title: Population-based survey of refractive error among school-aged children in rural northern China: the Heilongjiang eye study.
abstract: BACKGROUND
  The prevalence of refractive error in the north of China is unknown. The study aimed to estimate the prevalence and associated factors of refractive error in school-aged children in a rural area of northern China.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  The cluster random sampling method was used to select the sample.
  
  
  METHODS
  A total of 1700 subjects of 5 to 18 years of age were examined. All participants underwent ophthalmic evaluation. Refraction was performed under cycloplegia. Association of refractive errors with age, sex, and education was analysed.
  
  
  METHODS
  The main outcome measure was prevalence rates of refractive error among school-aged children.
  
  
  RESULTS
  Of the 1700 responders, 1675 were eligible. The prevalence of uncorrected, presenting, and best-corrected visual acuity of 20/40 or worse in the better eye was 6.3%, 3.0% and 1.2%, respectively. The prevalence of myopia was 5.0% (84/1675, 95% CI, 4.8%-5.4%) and of hyperopia was 1.6% (27/1675, 95% CI, 1.0%-2.2%). Astigmatism was evident in 2.0% of the subjects. Myopia increased with increasing age, whereas hyperopia and astigmatism were associated with younger age. Myopia, hyperopia and astigmatism were more common in females. We also found that prevalence of refractive error were associated with education. Myopia and astigmatism were more common in those with higher degrees of education.
  
  
  CONCLUSIONS
  This report has provided details of the refractive status in a rural school-aged population. Although the prevalence of refractive errors is lower in the population, the unmet need for spectacle correction remains a significant challenge for refractive eye-care services.
authors: Department of Ophthalmology, the First Affiliated Hospital of Harbin Medical University, Harbin.
authors: Zhijian
authors: Z
authors: Li
authors: Keke
authors: K
authors: Xu
authors: Shubin
authors: S
authors: Wu
authors: Jia
authors: J
authors: Lv
authors: Di
authors: D
authors: Jin
authors: Zhen
authors: Z
authors: Song
authors: Zhongliang
authors: Z
authors: Wang
authors: Ping
authors: P
authors: Liu
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D006302:Health Services Research; D006306:Health Surveys; D006801:Humans; D008297:Male; D015995:Prevalence; D012030:Refractive Errors / Q000175:diagnosis / Q000453:epidemiology*; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data*; D017678:Sex Distribution; D014787:Vision Tests; D014792:Visual Acuity
keywords: population-based survey; refractive error; rural area; school-aged; spectacle correction