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Prevalence of uncorrected refractive error in low-resource high schools in the Free State, South Africa
Xolani Nyathela1, Urvashni Nirghin, Naimah Ebrahim Khan
1Department of Optometry, Faculty of Health Sciences, University of KwaZulu-Natal, Durban. 222059728@stu.ukzn.ac.za.
Background:
The continuous increase in the prevalence of refractive error (RE) globally, with uncorrected refractive error (URE) having been established as the leading cause of visual impairment (VI) in children, is a public health concern. Previous RE studies in South Africa also indicated a growing prevalence, substantiating the burden on schoolchildren.
Aim:
To determine the prevalence of URE among high school learners.
Setting:
No-fee-paying high schools in the Free State, South Africa.
Methods:
A school-based cross-sectional study design was conducted on 13- to 19-year-old learners through a multistage stratified random method. The examination included an unaided logarith of the minimum angle of resolution (LogMAR) visual acuity test, binocular motor alignment tests, ocular health assessment and cycloplegic autorefraction.
Results:
A total of 868 learners consented to participate in this study, with a mean age of 16.4 ± 1.7 years. Male participants accounted for 34.5% (n = 299), while female participants accounted for 65.6% (n = 569), with the majority being Grade 10 learners. The prevalence of URE stood at 27.1% (n = 233), with astigmatism being the most prevalent ametropia, accounting for 22.3% (192 cases), followed by myopia at 15.1% (n = 130) and hyperopia at 5.4% (n = 46).
Conclusion:
A high prevalence of URE, especially among older participants, was established, prompting an urgent concerted intervention from all stakeholders to curb the scourge.Contribution: This study accentuates the visual situation of vulnerable learners, that is, older children from disadvantaged backgrounds in the Free State, which until this point had not been established.
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