title: Refractive error among the elderly in rural Southern Harbin, China.
abstract: OBJECTIVE
  To estimate the prevalence and associated factors of refractive errors among the elderly in a rural area of Southern Harbin, China.
  
  
  METHODS
  Five thousand and fifty seven subjects (age > or = 50 years) were enumerated for a population-based study. All participants underwent complete ophthalmic evaluation. Refraction was performed by ophthalmic personnel trained in the study procedures. Myopia was defined as spherical equivalent worse than -0.50 diopters (D) and hyperopia as spherical equivalent worse than +0.50 D. Astigmatism was defined as a cylindrical error worse than 0.75D. Association of refractive errors with age, sex, and education were analyzed.
  
  
  RESULTS
  Of the 5,057 responders (91.0%), 4,979 were eligible. The mean age was 60.5 (range 50-96) years old. The prevalence of myopia was 9.5% (95% confidence interval [CI], 8.5-10.1) and of hyperopia was 8.9% (95% CI, 7.9-9.5). Astigmatism was evident in 7.6% of the subjects. Myopia, hyperopia and astigmatism increased with increasing age (p<0.001, respectively). Myopia and astigmatism were more common in males, whereas hyperopia was more common in females. We also found that prevalence of refractive error weas associated with education. Myopia was more common in those with higher degrees of education, whereas hyperopia and astigmatism were more common in those with no formal education.
  
  
  CONCLUSIONS
  This report has provided details of the refractive status in a rural population of Harbin. The prevalence of refractive errors in this population is lower than those reported in other regions of the world.
authors.affiliation: Department of Ophthalmology, First Affiliated Hospital, Harbin Medical University, Harbin, China. lzj6515@sina.com
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Li
authors.forename: Dianjun
authors.initials: D
authors.lastname: Sun
authors.forename: Hao
authors.initials: H
authors.lastname: Cuj
authors.forename: Liqiong
authors.initials: L
authors.lastname: Zhang
authors.forename: Ping
authors.initials: P
authors.lastname: Lju
authors.forename: Hongbin
authors.initials: H
authors.lastname: Yang
authors.forename: Jie
authors.initials: J
authors.lastname: Baj
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D005260:Female; D006302:Health Services Research; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012030:Refractive Errors / Q000453:epidemiology*; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data*; D017678:Sex Distribution; D014792:Visual Acuity