Eye Disease and Driving Performance: Correlates Between Insight and Capability in Drivers with Glaucoma.

The prevalence of visual impairment is higher in older populations. Due to the highly visual nature of the driving task, the impact of aging on visual function is of particular interest in the context of road safety. Although it has been suggested that older drivers compensate for the decline in their driving abilities, there has been little research which has related the compensatory driving behaviours to actual driving measures of elderly drivers who have visual impairment resulting from eye disease. In addition, current research on the driving performance of people with eye disease is limited. Importantly, it has been reported that people with eye disease often have limited insight into their condition and hence are unlikely to compensate for it. This study aims to address several issues: what impact does eye disease have on driving behaviour, is the impact of eye disease on driving mediated by awareness, and what compensatory behaviours do drivers with eye disease display compared to age-matched controls? Participants were elderly people with glaucoma who were currently driving. Driving related information was collected with questionnaires included the Activities of Daily Vision Scale, Driver Behaviour Questionnaire and a Driving Exposure questionnaire. Visual function tests included visual acuity, contrast sensitivity, visual fields and tests of glare sensitivity. Driving performance was assessed on a closed road circuit. Data collected to date indicates little correlation between self-rated ability and actual performance. Drivers with visual impairment perform worse at driving tasks such as obstacle avoidance and sign detection. It is envisaged that this study will guide policy decisions concerning advice for drivers with eye disease