title: Prevalence and causes of blindness in the South Australian population aged 50 and over.
abstract: OBJECTIVE
  To conduct a population based study examining the prevalence and causes of blindness and visual impairment in the South Australian population aged 50 and over.
  
  
  METHODS
  A random stratified cluster sample of 2115 persons was recruited from geographically exhaustive local government areas within South Australia. All participants underwent distance visual acuity measurements. In those participants with corrected visual acuity < 6/18 in the better eye a cause was determined.
  
  
  RESULTS
  Cataract and macular degeneration were the most common causes of monocular and binocular blindness. The prevalence of monocular and binocular blindness in South Australia in the population aged 50 and over is calculated to be approximately 3.7% and 1.3%, respectively. These rates increase significantly in the elderly (70 years of age and over) subgroups.
  
  
  CONCLUSIONS
  Degenerative conditions are the principal causes of visual impairment in South Australia. The number of visually impaired persons in South Australia is likely to increase over the coming decades. Accurate data are essential in order to optimise the use of limited resources.
authors.affiliation: Dept. Ophthalmol., Royal Adelaide Hospital, Australia.
authors.forename: H S
authors.initials: HS
authors.lastname: Newland
authors.forename: J E
authors.initials: JE
authors.lastname: Hiller
authors.forename: R J
authors.initials: RJ
authors.lastname: Casson
authors.forename: S
authors.initials: S
authors.lastname: Obermeder
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001766:Blindness / Q000453:epidemiology* / Q000209:etiology* / Q000503:physiopathology; D002386:Cataract / Q000150:complications / Q000503:physiopathology; D005260:Female; D006801:Humans; D008268:Macular Degeneration / Q000150:complications / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D015995:Prevalence; D011897:Random Allocation; D017678:Sex Distribution; D013021:South Australia / Q000453:epidemiology; D014792:Visual Acuity