title: Prevalence of blindness and low vision: a study in the rural Heilongjiang Province of China.
abstract: BACKGROUND
  The prevalence of blind individuals in the north of China is unknown. The study aimed to investigate the prevalence and causes of blindness and low vision in rural areas in Heilongjiang province of China in 2008-2009.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  A cluster random sampling method was used to recruit participants of all ages in rural areas of Heilongjiang.
  
  
  METHODS
  Trained professionals performed interviews and clinical examinations to measure visual acuity. The relationships between blindness or low vision and age, gender and education level were analysed.
  
  
  METHODS
  The main outcome measure was prevalence rates of bilateral blindness and bilateral low vision.
  
  
  RESULTS
  Of the 11 787 subjects, 10 384 (88.1%) were surveyed. The overall age-adjusted prevalence rates were 0.7% (95% confidence interval: 0.5-0.8%) for bilateral blindness and 1.7% (95% confidence interval: 1.4-1.9%) for bilateral low vision. The prevalence rates of blindness and low vision were higher in the elderly and uneducated population (P < 0.05). The main causes for blindness and low vision were cataracts (44.1 and 46.0%, respectively) and refractive errors (17.7 and 42.5%, respectively).
  
  
  CONCLUSIONS
  Blindness and low vision are highly prevalent among people with cataracts and refractive errors. Eye care planning must focus on treating the avoidable and curable forms of blindness.
authors: The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Harbin, China.
authors: Yaoguang
authors: Y
authors: Zhang
authors: Haijing
authors: H
authors: Wang
authors: Jianju
authors: J
authors: Liu
authors: Tiebin
authors: T
authors: Wang
authors: Shujie
authors: S
authors: Cao
authors: Dan
authors: D
authors: Zhou
authors: Lingling
authors: L
authors: Du
authors: Zhisheng
authors: Z
authors: Li
authors: Ping
authors: P
authors: Liu
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001766:Blindness / Q000453:epidemiology*; D002386:Cataract / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011786:Quality Control; D012030:Refractive Errors / Q000453:epidemiology; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data*; D017678:Sex Distribution; D015354:Vision, Low / Q000453:epidemiology*; D014792:Visual Acuity / Q000502:physiology; D019987:Persons with Visual Disabilities / Q000706:statistics & numerical data*; D055815:Young Adult