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Updated: Jan 24, 2026

Subjective Refraction Test Using a Smartphone for Vision Screening
Published on: October 18, 2024
Prevalence of refractive error and spectacle coverage in schoolchildren in two urban areas of Chile
Fernando Barria1, Francisco Conte2, Sergio Muñoz3
1Regional Hospital, Universidad de Concepción, Concepción, Chile.
Objective:
To assess the impact of efforts to reduce visual impairment by detecting and treating refractive errors (REs) among schoolchildren in two urban areas of Chile.
Methods:
In 2013, in the communities of Concepción and La Florida, we conducted a multicenter, multistage-sampling, cross-sectional study employing methods used by the Refractive Error Study in Children (RESC) survey. Best-corrected visual acuity was assessed using pinhole, with and without glasses. The coverage for correcting visual impairment due to refractive error was estimated.
Results:
We examined 5 412 schoolchildren, in the communities of Concepción (n = 3 049) and La Florida (n = 2 363). Uncorrected visual acuity (VA) of > 0.63 in at least one eye was found in 4 721 children (87.23%; 95% confidence interval (CI): 86.58%-88.30%). Of the remaining children, 1 017 of them (18.79%; 95% CI: 17.78%-19.80%) had a VA of < 0.5 in at least one eye. Of the 691 children with uncorrected visual impairment with both eyes open (12.77%; 95% CI: 11.9%-13.64%), 476 of them (8.76%; 95% CI: 8.03%-9.49%) achieved normal vision using best possible correction, and with 271 of the 476 (56.93%) having a normal presenting VA in the better eye.
Conclusions:
We found an increased coverage of services for RE-associated visual impairment and an increased percentage of children wearing glasses as compared to values reported for La Florida in an article published in 2000. The National Board of School Aid and Scholarships (JUNAEB) in Chile is achieving better results in its schoolchildren eye care program.
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