Prevalence of Refractive Errors in Singapore Chinese Children Aged 6 to 72 Months

Abstract

Purpose: : To determine the age-specific prevalence of refractive error in Singapore Chinese children aged 6 to 72 months in the Strabismus, Amblyopia and Refractive error in Singaporean Children (STARS) study.

Methods: : A population-based survey was conducted in the South-Western region of Singapore. Disproportionate random sampling by 6 month age groups of Chinese children aged 6 to 72 months was performed. Participants underwent cycloplegic refraction (3 drops of 1% cyclopentolate) by trained eye care professionals using the table-mounted autorefractor Canon RK-F1 in children aged 30 months and above, hand-held Nikon Retinomax K-Plus 2 in children aged 30 months and below and retinoscopy, if reliable retinomax readings could not be obtained. The overall and age-specific prevalence of myopia (SE at least -0.5 Diopters [D]), high myopia (SE at least -6.0 D), hyperopia (SE at least +3.0 D), astigmatism (cylinder at least 1.5 D) and anisometropia (SE difference of at least 2.0D between the two eyes) were calculated.

Results: : Of the 3009 children (participation rate=72.3%) participated, right eye data from 2639 children who agreed to cycloplegic eye drops were included in this analysis. The mean right eye spherical equivalent was +0.69 (SD = 1.15). The overall prevalence of myopia was 11.0%. The prevalence of high myopia was 0.2%. The prevalence of hyperopia, astigmatism and anisometropia were 1.4%, 8.6% and 0.6%, respectively. Myopia rates were 15.8%, 14.9%, 20.2%, 8.6%, 7.6%, and 6.4% in children aged 6-11, 12-23, 24-35, 36-47, 48-59, and 60-72 months old. The rates did not vary between boys (11.3%) and girls (11.5%) (p=0.91). The prevalence of astigmatism increased with age (p<0.001), but the prevalence of hyperopia and anisometropia did not vary with age.

Conclusions: : The prevalence of myopia in young Singapore Chinese aged 6 to 72 months is high and hyperopia low. The high prevalence of myopia in children below 36 months needs further evaluation.

Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • myopia • refractive error development