Comparison of Visual Acuity Results in Preschool Children with Lea Symbols and Bailey-Lovie E Chart

Abstract

Purpose:

To compare visual acuity with two visual acuity charts in preschool children.

Materials and Methods:

Visual acuity measurement with Lea symbols and Bailey-Lovie tumbling E chart was performed on children between 3 and 6 years of age. Visual acuity data from the two charts were analyzed with Bland-Altman plot to determine the limits of agreement. The Wilcoxon signed test was performed in children aged 3-4 years and in children aged 5-6 years separately to evaluate the influence of age. The inter-eye difference between the two charts were further analyzed with the paired t-test. A p value > 0.05 was considered statistically significant.

Results:

A total of 47 children were enrolled for the study. The average logarithm of the Minimum Angle of Resolution (LogMAR) monocular visual acuity with Lea symbols (0.17 ± 0.13) was better than the Bailey-Lovie tumbling E chart (0.22 ± 0.14). The mean difference between Bailey-Lovie tumbling E chart and Lea symbol chart was 0.05 ± 0.12 in logMAR units. A second analysis eliminating outliers showed the same result but lower differences ( n = 43, 0.05 ± 0.05 logMAR units). Visual acuity results between the two charts in children aged 3-4 years showed a significant difference ( p = 0.000), but not for children aged 5-6 years ( p = 0.059). Inter-eye differences between the two charts was not statistically significant ( p = 0.77).

Conclusion:

Bailey-Lovie tumbling E chart is comparable to the Lea symbols chart in pre-school children. But preference should be given to Lea symbols for children aged 3-4 years as the symbols are more familiar than a directional test for this age group.