Original ArticleRefractive Error and Visual Impairment in School Children in Rural Southern China
Section snippets
Sample Selection
Stratified cluster sampling was used to select the study sample. The sampling frame was constructed through enumeration of grade-specific classes within the 17 county schools. Each class, with anywhere between 50 and 80 students, represented a sampling frame cluster. Based on Bureau of Education data, 8382 students were enrolled in 132 classes at the seventh grade level, 7400 were in 112 classes at the eighth grade level, and 5628 were in 88 classes at the ninth grade level. Stratification of
Study Population
The enumeration and examination of children took place during April 2005. A total of 2454 children were examined, representing 97.6% of the 2515 enumerated. Distributions across age, gender, grade level, school location, and residence are shown in Table 1. Because of small numbers, meaningful estimates of myopia rates for 12- and 18-year-olds (54 examined subjects) were not possible, and they were excluded from the study population.
Visual Acuity
Visual acuity findings are presented in Table 2. Uncorrected
Discussion
This study provides estimates of the prevalence of refractive error and visual impairment in junior high school children in rural Yangxi County. Findings indicate that myopia prevalence is higher among children attending schools in the urban center of the county than among those in schools in the rural countryside. These urban–rural comparisons were not possible in the previous Shunyi District survey because it excluded the urban center of the district, expecting that obtaining access for
References (29)
- et al.
Refractive Error Study in Children: sampling and measurement methods for a multi-country survey
Am J Ophthalmol
(2000) - et al.
Refractive Error Study in Children: results from Shunyi District, China
Am J Ophthalmol
(2000) - et al.
Refractive Error Study in Children: results from Mechi Zone, Nepal
Am J Ophthalmol
(2000) - et al.
Refractive Error Study in Children: results from La Florida, Chile
Am J Ophthalmol
(2000) - et al.
Refractive error and visual impairment in school-age children in Gombak District, Malaysia
Ophthalmology
(2005) - et al.
How genetic is school myopia?
Prog Retin Eye Res
(2005) - et al.
The progression of refractive error in school-age children: Shunyi District, China
Am J Ophthalmol
(2002) - et al.
Refractive error and visual impairment in urban children in southern China
Invest Ophthalmol Vis Sci
(2004) - et al.
Refractive error in children in a rural population in India
Invest Ophthalmol Vis Sci
(2002) - et al.
Refractive error in children in an urban population in New Delhi
Invest Ophthalmol Vis Sci
(2002)
Refractive error and visual impairment in African children in South Africa
Invest Ophthalmol Vis Sci
Nearwork in early-onset myopia
Invest Ophthalmol Vis Sci
Cited by (0)
Manuscript no. 2005-1027.
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.