Abstract
Purpose :
The early detection of childhood visual impairment, mostly caused by preventable and/or treatable disorders, is one of the goals of Vision 2020 WHO program. In this context, school screening is an important tool to achieve it. We performed an observational clinical study to evaluate the effectiveness of teachers visual acuity test (VAT) through the agreement of the visual acuity (VA) information obtained from teachers and ophthalmologists.
Methods :
The VAT was performed by ophthalmologists and teachers with a tumble “E” ETDRS chart. All teachers from Sete Barras, Sao Paulo, Brazil, have received a general orientation about ocular health but one group have received an extra formal theoretical and practical course on visual acuity (trained teachers) while the other have not (untrained teachers). Selected children from 3 to 14 years old had two VA measurements in the same occasion: one by the teacher (either trained or untrained) and one by an ophthalmologist. The difference in the number of correctly read optotipes in the better eye measured by teachers and ophthalmologists was calculated and compared through multiple linear regression adjusted for children’s year in school and VAT order. Bland-Altman graphs were used for qualitative analysis and the intra-class correlation (ICC) was calculated.
Results :
A total of 162 children (mean age 9.22±2.84 years old) were recruited for the study. All of them were evaluated by an ophthalmologist, with 87 (53.7%) also evaluated by a trained teacher and 75 (46.3%) by an untrained teacher. The mean difference in the number of optotipes from trained teachers and ophthalmologists was -0.09±5.71 while the mean difference from untrained teachers and ophthalmologists was -1.01 ±9.09. The observed differences, however, were not statistically significant (p=0.539). The qualitative Bland Altman analysis show a better agreement in cases of good visual acuity when compared to poor visual acuity and the ICC shows higher agreement of ophthalmologist measurement with trained teachers (ICC=0.8058) than untrained teachers (ICC=0.6252).
Conclusions :
Teacher′s VAT can be used as a visual screening test in school visual programs but adequate training should be provided for teachers prior the tests, focusing in cases of low visual acuity.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.