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Effect of age using Lea Symbols or HOTV for preschool vision screening
Insights
This study compared Lea Symbols and HOTV tests for preschool vision screening. While 3-year-olds performed better with Lea Symbols, neither test showed statistically significant differences in detecting vision problems in children.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Vision Science
Background:
- Early detection of vision impairments in children is crucial for preventing long-term visual deficits.
- Standardized vision screening tests are essential for identifying children needing further eye care.
- Lea Symbols and HOTV letter tests are commonly used for visual acuity assessment in young children.
Purpose of the Study:
- To compare the effectiveness of Lea Symbols and HOTV distance visual acuity tests for screening 3- to 5-year-old children.
- To evaluate the tests' ability to identify children requiring eye care due to amblyopia, strabismus, refractive error, or reduced visual acuity.
- To assess performance in linear, crowded formats at a 3-meter distance.
Main Methods:
- 1,142 Head Start children aged 3-5 years underwent comprehensive eye examinations.
- Masked examiners administered both Lea Symbols and HOTV tests randomly to each child.
- Optotype sizes were age-based, with specific charts used for 3- and 4-year-olds.
Main Results:
- Over 95% of children completed both vision screening tests without significant differences.
- In 3-year-olds, Lea Symbols showed higher sensitivity (61%) for detecting targeted conditions compared to HOTV (46%), but this was not statistically significant.
- No statistically significant differences in test sensitivity were found across any age groups, despite 3-year-olds achieving better acuity with Lea Symbols.
Conclusions:
- Both Lea Symbols and HOTV tests are feasible for vision screening in 3- to 5-year-old children.
- While preliminary results suggest potential differences in younger children, neither test demonstrated statistically significant superiority in detecting vision impairments.
- Further research may be needed to determine optimal screening tools for specific age subgroups.
Purpose:
To compare the effectiveness of the Lea Symbols and the HOTV distance visual acuity tests, presented monocularly in linear, crowded formats at 3 m, as vision screening tests to identify 3- to 5-year-old children in need of eye care.
Methods:
Subjects were 1,142 3- to 5-year-old Head Start children who completed a comprehensive eye examination, used to determine if the child had one or more targeted conditions: amblyopia, strabismus, significant refractive error, or unexplained reduced visual acuity. Each child was tested on both tests by masked examiners, with test order determined randomly. The optotype sizes administered were age-based according to the child's age at school entry on September 1. Children of age 3 were tested with 10/100, 10/32, 10/25, and 10/20 optotypes whereas those who were 4 were tested with 10/100, 10/25, 10/20, and 10/16 optotypes.
Results:
Most children (>95%) completed both tests, with no statistically significant differences. Pass/fail cut-offs were set to yield specificities as close as possible to 90%. The largest sensitivity differences observed were in the 3-year-old group (mean age, 45.3 months), where the sensitivity for detection of > or =1 targeted conditions was 61% for the Lea Symbols and was 46% for the HOTV letters (difference 15%, 95% confidence interval: -0.01 to 0.30) and the sensitivity for detection of group 1 conditions was 83% for the Lea Symbols and 57% for the HOTV letters (difference 26%, 95% confidence interval: -0.01 to 0.49). However, neither these differences nor any of the other age group sensitivity differences were statistically significant. For the 3-year-old children, the pass/fail criterion was one line larger for the HOTV letters than for the Lea Symbols.
Conclusions:
Most children completed both tests. Although the 3-year-old children achieved better acuity scores with the Lea Symbols test, there were no statistically significant differences in sensitivity between tests for any age group.
