title: Prevalence and Causes of Visual Impairment and Blindness in Shanxi Province, China.
abstract: OBJECTIVE
  To estimate the prevalence and causes of visual impairment and blindness in Shanxi Province, China.
  
  
  METHODS
  Data were obtained from the Second National Sampling Survey of Disability conducted in 2006. Blindness and visual impairment were defined as best corrected visual acuity <3/60 and <6/18, respectively, in the better-seeing eye. Standardized ophthalmologic examinations were administered to participants aged 0-80 years in 2006. Visual acuity (VA) was measured using a Standard Logarithmic Visual Acuity E chart (Snellen) for subjects aged 7 years and older. Participants younger than 7 years were examined using special experiments or the Childhood Graphical Visual Chart.
  
  
  RESULTS
  The prevalence of visual impairment and blindness in Shanxi was estimated to be 0.6% (466/75,016) among persons up to 80 years old. The prevalence in rural areas (0.7%; 351/48,137) was significantly higher than that in urban areas (0.4%; 115/26,879) and was higher in females (0.8%; 298/36,933) than in males (0.4%; 168/38,083). The most common cause of visual impairment and blindness was cataract (44.9%), followed by retinopathy and choroidopathy (12.5%), hereditary and developmental disorders (10.3%), corneal disease (5.2%), and refractive error (4.9%).
  
  
  CONCLUSIONS
  Prevalences of visual impairment and blindness in women and in rural areas were higher than in men and urban areas, and increased with age. Cataract was the most prevalent cause of visual impairment and blindness. Based on the findings from this study, we suggest that provision of support and welfare services should be organized.
authors.affiliation: Department of Ophthalmology, The Second Hospital of Shanxi Medical University , Taiyuan , China.
authors.forename: Tong
authors.initials: T
authors.lastname: Li
authors.forename: Liping
authors.initials: L
authors.lastname: Du
authors.forename: Lingzhen
authors.initials: L
authors.lastname: Du
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001766:Blindness / Q000453:epidemiology* / Q000209:etiology*; D002386:Cataract / Q000150:complications / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D015862:Choroid Diseases / Q000150:complications / Q000453:epidemiology; D003316:Corneal Diseases / Q000150:complications / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012030:Refractive Errors / Q000150:complications / Q000453:epidemiology; D012164:Retinal Diseases / Q000150:complications / Q000453:epidemiology; D012424:Rural Population / Q000706:statistics & numerical data; D017678:Sex Distribution; D014505:Urban Population / Q000706:statistics & numerical data; D014792:Visual Acuity / Q000502:physiology; D019987:Persons with Visual Disabilities / Q000706:statistics & numerical data*
keywords: Blindness; China; Shanxi Province; causes; prevalence; visual impairment