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Refractive Error and Visual Function in Children Under Non-cycloplegic Screening Conditions
Ana Roque1,2, Amélia Fernandes Nunes2, Henrique Nascimento1
1School of Administration, Engineering and Aeronautics (EGEA), Instituto Superior de Educação e Ciências de Lisboa (ISEC Lisboa), Alameda das Linhas de Torres, Lisboa, Portugal.
Journal of Primary Care & Community Health
|July 3, 2026
Summary
Visual acuity screening in children may not accurately reflect refractive errors, especially low-level ones. Many children with refractive errors had normal visual acuity, indicating potential gaps in current vision screening methods.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Vision Science
Background:
- Refractive errors and reduced uncorrected visual acuity (UCVA) are common in children.
- Assessing the relationship between UCVA and refractive status is crucial for effective vision screening.
Purpose of the Study:
- To determine the prevalence of refractive error and reduced UCVA in children.
- To evaluate how well UCVA reflects refractive status in conditions mimicking primary care and school vision screenings.
Main Methods:
- Cross-sectional study of 190 children (mean age 8.35 years) in Lisbon, Portugal.
- Non-cycloplegic retinoscopy for refractive status and logMAR charts for UCVA measurement.
- Multivariable logistic regression to identify factors associated with reduced UCVA.
Main Results:
- Hyperopia was most prevalent (56.8%), followed by emmetropia (22.6%) and myopia (20.5%), with a trend towards myopia with age.
- Reduced UCVA was observed in 30.5% of children, increasing with age; many were uncorrected.
- A significant proportion of children with refractive error had normal UCVA (68.7%), and some without refractive error showed reduced UCVA (6.3%).
Conclusions:
- In this pediatric sample, UCVA alone may not reliably indicate refractive status under routine, non-cycloplegic screening conditions.
- Findings suggest limitations in using visual acuity as the sole indicator for refractive errors, particularly low-magnitude ones.
- Results from this clinical sample should be generalized cautiously due to the non-population-based nature of the participants.
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