Refractive error and visual impairment in school-age children in Gombak District, Malaysia

Purpose: To assess the prevalence of refractive error and visual impairment in school-age children in Gombak District, a suburban area near Kuala Lumpur city. Design: Population -based, cross-sectional survey. Participants: Four thousand six hundred thirty-four children 7 to 15 years of age living in 3004 households. Methods: Random selection of geographically defined clusters was used to identify the study sample. Children in 34 clusters were enumerated through a door-to-door survey and examined in 140 schools between March and July 2003. The examination included visual acuity measurements; ocular motility evaluation; retinoscopy and autorefraction under cycloplegia; and examination of the external eye, anterior segment, media, and fundus. Main Outcome Measures: Distance visual acuity and cycloplegic refraction. Results: The examined population was 70.3% Malay, 16.5% Chinese, 8.9% Indian, and 4.3% of other ethnicity. The prevalence of uncorrected (unaided), presenting, and best-corrected visual impairment (visual acuity :<= 20/40 in the better eye) was 17.1 %, 10.1 %, and 1.4%, respectively. More than half of those in need of corrective spectacles were without them. In eyes with reduced vision, refractive error was the cause in 87.0%, amblyopia in 2.0%, other causes in 0.6%, and unexplained causes in 10.4%, mainly suspected amblyopia. Myopia (spherical equivalent of at least -0.50 diopter [D] in either eye) measured with retinoscopy was present in 9.8% of children 7 years of age, increasing to 34.4% in 15-year-olds; and in 10.0% and 32.5%, respectively, with autorefraction. Myopia was associated with older age, female gender, higher parental education, and Chinese ethnicity. Hyperopia (>= 2.00 D) with retinoscopy varied from 3.8% in 7-year-olds, 5.0% with autorefraction, to less than 1 % by age 15, with either measurement method. Hyperopia was associated with younger age and other ethnicity. Astigmatism (>= 0.75 D) was present in 15.7% of children with retinoscopy and in 21.3% with autorefraction. Conclusions: Visual impairment in school-age children in urban Gombak District is overwhelmingly caused by myopia, with a particularly high prevalence among children of Chinese ethnicity. Eye health education and screening may help address the unmet need for refractive correction. Ophthalmology 2005;112:678-685 (c) 2005 by the American Academy of Ophthalmology.