For preschool vision screening, the choice of chart may matter more than it appears. A large cross-sectional study published in JAMA Ophthalmology found that the HOTV letter-matching test produced better uncorrected visual acuity (UCVA) results than the widely used tumbling E test in younger children, with important implications for screening accuracy and referral burden.
The researchers studied 995 children aged three to 15 years in Shanghai. Each child completed both HOTV and tumbling E logMAR testing in randomized order, separated by a 30-minute rest period, alongside cycloplegic refraction and comprehensive ophthalmic examination.
Overall, mean UCVA was better with HOTV than with tumbling E: 0.15 logMAR (approximately 20/25) versus 0.20 logMAR (approximately 20/32), respectively. Crucially, the difference was strongly age-dependent. Among children aged three to four, the gap reached one full logMAR line. Differences remained greater than three letters in children younger than eight, but fell to one letter or less thereafter.
The authors argue that this age effect is unlikely to reflect an inherent optical advantage of HOTV. Rather, younger children may struggle with the directional and visuospatial demands of identifying the orientation of the tumbling E, abilities that continue to mature with age.
That difference translated directly into referral rates. Among 183 preschool children, 18.6% were classified as having reduced UCVA with HOTV compared with 31.2% using tumbling E. HOTV also produced a higher true-positive rate in this age group – 0.68 versus 0.44 – and better specificity. In older children, performance between the two tests became increasingly similar.
Importantly, the apparent screening advantage did not come at the cost of feasibility. Overall testability was 95.1% for HOTV and 96.5% for tumbling E, a nonsignificant difference. Among young preschoolers with no previous experience of vision testing, testability was also comparable. HOTV required only modestly longer instruction and testing time.
Both tests nevertheless missed some clinically relevant ocular conditions, particularly hyperopia and borderline refractive errors, which the authors noted was in line with other previous studies. The authors also acknowledge a key limitation: both tests were administered on the same day, introducing a measurable fatigue effect despite the 30-minute rest interval.
The findings nonetheless support HOTV as the preferred screening tool for children younger than eight. With expanding preschool vision programs and growing interest in early myopia detection, the authors suggest that using HOTV could improve screening efficiency while sparing families and eye care services from avoidable referrals, noting that this is especially true “in the context of growing global emphasis on pediatric vision screening and early detection of myopia.”
