PHOENIX (AP) -- Once a week, Ruthie Culver steps into her golf cart and drives the three miles or so from her home to Banner Boswell Medical Center in Sun City, where she volunteers.
If it's raining, she gets behind the wheel of her Buick.
Culver is 102, and startling though it may be to find someone her age still driving, there is this: She is not the state's oldest driver. And this: Older drivers may not be quite the hazard to others that younger drivers imagine them to be, according to a recent national study that yielded unexpected results.
AP Photo - - Ruthie Culver, 102, drives her golf cart home after volunteering at Banner Boswell Medical Center in Sun City, Ariz. Older drivers may not be quite the hazard to others that younger drivers imagine them to be, according to a recent national study that yielded unexpected results. Of the 4.3 million Arizonans with active driver's licenses, 77 are 100 and older.
Of the 4.3 million Arizonans with active driver's licenses, 77 are 100 and older. The oldest is a 105-year-old Phoenix resident. Thirty-nine are men, 38 women.
"I was a little surprised by those numbers," Cydney DeModica, spokeswoman for the Arizona Department of Transportation's Motor Vehicle Division, said after a check of the division's records, "but not because I think they're necessarily bad drivers. We know people are living longer, healthier lives now."
If official identification is older drivers' only wish, they can opt for an Arizona non-driver's ID card, which DeModica's 93-year-old mother has.
Many, though, no doubt share Culver's determination to remain independent, and a driver's license -- used or merely tucked away "just in case" -- is a symbol. A volunteer at Boswell since she was 96, Culver's not about to let stormy weather or her age keep her away now.
"I hope I can keep driving as long as I keep active and as long as I feel safe," she said.
Names and other identifying details about license holders are protected by Arizona law (Culver volunteered her driving information), so it's not known how many of the other 76 centenarian drivers are still on the road, how often or under what circumstances.
All renewed their licenses in person, as required for those 70 and older, DeModica said, "but medical conditions being what they are, 30 of them could be in assisted living or nursing homes by now."
The 105-year-old's license was renewed most recently in 2005, she said.
In the five-year stretch between renewals mandated for Arizona residents 65 and older, some decide to stop driving and some have that decision made for them.
No state imposes an upper age limit for driver's licenses, according to the Arlington, Va.-based Insurance Institute for Highway Safety, although several states add requirements for seniors.
"It's indisputable that various impairments set in as we age," said Anne McCartt, the institute's senior vice president for research.
Less clear is how to identify people who shouldn't be driving, she said. Vision tests and certain other measurements so far have not proved sensitive enough to predict risk accurately.
Arizona's MVD receives thousands of letters a year from drivers' physicians, family members and responders at accident scenes who report troubling signs of declining driving ability, DeModica said. Those cases are referred to the division's medical review program, the nation's first.
"Crash frequency increases at age 70 to 75," she said. "But driving ability can be compromised at any age and by health conditions like diabetes, stroke or serious head injuries, so we have to have lots of built-in safety nets."
Arizona residents renewing their license must pass a vision test and fill out a renewal application. The in-person renewals starting at age 70 give MVD employees an opportunity to spot signs of cognitive decline or impaired mobility in applicants and to require road or written tests as needed.
No such signs were noted the last time Culver renewed her license.
"I passed everything," she said. "I was very lucky."
The 5-foot-tall Culver, whose delicately applied eye shadow matches her blue eyes, needs glasses for reading only and never has had cataracts. She takes no medicines and has no chronic health conditions, although her hearing is not as sharp as it used to be.
A widow with no children, she lives alone, has logged more than 1,200 volunteer hours at Boswell, walks with a cane, gardens and gets herself to the library and to bridge games with friends.
Has anyone ever told her she's too old to drive?
"The police have never told me that," she said. "And, knock on wood, I've never had an accident."
Culver's experience reflects a surprising downward trend in injury-causing and fatal crashes among drivers 70 and older, as reported by the Insurance Institute.
A study released by the institute in December revealed that older drivers' involvement in fatal crashes declined 21 percent from 1997 to 2006. The decline occurred even as the number of older drivers grew 10 percent and their annual mileage increased 29 percent.
However, because they still drive fewer miles annually than younger people do, their fatal crash rate per mile traveled is second only to the youngest drivers, the National Highway Traffic Safety Administration says.
Reasons for the decline aren't clear, said McCartt, of the Insurance Institute, but may include safety features in newer cars, older drivers' choosing to limit nighttime driving or make other adjustments, and their improved health, which makes them better able to survive a crash.
Fragility makes older drivers a danger mostly to themselves, she said. Seventy-five percent of those who die in crashes involving drivers 70 and older are the drivers or their older passengers.
"A lot of what drives the rates up is not their likelihood to be in a crash," McCartt said, "but the fact that they're less likely to survive than younger people in a crash of the same severity."
Dalvin Palmer, of Sun City West, has taught AARP driving safety courses since 1992 to help improve the odds for older drivers.
Palmer, 69, just returned from a 3,500-mile road trip with his wife, encountering nary a problem.
"As we get older," he said, "our reaction times slow, our vision and peripheral vision decrease, our hearing decreases. But a person can compensate for all that with common sense. I know people in their 20s and 30s who I wouldn't ride across the street with."