Abstract
Background
Visual acuity (VA) represents a fundamental measure of visual function. The significant prevalence of underdiagnosed ocular disorders underscores the importance of effective VA assessment. This study evaluates the efficacy of a web-based VA assessment tool (“PocDoc”) versus conventional VA testing.
Methods
Prospective observational study including 353 participants recruited from various eye clinics in a tertiary referral centre. Age, diagnosis, and VA related information (i.e. VA measurements from PocDoc and conventional VA test [Snellen chart], test type, etc) were collected. Spearman’s rank correlation, Intraclass Correlation, and Bland-Altman plot compared outcomes of both tests. One-way ANOVA and paired-T test were used to compare means.
Results
Most patients were males (59.2%) with a mean age of 52.2 ± 20.6 years. PocDoc had moderate positive correlation to conventional testing (rho = 0.50, p < 0.001). PocDoc led to higher logMAR scores compared to conventional testing (mean logMAR 0.19 and 0.13 respectively, p < 0.01). Moreover, PocDoc demonstrated a sensitivity of 82.8% and specificity of 79% for detecting visual impairment. The discrepancy between PocDoc and conventional VA testing increased with higher logMAR values, indicating greater inconsistency between the tests for patients with poorer VA. Age, test type, and disease type contributed to this variability.
Conclusions
The concordance between PocDoc and conventional testing for VA measurement across various ages and conditions makes it a suitable screening tool. Future technological inventions should consider age, test type, and disease type as critical factors related to the level of agreement and correlation between digital and conventional VA testing methods.
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Data availability
Data supporting the findings of this study are available from the corresponding author upon reasonable request.
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Acknowledgements
We thank Dr Benjamin Chang Chong Ming for assisting in patient recruitment.
Funding
This work is supported by a research grant from the Ng Teng Fong Healthcare Innovation Programme (NTF HIP). Grant number: NTF_DEC2019_I_C1_C_02. The sponsor or funding organization had no role in the design or conduct of this research.
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JB was responsible for patient recruitment, data collection, project management, and drafting the manuscript. JSG contributed to data preprocessing, drafting, and editing the manuscript. WRC performed data analysis, edited the manuscript, and created the figures. MP was involved in patient recruitment, data collection, and manuscript editing. BL supervised data analysis and contributed to manuscript editing. RR recruited patients and edited the manuscript. BA participated in patient recruitment and manuscript editing. RA supervised the project and edited the manuscript.
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No conflicting relationship exists for any author. No competing financial interests exist. The PocDoc app was submitted for an invention disclosure funded by NTF- HIP_DEC2019_C1_C_02.
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Boon, J., Goh, J.S., Rojas-Carabali, W. et al. Web-based vs. conventional: a comprehensive analysis of visual acuity assessment using the PocDoc tool in a tertiary eye care centre. Eye 38, 3554–3561 (2024). https://doi.org/10.1038/s41433-024-03362-0
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DOI: https://doi.org/10.1038/s41433-024-03362-0
