title: Prevalence of myopia among 12- to 13-year-old schoolchildren in northern Mexico.
abstract: OBJECTIVE
  The aim of this article was to report the prevalence of refractive errors, mainly myopia, among 12- to 13-year-old children in a metropolitan setting in Mexico.
  
  
  METHODS
  A total of 1035 schoolchildren were examined in a field study in Monterrey, Mexico. The examination included best-corrected visual acuity and refraction during cycloplegia. A sample of the children was sent to a pediatric eye clinic and underwent cycloplegic refraction with an autorefractor.
  
  
  RESULTS
  We found a prevalence of myopia (>/=-0.5 D SE) of 44%, whereas bilateral myopia was present in 37% of the children. In the total sample, high myopia (>/=-5D) was found in 1.4%. The prevalence of myopia was significantly higher in girls. Only 20% of children with bilateral myopia used prescription glasses; 8% had prescribed glasses, but did not use them. Hyperopia (>/=+1 D) was present in 6.0% of the total population, and astigmatism (>/=-1.5 D) was present in 9.5%.
  
  
  CONCLUSIONS
  The prevalence of myopia among 12- to 13-year-old children in Mexico is high. The majority of cases are low grade, and a large number of the myopic children do not have, or do not use, prescription glasses.
authors.affiliation: Department of Ophthalmology, Universidad Autónoma de Neuvo León, Monterrey, Mexico.
authors.forename: Gerardo M
authors.initials: GM
authors.lastname: Villarreal
authors.forename: Josefin
authors.initials: J
authors.lastname: Ohlsson
authors.forename: Humberto
authors.initials: H
authors.lastname: Cavazos
authors.forename: Maths
authors.initials: M
authors.lastname: Abrahamsson
authors.forename: Jesus H
authors.initials: JH
authors.lastname: Mohamed
mesh_terms: D000293:Adolescent; D002648:Child; D005139:Eyeglasses / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D009216:Myopia / Q000453:epidemiology* / Q000628:therapy; D015995:Prevalence; D012029:Refraction, Ocular; D012574:Schools; D014792:Visual Acuity