title: The prevalence of refractive errors among adults in the United States, Western Europe, and Australia.
abstract: OBJECTIVE
  To estimate the prevalence of refractive errors in persons 40 years and older.
  
  
  METHODS
  Counts of persons with phakic eyes with and without spherical equivalent refractive error in the worse eye of +3 diopters (D) or greater, -1 D or less, and -5 D or less were obtained from population-based eye surveys in strata of gender, race/ethnicity, and 5-year age intervals. Pooled age-, gender-, and race/ethnicity-specific rates for each refractive error were applied to the corresponding stratum-specific US, Western European, and Australian populations (years 2000 and projected 2020).
  
  
  RESULTS
  Six studies provided data from 29 281 persons. In the US, Western European, and Australian year 2000 populations 40 years or older, the estimated crude prevalence for hyperopia of +3 D or greater was 9.9%, 11.6%, and 5.8%, respectively (11.8 million, 21.6 million, and 0.47 million persons). For myopia of -1 D or less, the estimated crude prevalence was 25.4%, 26.6%, and 16.4% (30.4 million, 49.6 million, and 1.3 million persons), respectively, of whom 4.5%, 4.6%, and 2.8% (5.3 million, 8.5 million, and 0.23 million persons), respectively, had myopia of -5 D or less. Projected prevalence rates in 2020 were similar.
  
  
  CONCLUSIONS
  Refractive errors affect approximately one third of persons 40 years or older in the United States and Western Europe, and one fifth of Australians in this age group.
authors.affiliation: Johns Hopkins University School of Medicine, 550 N. Broadway, Suite 700, Baltimore, MD 21205, USA.
authors.forename: John H
authors.initials: JH
authors.lastname: Kempen
authors.forename: Paul
authors.initials: P
authors.lastname: Mitchell
authors.forename: Kristine E
authors.initials: KE
authors.lastname: Lee
authors.forename: James M
authors.initials: JM
authors.lastname: Tielsch
authors.forename: Aimee T
authors.initials: AT
authors.lastname: Broman
authors.forename: Hugh R
authors.initials: HR
authors.lastname: Taylor
authors.forename: M Kamran
authors.initials: MK
authors.lastname: Ikram
authors.forename: Nathan G
authors.initials: NG
authors.lastname: Congdon
authors.forename: Benita J
authors.initials: BJ
authors.lastname: O'Colmain
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia / Q000453:epidemiology; D044383:Black People / Q000706:statistics & numerical data*; D005060:Europe / Q000453:epidemiology; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012030:Refractive Errors / Q000208:ethnology*; D017678:Sex Distribution; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data*; D001741:Black or African American