Abstract
Purpose :
Difficulty in reading is one of the most common problems faced by visually impaired people (VIP). Specifically designed optical aids or electronic vision enhancement systems (EVES) may be recommended to help with this task. There are now free apps which turn a smartphone into a portable EVES. This study investigated the reading speed achievable with the use of these apps in smartphones, compared to portable devices specifically designed for VIPs.
Methods :
Reading performance was measured with two groups of normally sighted individuals (under age 35 and over age 60) with two different levels of simulated visual impairment (VI) (mild and moderate). The reading test used was designed specifically for the study, and used 150 familiar, unrelated, words in Times Roman 8 point font. The words were arranged across 8 lines, to allowed testing of page navigation ability.
The portable EVES device was used both hand-held and on a stand, and compared with two different free apps tested with a smart phone, one of which used image stabilisation. The devices were used with 3x magnification with the mild VI, and 10x magnification with the moderate VI, to ensure adequate acuity reserve. Performance was also measured with several different colour displays available on the EVES (real colour; black-on-white; white-on-black; blue-on-yellow; yellow-on-blue).
Results :
Reading speed was slower in moderate than mild impairment for both age groups. The reading speed was slower in the older than the younger group using all four methods, and this was particularly the case for reading with the apps (p≤0.001). Both groups read fastest with the stand-mounted EVES with mild impairment; but for the younger group the hand-held EVES was fastest with moderate impairment. When comparing the different colour display modes, black-on-white supported the highest reading speed for both levels of impairment for both groups. Word errors were minimal in both groups, but page navigation errors (missed and repeated lines) occurred more commonly in the older group when using the apps.
Conclusions :
For naïve users with simulated impairment, a higher reading speed can be obtained by using an EVES compared to apps on a smartphone: some older users may also find this option better to avoid line-finding errors. Additional training may be necessary to ensure VIPs can use the apps optimally.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.