Sajeesh Kumar1, Max Bulsara, Kanagasingam Yogesan. 1. Centre of Excellence in e-Medicine, Lions Eye Institute, University of Western Australia, Nedlands WA, Australia. sajeesh@cyllene.uwa.edu.au
Abstract
PURPOSE: The aim of this study was to evaluate the visual acuity scores of a computer-based visual function testing (CVFT) system. The automated chart uses logMAR notation (logarithm of the minimum angle of resolution) and randomised tilting E as optotype. The test was conducted using a laptop computer. METHODS: This prospective, clinic-based, test validation study was based on a model of repeatability in two observations. The right eyes of a total of 104 participants were randomly tested with both CVFT and the manual, gold standard Early Treatment of Diabetic Retinopathy Study (ETDRS) chart. RESULTS: The mean difference between CVFT and ETDRS was -0.01+/-0.11 (SD) logMAR units. The Spearman Rank correlation coefficient (r) between the absolute difference and the average was 0.35. The average time for testing one eye was 54.7+/-11.89 seconds. The mean difference between two consecutive, repeated CVFT tests in the same eye was 0.02+/-0.07 logMAR units (paired t-test p=0.046). CONCLUSIONS: A novel, automated visual acuity testing application is reported. This automated system should be a useful tool for mass screening of visual impairment in rural and remote regions with its ease of use and shorter testing time.
RCT Entities:
PURPOSE: The aim of this study was to evaluate the visual acuity scores of a computer-based visual function testing (CVFT) system. The automated chart uses logMAR notation (logarithm of the minimum angle of resolution) and randomised tilting E as optotype. The test was conducted using a laptop computer. METHODS: This prospective, clinic-based, test validation study was based on a model of repeatability in two observations. The right eyes of a total of 104 participants were randomly tested with both CVFT and the manual, gold standard Early Treatment of Diabetic Retinopathy Study (ETDRS) chart. RESULTS: The mean difference between CVFT and ETDRS was -0.01+/-0.11 (SD) logMAR units. The Spearman Rank correlation coefficient (r) between the absolute difference and the average was 0.35. The average time for testing one eye was 54.7+/-11.89 seconds. The mean difference between two consecutive, repeated CVFT tests in the same eye was 0.02+/-0.07 logMAR units (paired t-test p=0.046). CONCLUSIONS: A novel, automated visual acuity testing application is reported. This automated system should be a useful tool for mass screening of visual impairment in rural and remote regions with its ease of use and shorter testing time.