title: Inferring myopia over the lifecourse from uncorrected distance visual acuity in childhood.
abstract: OBJECTIVE
  To report the usefulness of uncorrected distance visual acuity (DVA) at 16 years to "screen" for myopia status and to assess the lifetime risk of myopia, based on a national birth cohort.
  
  
  METHODS
  1867 members of the 1958 British birth cohort for whom there were data on acuity at 16 years had autorefraction, as part of a biomedical survey, at 45 years. Reduced uncorrected DVA at age 16 years (6/12 or worse in both eyes) was compared with adult refraction (spherical equivalent).
  
  
  RESULTS
  Only a quarter of individuals in the population studied who had developed myopia by 45 years of age had reduced acuity at 16 years of age. Notably, half of all adults with moderate myopia (-2.99 to -5.99) and 31% (11/35) with severe myopia (> or =-6) had good uncorrected DVA in both eyes at 16 years of age. Thus, sensitivities were low, ranging from 16% for all myopia (cut-off point spherical equivalent -0.5) to 69% for severe myopia (cut-off point spherical equivalent -6). However, a high (91%) lifetime probability of primary myopia (spherical equivalent > or =-0.5) given a reduced uncorrected DVA at 16 years was found.
  
  
  CONCLUSIONS
  In this population, reduced uncorrected DVA in childhood is an inaccurate and inappropriate intermediate "phenotype" for capturing adult myopia status. However, our findings support assessment of DVA in secondary school children as an effective method of identifying refractive error (both myopia and hypermetropia).
authors.affiliation: Centre for Paediatric Epidemiology and Biostatistics, Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK.
authors.forename: Phillippa M
authors.initials: PM
authors.lastname: Cumberland
authors.forename: Catherine S
authors.initials: CS
authors.lastname: Peckham
authors.forename: Jugnoo S
authors.initials: JS
authors.lastname: Rahi
mesh_terms: D000293:Adolescent; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D011379:Prognosis; D012029:Refraction, Ocular; D012680:Sensitivity and Specificity; D006113:United Kingdom / Q000453:epidemiology; D015351:Vision Screening / Q000379:methods*; D014792:Visual Acuity