Introduction: The ability to measure a patient's visual acuity at home (HVA) is by far the most desired remote telemedicine capability sought by ophthalmologists. Methods: A systematic literature review was done using Pubmed to search for publications from 2010 to 2022 in English reporting on 10 studies that compared a patient's HVA to the clinic visual acuity (CVA). Results: Approaches to measuring HVA included using a phone-based application, a physical chart, a computer, and a website. The most accurate of these was the use of personal computers (COMPlog, Macustat, Web based test) at home with a bias of 1 letter. The most accessible and reliable was the use of a printable visual acuity chart, available in the public domain, which had adifference between HVA and CVA of 1 to 3.5 letters. Phone apps (Verana Vision) and stand-alone websites (Farsight.com) both had a greater mean difference of about 6 letters, respectively,with a moderate correlation coefficient. Discussion: Overall, all three methodologies demonstrated a good negative predictive value demonstrating their potential use as an effective screening tool to flag drastic vision decline between clinic visits.
Keywords: ETDRS chart; home vision; home visual acuity; phone applications; telemedicine.