title: Amblyopia risk factor prevalence.
abstract: OBJECTIVE
  In 2003, the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) published a set of risk factors for amblyopia. The intent was to promote uniformity of reporting and development in screening. Because this prevalence is not yet known, this meta-analysis is an attempt to estimate it.
  
  
  METHODS
  Major community preschool eye examination studies were reviewed and AAPOS cut-offs estimated.
  
  
  RESULTS
  The approximate prevalence of anisometropia is 1.2%, hyperopia is 6%, astigmatism is 15%, myopia is 0.6%, strabismus is 2.5%, and visual acuity less than 20/40 is 6%. The mean combined prevalence is 21% ± 2% compared to a prevalence of amblyopia 20/40 and worse of 2.5%.
  
  
  CONCLUSIONS
  Knowing risk factor prevalence simplifies validation efforts. Amblyopia screening with a risk factor sensitivity less than 100% is expected and desirable.
authors.affiliation: Alaska Blind Child Discovery, Anchorage, AK 99501, USA. eyedoc@alaska.net
authors.forename: Robert W
authors.initials: RW
authors.lastname: Arnold
mesh_terms: D000550:Amblyopia / Q000453:epidemiology*; D015858:Anisometropia / Q000453:epidemiology; D001251:Astigmatism / Q000453:epidemiology; D002675:Child, Preschool; D006801:Humans; D006956:Hyperopia / Q000453:epidemiology; D009216:Myopia / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D013285:Strabismus / Q000453:epidemiology; D014792:Visual Acuity