Concordance between the Snellen Numbers Test and Lea Numbers Test in Children between Four and Seven Years of Age

Abstract

The assessment of visual acuity in school children is done using eye charts. The most used inclinical practice are Snellen and Bailey Lovie. The way they evaluate vision in children doesnot differ much from the way it is done with adults. However, when selecting the test, cognitivedevelopment must be taken into account. Objective: To determine the correlation between theSnellen numbers test and Lea numbers test in children between four and seven years of age inBogota. Materials and methods: The sample was chosen for convenience. We evaluated 169 visuallyhealthy children (331 eyes), aged between four and seven years, in the schools of the Institutode Bienestar Familiar, Bogota Optometry Clinic schools, and University of La Salle, between Mayand August 2011. Visual acuity (av) was assessed with a Snellen numbers chart and Lea numberschart with a Bailley Lovie type design. A Spearman test was used to determine the correlationbetween the two charts. Results: Results of the Spearman correlation test found a correlation of0.462 between both tests - moderate but statistically significant. With the Mann-Whitney test asignificant difference between measurements with both av tests was found. Conclusions: Snellenand Lea tests are different and, therefore, not interchangeable.