Printed cards for measuring low-vision reading speed

Abstract

There is a growing consensus that clinical evaluation of the real-world consequences of eye disease requires new performance-based tests. This is because Snellen acuity and other common clinical tests are often poor predictors of everyday function. Ahn and Legge [(1995) Vision Research, 35, 1931-1938] validated a computerized test of reading speed by showing that it provides an accurate prediction of low-vision reading performance with magnifiers. Here, we describe development of a printed-card version of the test suitable for clinical use. This printed-card test retains key design features of the validated computerized test, including the same set of sentences and display format. Data from 23 low-vision subjects showed that a very simple testing procedure using printed cards and a stop watch could be used effectively to estimate reading speed. Reading speed based on a single card was quite accurate (SD equal to about 18% of the mean) and showed no practice effects from one card to the next. Reading speeds obtained with printed cards correlated highly (r = 0.887) with those from computerized testing. We conclude that a simple test, using printed cards, can be used to obtain useful estimates of low-vision reading speed.