Clinical validation of a cross-platform digital visual acuity measurement system

Abstract

ABSTRACT Objective: To validate visual acuity measurements using a cross-platform system in an ophthalmological setting. Methods: Visual acuity was assessed at a distance of 5m using two different modalities: printed and digital optotypes. The devices included Android, LG WebOS and Samsung Tizen smart TVs. Optotypes were presented in the logMAR scale. Two modalities, a single row and a block of symbols, presented Sloan letters and Tumbling E symbols. Results: Visual acuity measurements of 190 participants aged 12 to 60 years demonstrated good-to-strong test-retest correlation (Intraclass Correlation Coefficient >0.75) and minimal bias (-0.03 to 0.02 logMAR). Limits of agreement were comparable to other studies (0.13 to 0.26 logMAR), with the smallest values for Tumbling E row presentation in all devices and the highest value for Sloan chart in LG device. Analysis of variance revealed no statistical differences in visual acuity across devices. Sloan letters showed superior visual acuity compared to Tumbling E (p<0.001); however, this difference corresponded to only 2 letters of visual acuity. Conclusion: The digital cross-platform evaluated serves as a versatile substitute for traditional visual acuity assessments in individuals aged 12 years and older. Further research is necessary for patients with visual acuity worse than 0.5 logMAR and to conduct vision screenings in young children.

Keywords

• Visual acuity
• Refraction, ocular
• Vision tests
• Vision screening
• Psychophysics