Association between higher order visual processing abilities and a history of motor vehicle collision involvement by drivers ages 70 and over.

PURPOSE

To examine in a population-based sample of 2000 drivers aged 70 years and older, the independent association between higher order visual processing impairment and motor vehicle collision (MVC) rate during the prior 5 years.

METHODS

Three higher order visual processing screening tests were administered since previous research found associations between impaired performance on these screens and MVC involvement. They included an estimate of visual processing speed under divided attention conditions (useful field of view [UFOV] subset 2); Trails B, a paper and pencil test of visual processing speed also involving problem solving, executive function, and working memory; and the visual closure subtest of the Motor Free Visual Perception Test (MVPT) examining the ability to recognize objects only partially visible. Potentially confounding variables were also assessed including demographics, general cognitive status, visual acuity, and contrast sensitivity. MVC involvement was determined by accident reports from the Alabama Department of Public Safety, and driving exposure was estimated from the Driving Habits Questionnaire.

RESULTS

MVC rates (for at fault and all MVCs) were significantly higher for those older drivers with impairments in any of the three visual processing screening tests. After adjustment for potentially confounding influences, the association between MVC rate and Trails B remained significant, whereas the association with MVPT and UFOV did not.

CONCLUSIONS

This population-based study of drivers aged 70 years and older suggests that a paper and pencil test assessing higher order visual processing skills is independently associated with a recent history of MVC involvement.