Session Title: AMD II
Session Date/Time: Friday 12/09/2014 | 08:00-10:00
Paper Time: 09:20
Venue: Boulevard D
First Author: : S.YYu SOUTH KOREA
Co Author(s): : H. Kwak
To assess the feasibility and accuracy of a smartphone-based electronic method of visual acuity (VA) testing for remote monitoring and clinical research, and to evaluate its test-retest reliability and concordance with standard Early Treatment for Diabetic Retinopathy Study (ETDRS) testing.
The study was carried out in Kyung Hee University Hospital, Seoul, Korea.
Visual Acuity was measured with the smartphone-based electronic visual acuity (SEVA) testing algorithm (SightBookTM, DigiSight Technologies, Inc. Portola Valley, CA) at a test distance of 30 centimeters, twice, and both ETDRS distance chart and LEA numbers near vision chart, once, on one eye of each of 69 normal, 35 cataract, 55 diabetic, and 41 age-related macular degeneration (AMD) patients (n=200). Reliability and concordance were calculated using the Bland-Altman limits of agreement, the coefficient of repeatability (COR), and the intraclass correlation coefficient (ICC).
For the SEVA testing, test-retest reliability was high (ICCs= 0.977 of all patients, 0.980 of normal subjects, 0.957 of AMD, 0.966 of cataract, 0.970 of DR; 95% limits of agreement ± 0.20 logMAR). SEVA and near VA with LEA numbers chart were highly correlated (r2=0.671 of initial test in SEVA; r2=0.714 of repeated test in SEVA). There were no differences between SEVA and near VA with LEA numbers in all diseases and visual acuity groups. SEVA and distance VA by ETDRS were highly correlated (r2=0.757 of initial test in SEVA; r2=0.746 of repeated test in SEVA). There were no differences between VA with SEVA and distance VA with the ETDRS chart in all diseases and VA groups except the AMD group (p=0.003).
Smartphone-based electronic VA testing using the SightBookTM application has high test-retest reliability and good concordance with ETDRS distance visual acuity and standard near vision testing.