Epidemiology: Risk Factor Research

Time Since License Renewal and Risk of Motor Vehicle Crash in Elderly Drivers

Principal Investigator: Thomas Koepsell, M.D., M.P.H.
University of Washington Department of Epidemiology
Funding Source: Centers for Disease Control and Prevention (HIPRC Center Grant)

How long a driver's license remains valid before it must be renewed varies widely from state to state. Some shorten the time between renewals for older drivers; most do not. The time between license renewals is a public-policy choice, balancing the risk of crashes caused by drivers who have become impaired against the cost and inconvenience of more frequent renewal checks. The fact that renewal intervals vary among states from three to six years probably stems in part from uncertainty about this relationship, and about how it may vary by age. This study investigates a key factor affecting this balance: the relationship between crash risk and time since last license renewal.

^ Back to Top