Some older drivers have experienced age-related changes that undermine their ability to drive safely, so may pose a hazard to themselves and to other road users. Older adults may reduce their risk by avoiding driving under difficult conditions including night and rush hour driving, but the current understanding of the relationship between age-related functional changes and risky driving behaviors is inadequate to support development of effective countermeasures.

This study updates and extends our understanding of how age-related functional deficits can influence driver performance, and in turn crash risk for older drivers. It also examines the potential for behavioral countermeasures targeted to the remediation or accommodation of such deficits to attenuate critical errors in performance, and thus to reduce crash risk. A taxonomy table displaying the demonstrated and inferred links between these variables was developed as the central product of this research.

The taxonomy table is a resource that provides at-a-glance, state-of-the-knowledge information to assist researchers, health care practitioners, and others concerned about older driver safety to identify particular risk factors, and what can be done to reduce the risk.