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Updated: Oct 16, 2025
Author Spotlight: An Automated Method for Assessing Visual Acuity in Infants and Toddlers Using an Eye-Tracking System
Published on: March 17, 2023
Novel web application for self-assessment of distance visual acuity to support remote consultation: a real-world
Louise Allen1, Arun James Thirunavukarasu2, Simon Podgorski2
1Department of Ophthalmology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK.
Insights
A new digital tool, DigiVis, accurately measures distance visual acuity (VA) in children at home, comparable to clinical tests. This technology supports remote consultations, reducing school absences and optimizing clinic capacity.
Area of Science:
- Ophthalmology
- Digital Health
- Pediatric Care
Background:
- Accurate distance visual acuity (VA) assessment is crucial for remote ophthalmology consultations.
- Current home-based VA testing methods are often unreliable, limiting telemedicine's effectiveness.
- A novel web application, DigiVis, offers automated VA self-assessment via digital devices.
Purpose of the Study:
- To evaluate the accuracy and reliability of the DigiVis application for distance VA self-assessment in children.
- To compare DigiVis performance against standard clinical VA assessments conducted by healthcare professionals.
- To gather user feedback on the acceptability and usability of the DigiVis tool.
Main Methods:
- Recruited children aged 4-10 years from a pediatric ophthalmology service.
- Excluded participants with VA worse than +0.8 logMAR or cognitive impairment.
- Employed Bland-Altman statistics for accuracy and repeatability analysis; collected user feedback via questionnaire.
Main Results:
- Tested 89 children; DigiVis showed a mean bias of 0.023 logMAR (LOA ±0.195, ICC 0.816) compared to clinical assessment.
- Test-retest reliability was high (mean bias 0.010, LOA ±0.179, ICC 0.815).
- 96% of children and 99% of parents rated the test as good or excellent.
Conclusions:
- Digital self-testing with DigiVis provides accurate distance VA assessments in children, comparable to clinical evaluations.
- The tool demonstrated high user acceptance among both children and parents.
- DigiVis, used with remote supervision, can facilitate online pediatric eye clinic appointments, reducing patient burden and enhancing clinical efficiency.
Objective:
The difficulty in accurately assessing distance visual acuity (VA) at home limits the usefulness of remote consultation in ophthalmology. A novel web application, DigiVis, enables automated VA self-assessment using standard digital devices. This study aims to compare its accuracy and reliability in children with clinical assessment by a healthcare professional.
Methods And Analysis:
Children aged 4-10 years were recruited from a paediatric ophthalmology service. Those with VA worse than +0.8 logMAR (Logarithm of the Minimum Angle of Resolution) or with cognitive impairment were excluded. Bland-Altman statistics were used to analyse both the accuracy and repeatability of VA self-testing. User feedback was collected by questionnaire.
Results:
The left eyes of 89 children (median 7 years) were tested. VA self-testing showed a mean bias of 0.023 logMAR, with a limit of agreement (LOA) of ±0.195 logMAR and an intraclass correlation coefficient (ICC) of 0.816. A second test was possible in 80 (90%) children. Test-retest comparison showed a mean bias of 0.010, with an LOA of ±0.179 logMAR, an ICC of 0.815 and a repeatability coefficient of 0.012. 96% of children rated the test as good or excellent, as did 99% of their parents.
Conclusion:
Digital self-testing gave comparable distance VA assessments with clinical testing in children and was well accepted. Since DigiVis self-testing can be performed under direct supervision using medical video consultation software, it may be a useful tool to enable a proportion of paediatric eye clinic attendances to be moved online, reducing time off school and releasing face-to-face clinical capacity for those who need it.
