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Subjective Refraction Test Using a Smartphone for Vision Screening
Published on: October 18, 2024
Effective refractive error coverage and vision impairment among schoolchildren in Xinjiang, China
Fangfang Lu1, Hongwen Jiang2, Waihang Wong1
1State Key Laboratory of Ophthalmology; Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science; Guangdong Provincial Clinical Research Center for Ocular Disease, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China.
Background:
Uncorrected refractive error (URE) is the leading cause of vision impairment (VI). Effective refractive error coverage (eREC) is a WHO-endorsed indicator for tracking the global eyecare progress; however, there is a lack of reliable eREC estimate for children due to a paucity of available data. This study aimed to estimate the eREC and prevalence of VI among schoolchildren in Xinjiang, China.
Methods:
A population-based, cross-sectional study was conducted among schoolchildren aged 7-20 years from May to June 2024. Uniocular uncorrected, presenting and best-corrected visual acuity was measured using standard logarithmic vision charts per standardised protocol, and refractive error coverage indicators (eREC, refractive error coverage (REC) and Quality Gap) were calculated according to WHO definitions. Sociodemographic correlates of eREC and REC were assessed using multivariable logistic regression analysis.
Results:
A total of 3306 children were examined (mean age, 12.5±2.3 years; 50.03% boys). The prevalence of VI based on uncorrected, presenting and best-corrected visual acuity was 8.74%, 4.30% and 0.15%, respectively. The overall eREC and REC were 51.76% and 54.93%, with a quality gap of 5.77%. Age and sex did not show a significant association with eREC, whereas secondary school education (vs primary school education, OR=3.59, 95% CI 1.52 to 9.29, p=0.005) was significantly associated with a higher eREC.
Conclusion:
96.51% of VI were due to URE among school-aged children in Xinjiang, China. The eREC remains well below the WHO 2030 global target for China, highlighting the need to improve both the accessibility and quality of refractive correction in this population.
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