Visual impairment and spectacle use in schoolchildren in rural and urban regions in Beijing

Purpose: To determine prevalence and associations of visual impairment and frequency of spectacle use among grade 1 and grade 4 students in Beijing. Methods: This school-based, cross-sectional study included 382 grade 1 children (age 6.3 +/- 0.5 years) and 299 grade 4 children (age 9.4 +/- 0.7 years) who underwent a comprehensive eye examination including visual acuity, noncycloplegic refractometry, and ocular biometry. Results: Presenting visual acuity (mean 0.04 +/- 0.17 logMAR) was associated with younger age (p = 0.002), hyperopic refractive error (p<0.001), and male sex (p = 0.03). Presenting visual impairment (presenting visual acuity <= 20/40 in the better eye) was found in 44 children (prevalence 6.64 +/- 1.0% [95% confidence interval (CI) 4.74, 8.54]). Mean best-corrected visual acuity (right eyes -0.02 +/- 0.04 logMAR) was associated with more hyperopic refractive error (p = 0.03) and rural region of habitation (p<0.001). The prevalence of best-corrected visual impairment (best-corrected visual acuity <= 20/40 in the better eye) was 2/652 (0.30 +/- 0.21% [95% CI 0.00, 0.72]). Undercorrection of refractive error was present in 53 children (7.99 +/- 1.05%) and was associated with older age (p = 0.003; B 0.53; OR 1.71 [95% CI 1.20, 2.42]), myopic refractive error (p = 0.001; B -0.72; OR 0.49 [95% CI 0.35, 0.68]), and longer axial length (p = 0.002; B 0.74; OR 2.10 [95% CI 1.32, 3.32]). Spectacle use was reported for 54 children (8.14 +/- 1.06%). Mean refractive error of the worse eyes of these children was -2.09 +/- 2.88 D (range -7.38 to + 7.25 D). Conclusions: Factors associated with presenting visual impairment were older age, myopic refractive error, and higher maternal education level. Despite a prevalence of myopia of 33% in young schoolchildren in Greater Beijing, prevalence of best-corrected visual impairment (0.30% +/- 0.21%), presenting visual impairment (6.64% +/- 1.0%), and undercorrection of refractive error (7.99% +/- 1.05%) were relatively low.