Purpose: Two preliterate acuity charts, the Lea Symbol chart and the HOTV chart, were compared prospectively in an established preschool vision screening program. The charts were compared by measuring time required to test, reliability coefficients, and the percentage of children testable with each chart.
Methods and materials: Seven hundred and seventy-seven 3- to 5-year-old children were randomized to four screening sequences that determined the order of chart use. Each child was screened on two occasions within 6 weeks. Testing was performed at 10 feet, and optotypes were not isolated for testing.
Results: Mean test time was significantly less for older children, but was not related to the chart used. Reliability coefficients were similar for the Lea Symbols and the HOTV charts. The percentage of children testable by each chart improved with increased age of the child. More 3 year olds were testable with the Lea Symbols chart compared to the HOTV chart (92% versus 85%, P = .05).
Conclusions: Vision screening with either chart was more rapid and more frequently achieved with 4- and 5-year-old children compared with the 3 year olds. For the population as a whole, each chart gave similar results. Among the 3 year olds, however, testability rates were better for the Lea Symbols chart. The Lea Symbols chart is an acceptable option for preschool vision screening, and may be more efficacious than the HOTV chart for screening 3-year-old children.