Epidemiology characteristics for non-myopic Chinese children aged 6 to 12 years in Jiangsu Province

Background: We aimed to present epidemiology characteristics including SE value, age, BMI, sex for non-myopic Chinese children after indicating the prevalence of myopia among children aged six to twelve . Based on these we were trying to develop alert values for predicting the future onset of myopia. Methods: All students took part in the ophthalmic examination filled in a questionnaire to provide basic demographic information. We used an autorefractor applying with cycloplegia to obtain spherical equivalent value, and part of their parents filled in a questionnaire of factors related to myopic among children. Results: We finally had 3900 non-myopic observations from 6362 students, and the prevalence of myopia is 38.0% for boys and 39.5% for girls respectively. The average values for SE were 0.5±0.7 for boys and 0.6±0.8 for girls respectively. The mean SE decreased with age in children, and the value of height and BMI took on a stable trend. Alert values for myopia could be set as follows, for children aged six years of age, 0.4-0.6 D for boys and 0.8-1.0 D for girls respectively. For children aged seven years of age, 0.4-0.6 D for boys and 0.3-0.5 D for girls respectively, for children aged eight years, 0.2-0.4 D for boys and 0.3-0.5D for girls, for children aged nine years, 0.2-0.4 D for boys and 0.3-0.4D for girls, 0.1-0.3 D for boys aged ten and 0.3D for girls aged ten years, 0.10-0.3 D for boys aged eleven and -0.3-0.3 D for girls aged eleven years, and for children aged twelve ,-0.1-0.1 D for boys and -0.3-0.1 D for girls aged twelve years. Father’s myopia ( OR:1.22,95%CI:1.01-1.48 ), near work on weekends (OR:2.56,95%CI:1.17-5.61) and outdoor activities (OR:0.68,95%CI:0.54-0.86) had an impact to non-myopic students with myopic alerting. Conclusion: Our study presented an epidemiology description for non-myopic students in Jiangsu Province, and we proposed a series of alert values to provide early warning reference for Chinese children aged six to twelve years. We draw a nomograph to predict the probability of myopia onset and found that family, near work and outdoor activities, had an impact on non-myopic students with myopic alerting.