaster, Zeiss). One-way ANOVA, Pearson correlation, and χ2 test was used to analysis these data. Results A total 1 802 students (3 604 eyes) were under checked. The total prevalence of myopia was 71.50% in primary pupils and middle school students of Lanzhou. The prevalence of myopia were 70.61% and 72.55% in males and females (χ2=10.43, P 0.05) were observed. Correlation analysis showed that refraction had various correlation intensities with different indexes, such as moderate correlation with height and body weight (r=-0.479, P 0.05). Conclusion The incidence of myopia was high in primary school pupils and middle school students of Lanzhou, with myopia occurred in females more often than in males. The prevalence of myopia increased with increasing grades, and refraction was correlated with visual acuity and axial length. Key words: Primary and middle school students; Myopia; Prevalence