Prevalence of myopia and its influencing factors in primary school students in grades 4–6 in Ningbo

  Objective  To investigate the prevalence of myopia and related factors in primary school students of grade 4–6 in Ningbo, and provide scientific evidence for the myopia prevention and behavior intervention in primary school students.

  Methods  Through stratified cluster sampling, the questionnaire survey and myopia screening were conducted to describe the prevalence of myopia in the students selected. Unconditional logistic regression analysis was conducted to identify the related factors for myopia.

  Results  The myopia prevalence rate in 1088 primary school students was 61.5%. The results of multivariate analysis showed that the myopia prevalence rate was associated with residence (OR=0.547, 95% CI: 0.417–0.717), grade (OR=2.188, 95% CI: 1.556–1.251), daily homework times (OR=0.498, 95% CI: 0.327–0.759), weekly cram school time (OR=1.358, 95% CI: 1.019–1.809), distance between eye and book (OR=0.732, 95% CI: 0.549–0.976) and parents' myopia (OR=2.233, 95% CI: 1.706–2.922).

  Conclusion  Residence, grade, daily homework time, weekly cram school time, distance between eye and book, parents' myopia are the related factors for myopia in the primary school students of grade 4–6 in Ningbo. It is necessary to conduct targeted health education and behavior intervention to reduce the prevalence of myopia in primary school students.