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$Subjective Refraction Test Using a Smartphone for Vision Screening$

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Published on: October 18, 2024

Refractive errors in low-income preschoolers.

Barbara L Brody¹, Anne-Catherine Roch-Levecq, Hillary S Klonoff-Cohen

¹Department of Ophthalmology (SIB), Division of Community Ophthalmology (A-CR-L & BLB), University of California, San Diego, La Jolla, California 92093-0946, USA.

Ophthalmic Epidemiology

|September 27, 2007

Summary

Refractive errors affect 16% of low-income preschoolers, with hyperopia and astigmatism being most common. Early detection of vision problems in children is crucial for development.

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Area of Science:

Ophthalmology
Pediatric Optometry
Public Health

Background:

Refractive errors are a significant cause of vision impairment in children.
Early identification and management of refractive errors are essential for optimal visual development and academic success.
Preschool-aged children, particularly those from low-income backgrounds, may have limited access to regular vision screenings.

Purpose of the Study:

To determine the prevalence of refractive errors in a population of low-income preschoolers in San Diego County.
To identify the types and frequencies of specific refractive errors within this demographic.

Main Methods:

A cross-sectional study involving 507 preschool children (ages 3-5) from low-income families in San Diego County.
Comprehensive eye examinations including retinoscopy under cycloplegia were performed by optometrists.
Refractive errors were defined using specific diopter (D) thresholds for myopia, hyperopia, astigmatism, and anisometropia, with age-specific criteria.

Main Results:

Overall, 16% of the preschool children exhibited refractive errors in at least one eye.
Hyperopia was diagnosed in 7.5% of children, astigmatism in 5.5%, and myopia in 3%.
The majority of children (84%) were classified as emmetropic, with minimal refractive error.

Conclusions:

Hyperopia and astigmatism were the most prevalent refractive errors identified in this low-income preschool population.
The findings highlight the importance of vision screening in preschool children, especially those from underserved communities.
A significant proportion of children required intervention for refractive errors, underscoring the need for accessible eye care services.