Abstract
Purpose :
To evaluate the relationship between maximum reading speed (MRS) scores derived from 2 widely used reading speed tests in order to assess correlation and interchangeability.
Methods :
Patients from English-speaking countries (United States, United Kingdom, Australia; N = 81), with bilateral geographic atrophy (GA) and no choroidal neovascularization, who were enrolled in a natural history study, Proxima A (NCT02479386), were asked to complete 2 different reading speed tests at baseline and month 12: the Minnesota Low-Vision Reading Test (MNRead) and Radner Reading Chart. The results of the reading tests were analyzed for correlation between results: MRS score in words per minute (wpm; monocular and binocular) and change from baseline in MRS (monocular and binocular).
Results :
Patients had a mean (SD) age of 81.3 (6.9) years, 63% were female, and 95% were white. Functional and anatomic characterization of the study eye at baseline was characterized as follows. Mean (SD) best-corrected visual acuity, low-luminance visual acuity, and low-luminance deficit were 66.3 (9.1), 33.3 (18.0), and 33.0 (17.0) letters, respectively. Mean (SD) GA area was 7.67 (3.84) mm2; 79.2% of patients had multifocal lesions, and 48.1% of patients had subfoveal lesions. Mean (SD) distance to central fovea for non-subfoveal GA was 240.3 (195.6) µm. Results from the 2 reading speed tests at baseline and follow up were compared as follows. The monocular MRS scores derived from the MNRead and Radner Reading Chart were highly correlated at baseline (n = 78, r=0.88) and month 12 (n = 48, r = 0.76; Figures 1 and 2). Binocular MRS scores were also highly correlated between the 2 assessments at baseline (n = 80, r = 0.87) and month 12 (n = 50, r = 0.89). Change from baseline on the 2 reading speed charts were moderately correlated for binocular MRS (n = 50, r = 0.57), and monocular MRS (n = 48, r = 0.43).
Conclusions :
The results demonstrate a strong correlation in MRS data obtained from the MNRead and Radner Reading Chart, both for monocular and binocular tests, at baseline and month 12. Due to early study termination, only ~60% of patients had month 12 assessments. More research will be needed to better understand the relationship between changes in the 2 reading speed tests over time.
This is a 2020 ARVO Annual Meeting abstract.