Refractive Error and Visual Impairment in School Children in Rural Southern China Mingguang He, MD, MPH, 1,2 Wenyong Huang, MD, MPH, 1 Yingfeng Zheng, MD, 1 Li Huang, MD, 2,3 Leon B. Ellwein, PhD 4 Purpose: To assess the prevalence of refractive error and visual impairment in school children in a rural area of southern China. Design: Prospective cross-sectional survey. Participants: Two thousand four hundred children from junior high schools in Yangxi County. Methods: Random selection of classes from the 3 junior high school grade levels was used to identify the study sample. Children from 36 classes in 13 schools were examined in April 2005. The examination included visual acuity (VA) testing; ocular motility evaluation; cycloplegic autorefraction; and examination of the external eye, anterior segment, media, and fundus. Main Outcome Measures: Distance VA and cycloplegic refraction. Results: Among 2515 enumerated children, 2454 (97.6%) were examined. The study population consisted of the 2400 children between 13 and 17 years old. Prevalences of uncorrected, presenting, and best-corrected VA  20/40 in the better eye were 27.0%, 16.6%, and 0.46%, respectively. Sixty percent of those who could achieve acuity 20/32 in at least one eye with best correction were without the necessary spectacles. Refractive error was the cause in 97.1% of eyes with reduced vision; amblyopia, 0.81%; other causes, 0.67%; and unexplained causes, 1.4%. Myopia (spherical equivalent, -0.50 diopters [D] or more in either eye) affected 36.8% of 13-year-olds, increasing to 53.9% of 17-year-olds. Myopia was associated with higher grade level, female gender, schooling in the county urban center, and higher parental education. Hyperopia (+2.00 D or more) affected approximately 1.0% in all age groups. Astigmatism (0.75 D) was present in 25.3% of all children. Conclusions: Reduced vision because of uncorrected myopia is a public health problem among school-age children in rural China. Effective VA screening strategies are needed to eliminate this easily treated cause of visual impairment. Ophthalmology 2007;114:374 –382 © 2007 by the American Academy of Ophthalmology. It is well recognized that refractive error is a common cause of visual impairment in children. Using a standardized study protocol, 1 Refractive Error Study in Children (RESC) sur- veys have provided unprecedented comparative data on the prevalence of refractive error in school-age children at 8 sites worldwide. Surveys have been conducted in 2 areas of China: Shunyi District, 2 a semirural area outside of Beijing in northern China, and Guangzhou, 3 a large metropolis in southern China. Other RESC sites were in rural Jhapa District in eastern Nepal 4 ; La Florida, an urban area of Santiago, Chile 5 ; rural Mahabubnabar District near Hyder- abad in southern India 6 ; an urban area of New Delhi, India 7 ; a semiurban area of Durban, South Africa 8 ; and Gombak District in metropolitan Kuala Lumpur, Malaysia. 9 The study in Yangxi County was motivated by an inter- est in refractive error and visual impairment representative of the more remote rural areas of China, where a large proportion of children live. Although the prevalence of refractive error and need for corrective spectacles were largely unknown in rural China, it was believed that myopia would be less of a problem than in metropolitan areas, in line with a tendency for less academically rigorous classes and lower educational pressures in rural than in urban environments. 10 The emphasis in the Yangxi County survey was on examining children in the 13- to 15-year age range for comparison with the 2 previous RESC surveys in China. Because of the government’s 9-year compulsory educa- tion policy introduced in July 1986, school attendance rates are generally high among children in this age range; thus, it was thought that a sample representative of the Originally received: October 26, 2005. Accepted: August 15, 2006. Manuscript no. 2005-1027. 1 Key Laboratory of Ophthalmology and Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China. 2 Helen Keller International, New York, New York. 3 Guangming Eye Hospital, Yangjiang, China. 4 National Eye Institute, National Institutes of Health, Bethesda, Maryland. Supported by the World Health Organization, Geneva, Switzerland, under National Institutes of Health contract no. N01-EY-2103. The authors have no financial or other conflicts of interest concerning the study. Correspondence and reprint requests to Leon B. Ellwein, PhD, National Eye Institute, 31 Center Drive, MSC 2510, Bethesda, MD 20892-2510. E-mail: ellweinl@nei.nih.gov. 374 © 2007 by the American Academy of Ophthalmology ISSN 0161-6420/07/$–see front matter Published by Elsevier Inc. doi:10.1016/j.ophtha.2006.08.020