[Population-based survey of refractive error in school-aged children in Liwan District, Guangzhou]

To estimate the prevalence of refractive error in school-aged children in urban setting of Southern China.

In this population-based cross-sectional study, children aged 5 to 15 years old were randomly selected by clustering sampling and door-to-door survey, and were examined in 71 schools and 19 community stations from October 2002 to January 2003. The examination included visual acuity measurement, ocular motility evaluation, retinoscopy, autorefraction under cycloplegia and examination of the external eye, anterior segment, media, and fundus.

Of 5053 children living in 4814 households enumerated, 4364 (86.4%) were examined. The prevalence of myopia (spherical equivalent, SE < -0.50 D) was 35.1% (95% CI: 33.2%-36.9%) with retinoscopy, this rate increased from 3. 3% in 5-year-old to 73.1% in 15-year-old. Females had a significantly higher risk of myopia (adjusted odds ratio: 1.29, 95% CI: 1.11-1.51). The prevalence of hyperopia (SE > or = + 2.00 D) was 5.8% (95% CI: 5.3%-6.3%) and decreased from 16.7% in 5-year-old to less than 1% in 15-year-old. Astigmatism (cylinder > or = 0.75 D) was presented in 33.6% of children examined with retinoscopy and in 42.7% with autorefraction.

The prevalence of myopia is high in Chinese school-age children living in urban Guangzhou, representing an important public health problem. The coverage and quality of refractive correction in the children need to be improved.