Does A Line Guide Improve Reading Performance With Stand Magnifiers?

Background: When reading with a stand magnifier (SM), navigation along each line of text and retracing back to the correct position at the beginning of the next line has been suggested as a major difficulty for people with low vision. In this study, we evaluated the immediate impact of using a simple and inexpensive line guide on navigation performance.--- Methods: Twenty-nine participants with age-related macular degeneration read short passages of text using their habitual SM with and without a temporary line guide attached. Magnifier movements were recorded using a 3 SPACE Isotrak system. Reading time, magnifier movement strategies, navigation times and navigation errors were determined. A short questionnaire was used to quantify participants’ perceived difficulties with page navigation and their preference for reading with or without the line guide.--- Results: For some participants, the line guide improved the control of the vertical positioning of the SM when reading along a line (p=0.01), but it increased the number of corrective vertical movements at the end of the retrace (p=0.001). There was a small but significant decrease (about 6wpm) in reading speed and increase in navigation times (p