The way Dorothy Wulfers sees it, only two minds are qualified to decide when it's time to give up the keys to her Buick LeSabre: hers and God's.

Wulfers, 87, learned to drive a Model T Ford when she was 15. Seven decades later, driving remains a simple pleasure, whether a morning run to Wal-Mart or a 112-mile trek to Parkersburg for tea with the women's club.

"If there would become a doubt in my mind, then I would give it up," Wulfers said. "But I'm self-assured, I'm confident, and I don't see why I should."

Increasingly, though, states are taking a look at older motorists. They are concerned that vision, reaction time and other driving skills have diminished. At least 22 states have laws singling out older drivers for special attention.

"It's one of the emerging issues with the aging of America, keeping people both safe and mobile," said Bella Dinh-Zarr, national director of traffic safety policy for AAA. "But is legislation really the answer? No, because there's not enough information."

Between 1990 and 2000, the number of Americans over 65 jumped 12 percent to more than 35 million. According to the U.S. Census, the older population grew in every state.

California, Florida and New York have the highest number of older drivers. Florida, Pennsylvania and West Virginia have the largest percentage of people older than 65: 17.6 percent, 15.6 percent and 15.3 percent, respectively.

Monitoring and assisting older drivers is an issue for every state, said DaCosta Mason, national coordinator of consumer issues for the AARP. "Research suggests that older persons are more likely to be involved in a crash," Mason said. "The problem is we don't know at what age deterioration begins."

Illinois and Rhode Island require road tests for drivers older than 75 who want to renew their licenses, while 15 other states have an accelerated renewal schedule. At least five states have stopped mail-in renewals for older drivers.

The most common tool is vision testing. In Virginia, vision testing drivers older than 80 went into effect July 1.

Mason said the AARP questions the nature of vision tests and who's conducting them. Most vision tests fail to measure contrast and peripheral vision, both of which could be factors in an accident.

The AARP believes all drivers should be tested regularly and fully, but Mason said most cash-strapped states single out older drivers.

Several states prohibit age-based testing, including Nevada.

"We've not really identified senior drivers as being a problem on the road," said Tom Jacobs of the Department of Motor Vehicles in Carson City. "Bad drivers come in all age groups, and there are good drivers out there who are 80 years old."

Nevada allows older drivers to voluntarily restrict their licenses to road-tested routes so they can travel to church, the grocery store or relatives' homes.

Steve Dale, a spokesman for the West Virginia Division of Motor Vehicles, said lawmakers in his state oppose renewal vision tests for any driver, regardless of age. With little public transportation in West Virginia, they fear rural residents would be stranded.

The state has a medical advisory board where relatives, doctors or police can refer drivers after an accident. The board decides whether to retest the driver and often orders a medical evaluation. About half of those referred lose their licenses.

The American Medical Association, AAA and other safety groups have developed a physician's guide to help answer the question of whether older people are fit to drive. AAA is also developing a self-screening program that older drivers can use at home, with just a computer and a friend. Now in pilot testing, Dinh-Zarr said it should be ready for distribution next year.

Selma Sauls, management analyst with the Florida Department of Highway Safety and Motor Vehicles, said her state could not wait to get started because it was headed for a crisis.

Seven years ago, Florida formed a task force that brought all stakeholders to the table: state agencies, doctors, care-givers, transportation providers, AARP and seniors.

Once the agencies got past finger-pointing and budget-guarding, they began linking transportation and other state services to help stranded ex-drivers.

And by agreeing to focus on risks that related to a person's medical condition rather than age, "We found out that we weren't poles apart," Sauls said. "There came to be a trust, that we were not out to get seniors, that we were looking out for their overall well-being."

In West Virginia, Dorothy Wulfers, 87, is behind the wheel of her Buick.