To determine the prevalence of amblyopia and its association with refraction in Chinese preschool children.Methods
The Yuhuatai Pediatric Eye Disease Study, a cross-sectional, population-based study, was conducted in children aged 36–48 months in Yuhuatai District, Nanjing, China, in 2015. Visual acuity was measured in 1695 eligible children.Results
Of the 1695 subjects, manifested amblyopia was detected in 25 children (1.47%, 95% CI 0.90% to 2.05%), including 11 and 14 with bilateral and unilateral amblyopia, respectively. Amblyopia prevalence did not differ by gender (p=0.77). Significant refractive errors were found in 22 (88.0%) of children with amblyopia, and strabismus was found in 6 (24.0%) children with amblyopia. In multivariate analysis, amblyopia was significantly associated with hyperopia (≥+2.00 dioptres (D); OR 8.81, 95% CI 3.27 to 23.69, p<0.0001), astigmatism (≥2.00 D; OR 17.90, 95% CI 6.78 to 47.21, p<0.0001) and anisometropia (≥2.00 D; OR 5.87, 95% CI 1.52 to 22.77, p<0.05).Conclusions
The prevalence of amblyopia in children 36–48 months old in Eastern China was 1.47%. The refractive error is a major risk factor for amblyopia.