Newswise — Death rates for older drivers in Florida decreased following passage of a vision screening law for drivers age 80 and older, according to new research from UAB (University of Alabama at Birmingham). In findings published in the November issue of Archives of Ophthalmology, the UAB researchers say that, while there is little evidence of an association between vision and motor vehicle collisions, the death rate among older Florida drivers has decreased significantly since the law requiring drivers age 80 and older to pass a vision test went into effect in 2004.
Gerald McGwin, Ph.D., professor in the Department of Epidemiology and associate director of UAB's Clinical Research Unit in the Department of Ophthalmology, and colleagues used data from the National Highway Traffic Safety Administration and the U.S. Census Bureau to study rates of motor vehicle collision deaths among all drivers and older drivers in Florida between 2001 and 2006. They also compared these rates to those in Alabama and Georgia, neighboring states that did not change their legal requirements during this time period.
While overall death rates for all drivers climbed slightly during this period, the fatality rate for older drivers fell 17 percent. Fatality rates for older drivers in Alabama and Georgia did not change.
"There are a number of possible explanations for the decrease," McGwin said. "Perhaps the most apparent reason is that the screening law removed visually impaired drivers from the road, however, our findings suggest the situation is significantly more complex."
McGwin said about 93 percent of drivers who sought a license renewal were able to obtain one, suggesting that only a small percentage of drivers were removed from the road for failing the vision test. He also suggests that the visual ability of older drivers may have been improved by the screening law, as drivers who failed to pass the test at first may have sought vision care and, following vision improvement, subsequently passed the test.
Another possibility for the decrease is that drivers who recognized their own visual impairment may have chosen to not seek a license renewal and voluntarily stop driving.
"Ultimately, whether the vision screening law is responsible for the observed reduction in fatality rates because of the identification of visually impaired drivers or via another, yet related, mechanism may be inconsequential from a public safety perspective," McGwin said. "However, the importance of driving to the well-being of older adults suggests that isolating the true mechanism responsible for the decline is in fact important."
He says future research identifying this mechanism would allow states to implement laws that accurately target high-risk drivers while allowing low-risk older drivers to retain their mobility.
NOTE: The University of Alabama at Birmingham is a separate, independent institution from the University of Alabama, which is located in Tuscaloosa. Please use University of Alabama at Birmingham on first reference and UAB on second reference.
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