Accuracy of Mobile-Based Vision Chart in Clinical Practice during the COVID-19 pandemic

ABSTRACT

Purpose

The accuracy of mobile-based visual acuity testing in clinical practice is debatable. This study aimed to analyze the accuracy of mobile-based distant vision chart in comparison to the standard chart projector.

Methods

In this cross-sectional study, monocular distant best-corrected visual acuity (BCVA) in 571 eyes of 288 subjects was measured twice, using the Tumbling E vision chart by standard chart projector and repeated using mobile-based vision chart application with screen mirroring on a 22-inch monitor. The decimal results of BCVA were compared to analyze the accuracy of the mobile-based chart in comparison to the standard vision chart projector.

Results

The mean age of the studied patients was 29 ± 14 years. The most frequent refractive error was hyperopia (35.4%), followed by emmetropia (26.7%), myopia (22.9%), and astigmatism (14.9%). The mean BCVA in decimal form was 0.9 ± 0.2 and 0.91 ± 0.26 by the standard and mobile-based charts, respectively. An excellent agreement was reported between both tests as the intraclass correlation coefficient (ICC) was 0.976, with a confidence interval (CI) of 0.965–0.982. Bland–Altman analysis revealed that most visual acuity differences between both methods lie on the equality line or within the allowed difference zone.

Conclusions

The mobile-based vision chart is an economical, accessible, and accurate way for distant vision assessment, and its results are comparable to the standard chart projector in clinical practice.

KEYWORDS:

• Economic
• mobile vision chart
• teleophthalmology
• visual acuity

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

Patients’ data used to support the results of this study are available upon request to the corresponding author.

Additional information

Funding

The author(s) received no financial support for this research.