Researchers in China have validated a self-administered version of the ETDRS visual acuity (VA) chart to monitor patients with retinal disease. 

Published in the British Journal of Ophthalmology, the prospective study included 256 participants with diabetic retinopathy (DR) or age-related macular degeneration (AMD), divided into a testing group (n=100) and a validation group (n=156). All participants underwent monocular distance best-corrected VA (BCVA) tests in the study eye using the standard ETDRS (S-ETDRS) charts in clinic and the home ETDRS (H-ETDRS) device in a simulated home setting. Participants in the validation group repeated both methods, while those in the testing cohort repeated both methods using a Bangerter filter to simulate reduced VA. 

Results showed close agreement between standard and home testing, with the mean difference between S-ETDRS and H-ETDRS scores being −1.38 letters in the validation group, said researchers. Test-retest reliability was consistent for both methods, though variability was greater with H-ETDRS. For participants in the testing group who showed BCVA decline of one line or more using the Bangerter filter, 96.7% were able to detect VA changes using H-ETDRS, the study found. 

H-ETDRS offers a valid method for monitoring VA in retinal disease, concluded authors.