Driving gray.

Older drivers are generally safe drivers. They are more likely to wear safety belts and less likely to drive while impaired. But aging brings physical changes that can hinder driving. With slowing reflexes, reaction time increases significantly between the ages of 35 and 65. Some older drivers also have deteriorating eyesight and hearing.

Thirty-four states use medical review boards or medical advisory boards--made up of health care professionals and physicians--to help determine when a driver should be taken off the roads for health-related reasons. Typically, these boards do not decide based solely on age. The boards also recommend licensing standards.

California, Delaware, New Jersey, Oregon and Pennsylvania have mandatory physician reporting requirements. Physicians in these states must report patients with conditions that may cause lapses of consciousness. The reports are confidential, and most states provide civil and criminal immunity for the physician. In Pennsylvania, a physician who fails to inform the proper authorities about a medically impaired patient could be found negligent if the driver is involved in a crash.

States are also turning to driver's licensing laws for older drivers. Some states use accelerated renewal cycles, vision testing and in-person renewals rather than online or mail renewals for older drivers. Illinois and New Hampshire require road tests for drivers over 75.

Last year, 11 states debated proposals targeting the safety of older drivers. Illinois, for example, passed a law requiring the Department of Transportation to study the transportation needs of senior citizens. Indiana, New Hampshire and Oregon passed legislation regarding medical issues and driving. A new law in Indiana prohibits the Bureau of Motor Vehicles from suspending or revoking the license of a person with suspected medical issues until a thorough investigation has been conducted. And New Hampshire established a medical/vision advisory board to help the motor vehicle division with policy decisions.

Driver training can also help ensure the safety of older drivers. At least 35 states have passed laws that require insurance discounts for older drivers who take re-education courses. Some insurance companies voluntarily offer such discounts. These courses help older drivers renew their driving skills and compensate for slower reflexes and other abilities that may have deteriorated due to the aging process.

Another way to help older drivers stay safe is to improve the driving environment. The Federal Highway Administration has established guidelines for older driver-friendly road designs, such as intersection improvements and better signage, lighting and road markings. These improvements will help not only older drivers but also drivers and passengers of all ages.