The HOTV letter-matching vision test produced better uncorrected visual acuity results than the tumbling E test among younger children, with lower referral rates and better screening performance in preschool children, according to a cross-sectional observational study of 995 children aged 3 to 15 years. Differences between the tests diminished with age and were minimal by age 8 years.
The study, published in JAMA Ophthalmology, compared the 2 approaches because HOTV is recommended for pediatric vision screening, whereas tumbling E remains widely used internationally despite its higher cognitive demands for young children. Evidence directly comparing uncorrected visual acuity outcomes between the 2 tests across pediatric age groups has been limited.
The study was conducted in Shanghai, between September and December 2024 as part of a national multicenter study. Children aged 3 to 15 years underwent uncorrected visual acuity (UCVA) testing with both HOTV and tumbling E logMAR charts in randomized order, with a 30-minute rest period between tests to minimize fatigue.
Examiners were assigned to a single test and masked to results from the other test as well as the study hypothesis. Participants also underwent comprehensive eye examinations, including cycloplegic refraction.
Of 1,053 children assessed, 995 completed both UCVA tests. Because both tests produced poorer mean UCVA when administered second, consistent with a fatigue effect, investigators used only the first UCVA test for comparisons of mean values. After an additional exclusion intended to address a refractive imbalance among the oldest children, 980 participants were included in the mean UCVA analysis.
Overall, mean UCVA was 0.15 logMAR, approximately 20/25 Snellen, with HOTV compared with 0.20 logMAR, approximately 20/32, with tumbling E, a difference of 0.05 logMAR. The difference between the 2 tests decreased with age, reaching 1 line in children aged 3 to younger than 4 years and remaining more than 3 letters in those younger than 8 years before decreasing to 1 letter or less at age 8 years or older.
Referral and Screening Performance
For analyses of referral rates and screening performance, investigators excluded preschool children without cycloplegic refraction data, leaving 654 participants. Among 183 preschool children, 19% were identified with reduced UCVA based on HOTV results compared with 31% based on tumbling E results. Referral rates were similar between tests among lower primary school children and among upper primary and secondary school children.
Overall, 41% of the 654 children had a clinically relevant ocular condition, including refractive errors, suspected amblyopia, and 1 case of congenital cataract. Among preschool children, the true-positive rate was 0.68 with HOTV compared with 0.44 with tumbling E. The study also reported greater specificity with HOTV in this age group, at 93% vs 79%. Differences in screening performance diminished with age, with similar accuracy between tests among upper primary and secondary school children.
Twenty-one children, or 3%, were classified as having suspected amblyopia. Most children with suspected amblyopia were detected by either test; however, 2 preschool children would not have met the suspected amblyopia criteria based on the tumbling E test alone. The authors cautioned that these were suspected cases identified through screening rather than definitive amblyopia diagnoses and that the findings require confirmation in a larger sample of younger children with definitive amblyopia.
Refractive error screening was generally comparable between the tests. Among the 654 children, 29% had myopia, 3% had hyperopia, 18% had astigmatism, and 17% had anisometropia.
The HOTV test demonstrated slightly better performance than the tumbling E test in detecting myopia, with an area under the curve of 0.90 vs 0.86, and for astigmatism, at 0.71 vs 0.66. The reseachers noted that the absolute differences were small and that relatively few preschool and lower primary school children had refractive errors, which may have increased variability in these estimates.
Testability and Testing Time
Across all 1,053 participants, 95% could complete HOTV testing and 97% could complete tumbling E testing. Testability was 80% with HOTV and 83% with tumbling E among 69 preschool children who had no previous experience with vision testing.
Among 53 inexperienced preschool children who successfully completed both tests, HOTV required approximately 6.2 seconds longer for instruction and 7.9 seconds longer for testing, which amounted to about 14 additional seconds per child. The researchers estimated this would add 11.7 minutes if 50 young children were screened in 1 day.
Study Limitations
A primary limitation was that both tests were administered on the same day. Despite the 30-minute rest interval, performance was poorer on the second test, indicating a fatigue effect that limited the validity of direct within-child comparisons. The authors said administering the tests on separate days would provide a more valid intraindividual comparison.
They also noted that although the same HOTV and tumbling E charts were used, the staircase procedure and varied testing sequence minimized potential memorization bias.
The investigators concluded that the HOTV letter-matching test should be considered for universal vision screening in children younger than 8 years, particularly to reduce unnecessary referrals and improve screening efficiency in the context of increasing global emphasis on pediatric vision screening and detection of early-onset childhood myopia.
Disclosures: Ian G. Morgan, PhD, reported personal fees from Eyerising International outside the submitted work. Xiangui He, PhD, reported grants from the National Natural Science Foundation of China during the study. No other disclosures were reported. OM