Glare disability and driving safety

Purpose: Increasing investigation of the visual elements of safe driving environments may be of great benefit to society. Visual disability appears to be only one of many visual factors related to traffic accidents. The purpose of this article was to examine the type of visual impairment mediated by the increased glare sensitivity in adult drivers using the original halometer glare test. Methods: In this article, the visual sensory, cognitive and motor functions relevant to driving, their measurement, the epidemiology and prevention of age-associated functional impairments and the relationship of functional impairments to both self-reported driving and the imposition of legal restrictions are reviewed. Results: The problem of night and tunnel driving is the most urgent in relation to the effects of glare from vehicle headlights on motion perception of drivers. The reduced mesopic vision and increased sensitivity to glare are accompanied by an increased risk of nighttime accidents. Elderly drivers and patients with beginning cataract cannot sufficiently fulfill the criteria for night driving ability because of contrast and glare sensitivity. It is indispensable for the parameters mentioned to be carefully measured and for drivers to be informed that night driving ability may be impaired, even if visual acuity is sufficient. Conclusions: It would be advisable for traffic safety if simple tests for contrast and glare sensitivity were implemented for vehicles and/or were regularly added to the requirements for a driver's licence, at least for older drivers. The age, functional status and test result limits should be defined to avoid a risk factor in traffic. Copyright (C) 2003 S. Karger AG, Basel.