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Refractive error and visual impairment in school children in Northern Ireland
  1. L O'Donoghue1,
  2. J F McClelland1,
  3. N S Logan2,
  4. A R Rudnicka3,
  5. C G Owen3,
  6. K J Saunders1
  1. 1School of Biomedical Sciences, University of Ulster, Coleraine, UK
  2. 2Aston University, Ophthalmic Research Group, Birmingham, UK
  3. 3St George's, University of London, London, UK
  1. Correspondence toDr Lisa O'Donoghue, School of Biomedical Sciences, University of Ulster, Cromore Road, Coleraine, BT52 1SA, UK; l.odonoghue{at}


Aims To describe the prevalence of refractive error (myopia and hyperopia) and visual impairment in a representative sample of white school children.

Methods The Northern Ireland Childhood Errors of Refraction study, a population-based cross-sectional study, examined 661 white 12–13-year-old and 392 white 6–7-year-old children between 2006 and 2008. Procedures included assessment of monocular logarithm of the minimum angle of resolution (logMAR), visual acuity (unaided and presenting) and binocular open-field cycloplegic (1% cyclopentolate) autorefraction. Myopia was defined as −0.50DS or more myopic spherical equivalent refraction (SER) in either eye, hyperopia as ≥+2.00DS SER in either eye if not previously classified as myopic. Visual impairment was defined as >0.30 logMAR units (equivalent to 6/12).

Results Levels of myopia were 2.8% (95% CI 1.3% to 4.3%) in younger and 17.7% (95% CI 13.2% to 22.2%) in older children: corresponding levels of hyperopia were 26% (95% CI 20% to 33%) and 14.7% (95% CI 9.9% to 19.4%).

The prevalence of presenting visual impairment in the better eye was 3.6% in 12–13-year-old children compared with 1.5% in 6–7-year-old children. Almost one in four children fails to bring their spectacles to school.

Conclusions This study is the first to provide robust population-based data on the prevalence of refractive error and visual impairment in Northern Irish school children. Strategies to improve compliance with spectacle wear are required.

  • Myopia
  • hyperopia
  • refractive error
  • visual impairment
  • vision
  • optics and refraction
  • public health
  • epidemiology
  • child health (paediatrics)

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  • Funding College of Optometrists, 42 Craven Street, London WC2N 5NG;Northern Ireland Optometric Society, PO Box 28, Dromore BT25 1YH.

  • Competing interests None.

  • Ethics approval This study was conducted with the approval of the University of Ulster Research Ethics Committee.

  • Provenance and peer review Not commissioned; externally peer reviewed.

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