Validation of a Standardized Home Visual Acuity Test for Teleophthalmology.

Area of Science:

• Ophthalmology
• Telemedicine
• Medical Technology

Background:

• Teleophthalmology is rapidly expanding but lacks validated remote visual acuity (VA) measurement methods.
• Accurate remote VA assessment is crucial for expanding access to eye care and managing conditions like diabetic retinopathy.

Purpose of the Study:

• To investigate the validity of a self-administered Early Treatment Diabetic Retinopathy Study (ETDRS) home visual acuity (VA) test.
• To determine if a home-based ETDRS chart is equivalent to a standard in-clinic technician-administered VA test.

Main Methods:

• A prospective cohort study involving 209 eyes from 108 patients.
• Patients completed a self-administered ETDRS VA test at home using a printout chart before an in-person clinic visit.
• VA was measured both at home and in-clinic using standard ETDRS charts; bioequivalence testing was performed.

Main Results:

• The mean adjusted VA letter score difference between home and clinic tests was 4.1 letters (90% CI, 3.2-4.9), within the 7-letter equivalence margin.
• Average unadjusted VA scores were 3.9 letters higher in the clinic compared to home (90% CI, 3.1-4.7).
• Ninety-eight percent of patients found the home test easy to perform.

Conclusions:

• A self-administered ETDRS VA test at home is equivalent to a standard in-clinic technician-administered test.
• This validated home-based method supports the expansion of teleophthalmology services.
• The ease of use reported by patients suggests high potential for adoption.