The aim of these studies has been to investigate the effect of ageing and visual impairment on driving performance and to determine whether driving performance can be predicted by laboratory-based vision tests. In this study three groups of subjects were tested including young visually normal subjects, old visually normal subjects and older subjects with visual impairment. All subjects had a current driving licence and were legally eligible to drive. Visual performance was assessed using a battery of visual function tests including the Pelli-Robson chart, disability glare test, Useful Field of View (UFOV), and reaction times (RT). Driving performance was assessed on a closed-road circuit to measure peripheral awareness, manoeuvring, reversing, central and peripheral RTs, speed estimation and time to complete the course. The results demonstrated that visual impairment and age had a significant effect on driving performance (p<0.05), where the subjects with visual impairment had poorer driving performance (p<0.05) than either the old or young normal subjects, and the old subjects had poorer driving performance (p<0.05) than the young. Similarly, the visual performance of the old subjects (with or without visual impairment) was significantly worse (p<0.05) than the young subjects. The older subjects had lower Pelli-Robson scores, higher disability glare, longer RTs and reduced ability on the UFOV task. A significant relationship between driving scores and visual performance on the Pelli-Robson chart and UFOV was found across the groups.
Samenvatting