Prompted by the current COVID-19 pandemic, the American Academy of Ophthalmology has recommended the use of telemedicine to continue ophthalmic care while maintaining patient and provider social distancing. As part of remote examinations, patients may be expected to perform home eye testing for visual acuity and the use of various home visual acuity charts have been proposed to provide clinicians with this vital data. However, the use of home visual acuity exams has not been validated in our patient population. This project aims to determine the efficacy and validity of measuring visual acuity at home with a printed-out ETDRS chart.
Project Title Validity of Home Visual Acuity Measurements with an ETDRS Chart
Project Summary Prompted by the current COVID-19 pandemic, the American Academy of
Ophthalmology has recommended the use of telemedicine to continue ophthalmic care while
maintaining patient and provider social distancing. As part of remote examinations, patients
may be expected to perform home eye testing for visual acuity and the use of various home
visual acuity charts have been proposed to provide clinicians with this vital data. However,
the use of home visual acuity exams has not been validated in our patient population. This
project aims to determine the efficacy and validity of measuring visual acuity at home with a
printed-out ETDRS chart.
Project Description Rationale: Many ophthalmology visits are being conducted remotely via
telehealth. The use of home ETDRS charts is being proposed for patients to report their
visual acuity. However, the efficacy and validity of this method in our population should be
determined.
Objective: Determine the efficacy and validity of measuring visual acuity at home with a
printed-out ETDRS chart in the population served by Vanderbilt Eye Institute. Our hypothesis
is that measuring visual acuity at home with a printed-out ETDRS is non-inferior to visual
acuity measurements by a trained technician in the clinic.
Methodology: The study population will include patients scheduled for in-person visits for
various subspecialties (Glaucoma, Retina/Uveitis, Pediatrics and Cornea) at Vanderbilt Eye
Institute's (VEI) Nashville campus during the period of 4/27/20-5/27/20. Patients will be
excluded if they have a last best corrected visual acuity worse than 20/200, have not
activated a My Health at Vanderbilt (MHAV) account, or do not speak English. Patients will
also need to be between the ages of 18-90 to Approximately one week prior to their
appointments, patients will be called to obtain e-consent and provide detailed instructions
for measuring best corrected visual acuity at home with the ETDRS chart that is calibrated
for 5 feet. Instructions will also be sent via MHAV along with the ETDRS chart and the
consent form. Data collected will include age, sex, and primary ophthalmological diagnosis as
well as last measured Snellen visual acuity (+/-3months). The department, provider, and date
of the in-person appointment will also be collected. Patients will be instructed to complete
a home visual acuity check two-four days prior to appointment and send a message through MHAV
with the results. Participants will record the smallest full line ( 5 letters) in each eye
that they can read. If a message is not received two days prior to the appointment, a
research assistant will call the patient back to reconfirm the plan. At the in-person visit,
patients will begin their encounter with an ETDRS assessment at VEI, using the ETDRS chart at
20 feet. Again, the full line of 5 letters read will be used for analysis. Patients will
receive a survey to be completed in clinic with a 5-point Likert scale to rate the ease of
home visual acuity as well as a short response question about barriers to assessment.
Data Management and Analysis: Data will be collected from the electronic health record (EHR)
and kept in a password-protected deidentified Excel document. Visual acuities will be
converted to logMAR for analysis.
Ethical Considerations: There are no ethical considerations to report.
Barriers to Home Visual acuity testing
- Poor/no access to the technical requirements - computer, printer, internet
- Do not feel confident of being able to test vision accurately at home
- Attempted to test vision at home but was unable to follow instructions completely
- Do not want to try it at home, medical procedures should be done in a clinic
- Vision too poor to perform these tasks
The Home visual acuity test was easy to set up and perform
1. Strongly disagree
2. Disagree
3. Neither agree nor disagree
4. Agree
5. Strongly agree
Other: Non invasive visual acuity testing
This will be visual acuity at home and visual acuity in clinic both using an ETDRS chart.
Inclusion Criteria:
- The study population will include patients scheduled for in-person visits for various
subspecialties (Glaucoma, Retina/Uveitis, pediatrics and Cornea) at Vanderbilt Eye
Institute's (VEI) Nashville campus during the period of 4/27/20-5/8/20.
Exclusion Criteria:
- Patients will be excluded if they have a last best corrected visual acuity worse than
20/200.
- If they have not activated a My Health at Vanderbilt (MHAV) account
- If they do not speak English.
Vanderbilt Eye Institute
Nashville, Tennessee, United States