A computerized method of viual acuity teting: Adaptation of the early treatment of diabetic retinopathy tudy teting protocol

Abtract Purpoe To develop a computerized method of viual acuity teting for clinical reearch a an alternative to the tandard Early Treatment for Diabetic Retinopathy tudy (ETDR) teting protocol, and to evaluate it tet-retet reliability and concordance with tandard ETDR teting. Deign Tet-retet reliability tudy. Method Multicenter etting of a tudy population of 265 patient at three clinical ite. Viual acuity wa meaured with both the electronic viual acuity teting algorithm (E-ETDR) and tandard ETDR protocol (-ETDR) twice on one eye of each patient. E-ETDR teting wa conducted uing the electronic viual acuity teter (EVA), which utilize a programmed Palm (Palm, Inc, anta Clara, California, UA) hand-held device communicating with a peronal computer and 17-inch monitor at a tet ditance of 3 meter. Reult For the E-ETDR protocol, tet-retet reliability wa high (r = 0.99; with 89% and 98% of retet within 0.1 logMAR and 0.2 logMAR of initial tet, repectively) and comparable with that of -ETDR teting (r = 0.99; with 87% and 98% of retet within 0.1 logMAR and 0.2 logMAR of initial tet, repectively). The E-ETDR and -ETDR core were highly correlated (r = 0.96 for initial tet and R = 0.97 for repeat tet). Baed on etimate of 95% confidence interval, a change in viual acuity of 0.2 logMAR (10 letter) from a baeline level i unlikely to be related to meaurement variability uing either the E-ETDR or the -ETDR viual acuity teting protocol. Concluion The E-ETDR protocol ha high tet-retet reliability and good concordance with -ETDR teting. The computerized method ha advantage over the -ETDR teting in electronically capturing the data for each teted letter, requiring only a ingle ditance for teting from 20/12 to 20/800, potentially reducing teting time, and potentially decreaing technician-related bia.