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An Automated Method for Assessing Visual Acuity in Infants and Toddlers Using an Eye-Tracking System
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The electronic visual acuity tester: testability in preschool children
Insights
This study shows that nearly all preschool children aged 3.5 to 5 years can complete visual acuity testing using a computer-based system. The Electronic Visual Acuity tester proved effective for assessing vision in young children.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Vision Science
Background:
- Assessing visual acuity in preschool children is crucial for early detection of vision impairments.
- Traditional methods can be challenging with young children, necessitating standardized, child-friendly approaches.
Purpose of the Study:
- To evaluate the efficacy of a computer-based letter test for assessing threshold visual acuity in preschool children.
- To determine the testability rates of young children using the Electronic Visual Acuity (EVA) tester.
Main Methods:
- 1195 children aged 3.5 to 5 years participated in the Vision in Preschoolers Study.
- Licensed eye care professionals administered tests using the EVA tester with letters H, O, T, V and a crowded surround.
- Monocular visual acuity was assessed after successful training and pretesting phases.
Main Results:
- 99.1% of children successfully completed letter identification training.
- 97.6% of those who passed training and pretesting completed monocular visual acuity testing.
- Testability increased with age, with 98.8% of 5-year-olds completing all testing stages.
Conclusions:
- The computer-based Electronic Visual Acuity system is highly effective for assessing monocular visual acuity in preschool children aged 3.5 to 5 years.
- The EVA system demonstrates high completion rates, indicating its suitability for pediatric vision screening.
Purpose:
To evaluate the ability of preschool children to have their threshold visual acuity assessed using a standardized, computer-based letter test.
Methods:
Participants were 1195 3.5- to 5-year-old children enrolled in the Vision in Preschoolers Study. Monocular visual acuity was assessed by licensed eye care professionals (optometrists and pediatric ophthalmologists experimented in the examination of children), using the Electronic Visual Acuity tester, which uses the letters H, O, T, and V with a crowded surround.
Results:
Overall, 99.1% of children passed the training that consisted of identifying the letters H, O, T, and V by naming or matching the letters at 60 cm. Among those who passed the training, 99.6% completed the binocular pretest at 3 m, and 97.6% of those passing the training and the pretest completed monocular threshold visual acuity testing of each eye with the Electronic Visual Acuity tester. Testability increased with age for training (p = 0.03), pretesting (p = 0.04), and acuity testing (p = 0.07). Overall, 93.3% of 3.5-year-olds, 96.7% of 4-year-olds, and 98.8% of 5-year-olds completed training, pretesting, and monocular threshold acuity testing of each eye using standard letter optotypes.
Conclusion:
Using the computer-based Electronic Visual Acuity system, nearly all 3.5- to 5-year-old children can complete monocular acuity testing of each eye.
