Study on the prevalence of myopia and its associated factors in China: a systemic review

Myopia is becoming more common, a significant public health issue everywhere, including in China. There needs to be a comprehensive analysis of the evidence about the extent of myopia in Chinese schoolchildren, despite earlier studies showing a growing frequency in China. Therefore, the frequency of myopia in Chinese schoolchildren is examined in this study with supporting data and a meta-analysis.

The 2022 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards were used for this research. From January 1, 2015, to December 31, 2022, five computerized bibliographic databases, including PUBMED, Scopus, Web of Science, ProQuest, and China Index Medicus, were reviewed and aimed at investigating myopia's prevalence in China. The studies' methodological quality was evaluated. Myopia is defined as a refractive error. Data were collected according to gender, age, and refraction method. The prevalence was calculated through a meta-analysis.

Data from 11 quality-assessed studies, with a total of 1,013,206 adolescents, were included. Hanting District children had an overall myopia prevalence of 45.47%, but Changyi children had a myopia prevalence of 82.37%. In general, 48.56, 47.30, and 31.62% of elementary, middle, and higher school pupils had mild myopia, compared to 1.12, 8.89, and 20.12% who had high myopia. Children aged 7-9 years old experienced the largest overall increase in the prevalence of myopia. For girls and boys, the prevalence of higher myopia was 7.59% and 6.43% (p<0.001). Yet, the spherical equivalent (SE) dropped as students' ages and grades rose. Myopia prevalence rises as students age and grade.

The recent findings revealed that myopia predominated among schoolchildren in Weifang. It steadily grew through age, in addition to it being more common in Changyi neighborhoods. Females had a greater frequency of myopia than males.