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Updated: Jun 23, 2026
An Automated Method for Assessing Visual Acuity in Infants and Toddlers Using an Eye-Tracking System
Published on: March 17, 2023
Visual acuity norms in pre-school children: the Multi-Ethnic Pediatric Eye Disease Study
Ying Pan1, Kristina Tarczy-Hornoch, Susan A Cotter
1Department of Ophthalmology, MPH Doheny Eye Institute, University of Southern California, Los Angeles, California 90033, USA.
Insights
Visual acuity (VA) improves with age in young children. New age-specific thresholds for defining abnormal VA in children aged 2-5 years are proposed for screening and clinical practice.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Public Health
Background:
- Establishing normative data for visual acuity (VA) and interocular differences (IOD) is crucial for identifying visual impairments in children.
- Previous studies have focused on limited age ranges or specific ethnic groups, necessitating broader population-based data.
Purpose of the Study:
- To provide population-based normative data for monocular visual acuity (VA) and interocular differences in VA (IOD) in Black and Hispanic children aged 30 to 72 months.
- To establish age-specific thresholds for defining abnormal VA in preschool-aged children without significant refractive errors or ophthalmic abnormalities.
Main Methods:
- Analysis of monocular HOTV VA measurements from the Multi-Ethnic Pediatric Eye Disease Study cohort.
- Inclusion of 1722 Black and Hispanic children aged 30 to 72 months, excluding those with ophthalmic abnormalities or refractive errors.
- Statistical analysis of continuous and dichotomous outcomes for VA and IOD, examining associations with age, ethnicity, and gender.
Main Results:
- Mean logMAR VA improved with age and was better in males.
- The proportion of children achieving VA 20/40 or better increased significantly with age, reaching nearly 100% by 60-72 months.
- Age-specific stringent VA thresholds were identified, with 6% of normal children having an IOD of 2 or more lines.
Conclusions:
- Visual acuity test performance in normal preschool children significantly improves with age.
- New age-specific thresholds for defining abnormal monocular VA using HOTV optotypes are proposed for children aged 2-5 years.
- These proposed thresholds can aid in screening, clinical practice, and research for early detection of visual impairments.
Purpose:
To provide population-based normative data for monocular visual acuity (VA) and interocular differences in VA (IOD) in Black and Hispanic children 30 to 72 months of age without visually significant refractive errors or ophthalmic abnormalities.
Methods:
In a population-based cohort of children in the Multi-Ethnic Pediatric Eye Disease Study, monocular HOTV VA measurements using the Amblyopia Treatment Study protocol were analyzed using continuous and dichotomous outcomes for VA and IOD, after excluding subjects with ophthalmic abnormalities or refractive error.
Results:
The analysis cohort consisted of 1722 Black and Hispanic children aged 30 to 72 months. Mean logMAR VA improved with age (p < 0.0001) and male gender (p = 0.0008). The proportion of children achieving VA 20/40 or better was associated with age (p < 0.0001), but not ethnicity or gender, and was 81, 94, 99, and virtually 100% in children aged 30 to 35, 36 to 47, 48 to 59, and 60 to 72 months of age, respectively. The most stringent VA threshold that excluded <5% of normal children was 20/63, 20/50, 20/32, and 20/32 for children aged 30 to 35, 36 to 47, 48 to 59, and 60 to 72 months, respectively. Children attending preschool or daycare achieved VA 20/32 more often than those not attending, after age adjustment (p = 0.01), as did children from higher-income families (p = 0.04). There was no association between mean absolute IOD and age (p = 0.45), ethnicity (p = 0.12), or gender (p = 0.19). The proportion of children with an IOD of 0 to 1 lines was higher in males than females (p = 0.02); it did not vary by age (p = 0.06) or ethnicity (p = 0.17). An IOD of 2 or more lines occurred in 6% of normal children.
Conclusions:
VA test performance in normal pre-school children improves with age. We propose new age-specific thresholds for defining abnormal monocular VA using HOTV optotypes in children between 2 and 5 years of age, for use in screening, clinical practice, and research.
