Patterns of spectacle use in young Australian school children: Findings from a population-based study

Purpose: To describe the patterns of spectacle use in a population-based sample of Australian Year 1 school children (mostly aged 6 years). Methods: Logarithm of the minimum angle of resolution (logMAR) visual acuity was measured in both eyes before and after pinhole correction, and using spectacles if worn. Cycloplegic autorefraction (cyclopentolate) and detailed dilated fundus examination were performed. Visual impairment was defined as visual acuity < 40 logMAR letters (ie, < 20/40 Snellen equivalent). Myopia was defined as spherical equivalent (SE) refraction <= -0.50 diopters (D), and hyperopia as SE refraction >= +2.0D, deemed significant when >= +3.0D. Astigmatism was defined as cylinder >= 1.0D and anisometropia as SE refraction difference between the two eyes at least 1.0D. Results: One thousand seven hundred forty predominantly 6-year-old school children were examined during 2003 to 2004. Spectacle use was documented in 77 children (4.4% of sample). Uncorrected visual impairment was found in the worse eye of 71 children (4.1%) and refractive error accounted for the majority (69.0%). Astigmatism was the most common refractive error causing visual impairment, accounting for 46.5%. Hyperopia, with or without astigmatism, was the most frequent reason for spectacle use, documented in 40.3%. Spectacle use in the absence of significant refractive error, amblyogenic risk factors, or visual impairment was noted in 26 children (33.8% of spectacle wearers). The prescription of spectacles could have benefited a further 26 children (1.5% of sample), mostly for correction of astigmatism. Conclusion: This study documents a significant disparity between spectacle use and need. Astigmatism was the most common cause of visual impairment due to refractive error.