Prevalence of Refractive Errors among High School

Purpose: To determine the prevalence of refractive errors among high school students. Methods: In a cross-sectional study, we applied stratified cluster sampling on high school students of Aligoudarz, Western Iran. Examinations included visual acuity, non-cycloplegic refraction by autorefraction and fine tuning with retinoscopy. Myopia and hyperopia were defined as spherical equivalent of-0.5/+0.5 diopter (D) or worse, respectively; astigmatism was defined as cylindrical error>0.5 D and anisometropia as an interocular difference in spherical equivalent exceeding 1 D. Results: Of 451 selected students, 438 participated in the study (response rate, 97.0%). Data from 434 subjects with mean age of 16±1.3 (range, 14 to 21) years including 212 (48.8%) male subjects was analyzed. The prevalence of myopia, hyperopia and astigmatism was 29.3 % [95 % confidence interval (CI), 25-33.6%], 21.7 % (95%CI, 17.8-25.5%), and 20.7% (95%CI, 16.9-24.6%), respectively. The prevalence of myopia increased significantly with age [odds ratio (OR)=1.30, P=0.003] and was higher among boys (OR=3.10, P<0.001). The prevalence of hyperopia was significantly higher in girls (OR=0.49, P=0.003). The prevalence of astigmatism was 25.9 % in boys and 15.8 % in girls (OR=2.13, P=0.002). Th