Urban-rural differences in refractive status and visual behaviors among preschool children aged 3-6 years in Shunyi district, Beijing: a multidimensional analysis

To investigate urban-rural differences in refractive status among children aged 3-6 years in Shunyi District, Beijing, and their associations with daily visual behaviors, as well as to ascertain the relative contributions of familial risk and environmental factors in this population.

A total of 1,142 children (527 in urban areas and 615 in townships) from 11 kindergartens in Shunyi District were selected through stratified cluster random sampling. After fully paralyzing the ciliary muscle with 1% cyclopentolate, computerized refraction was performed to calculate the spherical equivalent (SE). Standardized questionnaires were used to obtain eye-use duration, eye-use distance, outdoor activity time and parental myopia history. Multifactor logistic regression and structural equation modeling (SEM) were used to analyze myopia risk factors and their path relationships.

The overall myopia prevalence was 3.85% (3.23% in urban and 4.39% in rural areas), with no significant urban-rural difference (χ ² = 1.308, p = 0.253). No significant associations of sex, age, or urban-rural status on myopia prevalence, visual behaviors, or outdoor time were observed. Multivariable logistic regression indicated that parental myopia was independently associated with myopia in preschool children (OR = 4.892, 95% CI: 2.675-8.954, p < 0.001). SEM showed good fit (RMSEA = 0.024, CFI = 0.978) and revealed a significant positive direct association of parental myopia with childhood myopia (standardized path coefficient β = 0.32, p < 0.05), which was numerically stronger in urban children. The direct associations of near work load (β = 0.08) and outdoor activity (β = -0.07) were not statistically significant (p > 0.05).

Myopia prevalence and visual behavior patterns in preschool children in Shunyi District are homogenized between urban and rural areas. In this age group, parental myopia is the only statistically significant independent predictor of childhood myopia (OR = 4.87). This study systematically examined the prominent role of familial risk in a preschool population from the same urban-rural fringe area, and proposed the hypothesis that "familial risk becomes more prominent following convergence in measured visual behaviors." Based on these findings, we propose a tiered strategy for myopia prevention and control.