Prevalence of refractive error among preschool children in an urban population: the Baltimore Pediatric Eye Disease Study

Ophthalmology. 2009 Apr;116(4):739-46, 746.e1-4. doi: 10.1016/j.ophtha.2008.12.030. Epub 2009 Feb 25.


Purpose: To determine the age-specific prevalence of refractive errors in white and African-American preschool children.

Design: The Baltimore Pediatric Eye Disease Study is a population-based evaluation of the prevalence of ocular disorders in children aged 6 to 71 months in Baltimore, Maryland.

Participants: Among 4132 children identified, 3990 eligible children (97%) were enrolled and 2546 children (62%) were examined.

Methods: Cycloplegic autorefraction was attempted in all children with the use of a Nikon Retinomax K-Plus 2 (Nikon Corporation, Tokyo, Japan). If a reliable autorefraction could not be obtained after 3 attempts, cycloplegic streak retinoscopy was performed.

Main outcome measures: Mean spherical equivalent (SE) refractive error, astigmatism, and prevalence of higher refractive errors among African-American and white children.

Results: The mean SE of right eyes was +1.49 diopters (D) (standard deviation [SD] = 1.23) in white children and +0.71 D (SD = 1.35) in African-American children (mean difference of 0.78 D; 95% confidence interval [CI], 0.67-0.89). Mean SE refractive error did not decline with age in either group. The prevalence of myopia of 1.00 D or more in the eye with the lesser refractive error was 0.7% in white children and 5.5% in African-American children (relative risk [RR], 8.01; 95% CI, 3.70-17.35). The prevalence of hyperopia of +3 D or more in the eye with the lesser refractive error was 8.9% in white children and 4.4% in African-American children (RR, 0.49; 95% CI, 0.35-0.68). The prevalence of emmetropia (<-1.00 D to <+1.00 D) was 35.6% in white children and 58.0% in African-American children (RR, 1.64; 95% CI, 1.49-1.80). On the basis of published prescribing guidelines, 5.1% of the children would have benefited from spectacle correction. However, only 1.3% had been prescribed correction.

Conclusions: Significant refractive errors are uncommon in this population of urban preschool children. There was no evidence for a myopic shift over this age range in this cross-sectional study. A small proportion of preschool children would likely benefit from refractive correction, but few have had this prescribed.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • African Americans
  • Baltimore / epidemiology
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • European Continental Ancestry Group
  • Female
  • Humans
  • Infant
  • Male
  • Mydriatics / administration & dosage
  • Prevalence
  • Pupil / drug effects
  • Refraction, Ocular
  • Refractive Errors / epidemiology*
  • Retinoscopy
  • Urban Population / statistics & numerical data*
  • Vision Tests


  • Mydriatics