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Should tumbling E go out of date in amblyopia screening? Evidence from a population-based sample normative in
Sandra Guimaraes1,2,3, Tiago Fernandes1, Patrício Costa2,3,4
1Department of Ophthalmology, Hospital de Braga, Braga, Portugal.
Insights
This study establishes a visual acuity (VA) standard for 3-4 year olds using the tumbling E optotype, showing high testability and reliable results. The tumbling E optotype is feasible for assessing VA in young children.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Public Health
Background:
- Accurate visual acuity (VA) assessment in young children is crucial for early detection of vision impairments.
- Existing optotypes may have limitations in testability and reliability for preschool-aged children.
Purpose of the Study:
- To establish a normative standard for visual acuity using the tumbling E optotype in children aged 3-4 years.
- To evaluate the feasibility and testability of the tumbling E optotype for VA assessment in this age group.
Main Methods:
- A cross-sectional study involving 1756 children aged 3-4 years.
- Comprehensive non-invasive eye examinations including uncorrected monocular VA with crowded tumbling E.
- Evaluation of testability rates and VA across different age subgroups, genders, school types, and testing orders.
Main Results:
- Overall testability rate was 95% (92% for 3-year-olds, 98% for 4-year-olds).
- Mean VA was 0.14 logMAR (first-day) and 0.13 logMAR (best over 2 days), showing correlation with HOTV-ATS standards.
- Low false-positive referral rate (1.3%), with minimal overestimation compared to HOTV-ATS.
Conclusions:
- The tumbling E optotype provides a feasible and reliable method for VA assessment in 3-4 year old children.
- Testability rates with the tumbling E optotype are higher than reported for other optotypes, particularly in 3-year-olds.
- This study provides the first normative data for European Caucasian children using the single crowded tumbling E optotype.
Aims:
To determine a normative of tumbling E optotype and its feasibility for visual acuity (VA) assessment in children aged 3-4 years.
Methods:
A cross-sectional study of 1756 children who were invited to participate in a comprehensive non-invasive eye exam. Uncorrected monocular VA with crowded tumbling E with a comprehensive ophthalmological examination were assessed. Testability rates of the whole population and VA of the healthy children for different age subgroups, gender, school type and the order of testing in which the ophthalmological examination was performed were evaluated.
Results:
The overall testability rate was 95% (92% and 98% for children aged 3 and 4 years, respectively). The mean VA of the first-day assessment (first-VA) and best-VA over 2 days' assessments was 0.14 logMAR (95% CI 0.14 to 0.15) (decimal=0.72, 95% CI 0.71 to 0.73) and 0.13 logMAR (95% CI 0.13 to 0.14) (decimal=0.74, 95% CI 0.73 to 0.74). Analysis with age showed differences between groups in first-VA (F(3,1146)=10.0; p<0.001; η2=0.026) and best-VA (F(3,1155)=8.8; p<0.001; η2=0.022). Our normative was very highly correlated with previous reported HOTV-Amblyopia-Treatment-Study (HOTV-ATS) (first-VA, r=0.97; best-VA, r=0.99), with 0.8 to 0.7 lines consistent overestimation for HOTV-ATS as described in literature. Overall false-positive referral was 1.3%, being specially low regarding anisometropias of ≥2 logMAR lines (0.17%). Interocular difference ≥1 line VA logMAR was not associated with age (p=0.195).
Conclusions:
This is the first normative for European Caucasian children with single crowded tumbling E in healthy eyes and the largest study comparing 3 and 4 years old testability. Testability rates are higher than found in literature with other optotypes, especially in children aged 3 years, where we found 5%-11% better testability rates.
