TSCNewsletter:Extending Safe Driving Years workshop

Making the Roads Safer for
Older Drivers
Report from the Traffic Safety Center's Extending Safe Driving Years Workshop

The UC Berkeley Traffic Safety Center convened the Extending Safe Driving Years Workshop on June 12, 2003, to explore the implications of the demographic fact that more older drivers are on the road than ever before, and that today's and tomorrow's older Americans will rely on the car more than any previous older generation.

"Some of these people will need alternatives to driving, but many of them will be driving," noted the Center's Jill Cooper in her opening remarks. "So, in the spirit of maximizing the range of mobility and safety options for older adults, we decided to focus this workshop on extending safe driving years." The object, she said, is not to simply suggest older adults take transit more often or use other alternatives, but to seek ways to "extend the ability of older adults to drive longer-and more safely."

"Toward this end, our goals for today are to highlight some UC Berkeley research in this area and to generate priorities for discussing applications of this research to the traveling environment, to vehicle design and operation and to personal behavior," Cooper said.

Some 60 people attended the workshop. The diversity of the audience reflected the organizers' intent to bring together a wide range of experts and practitioners. Attendees included representatives from three carmakers, staff from the California Department of Transportation, the California Office of Traffic Safety, the California Department of Health Services, the Department of Motor Vehicles, law enforcement agencies, municipal and regional transportation agencies, agencies for the aging, and community members and advocates, in addition to UC Berkeley researchers and faculty from the Traffic Safety Center (TSC), the Institute of Transportation Studies (ITS), the Partners for Advanced Transit and Highways (PATH) program, the Center for Information Technology Research in the Interest of Society (CITRIS), the California Center for Innovative Transportation (CCIT), the Center for Injury Prevention Policy and Practice, the Schools of Optometry and Public Health, and the Departments of Civil and Environmental Engineering, City and Regional Planning, and Molecular and Cell Biology.

Today's older Americans have achieved a greater degree of mobility and have extended that mobility later in life than any previous generation through their reliance on the car. Driving is the main means of mobility for all people, including older adults. Though it is critical to explore alternatives, driving is likely to continue to be the preferred mode of transportation for this group. Public health concerns, therefore, have emerged about how to keep the driving environment as safe as possible for them and other road users. These concerns are especially pressing given the anticipated explosion in the population of people older than 65 and the large number of drivers above that age. In California, the share of people older than 65 went from 10 percent in 1990 to 15 percent in 2000, and by 2020 the older adult population will have roughly doubled from 1990 levels, according to a 2002 report from the California Task Force on Older Adults and Traffic Safety.

This new generation of older people also drives more than its predecessors, explained ITS Director Martin Wachs, who is Professor of Civil Engineering and City and Regional Planning at Berkeley. Wachs gave the keynote address, in which he presented an overview of older Americans' driving patterns, which are influenced by a number of factors, including their tendency to age in place in suburban and rural settings that have few transportation alternatives to the car, and the demographic trend that is seeing more women driving into their older years as a result of women's earlier gains in equality of opportunity. He noted that older drivers have lower rates of crashes as measured by the number of older drivers, but higher rates per miles driven. They also tend to be more of a risk to themselves than to other drivers. Wachs also noted that enhancing their safety was likely to be more complicated than imposing arbitrary age restrictions or licensing tests and warned such measures could prove to be unjust and impractical. View the PowerPoint presentation.

Research presentations were made by Judy Geyer, TSC Research Associate, Stanley Klein, Professor of Vision Science at the School of Optometry, Christopher Nowakowski, of PATH, and David Ragland, TSC Director.

Knowing Where the Danger Lies

Geyer said it was important to understand the components of crash risk so policies could be more precisely matched to causes. She explained the risk of crashing as a product of three separate components-rates of exposure, the crash rate per unit of exposure, and the fatality/injury rate-and recommended that more research be conducted in order to better understand how aging affects these components. For example, when older drivers "self-regulate" by choosing to reduce their night driving, that affects exposure; a decline in reaction time caused by physiological changes has an impact on crash risk; and an increase in fragility due to osteoporosis affects fatality risk. View the PowerPoint presentation.

Learning How Older Eyes See

Klein described a series of research initiatives at the School of Optometry that are relevant to older driver safety. He stressed the importance of bringing researchers from a variety of areas together to devise ways for older drivers with declining vision to drive safely for a longer time. Klein mentioned the work of researchers such as his colleague at the School of Optometry, Ted Cohn, who is working on ways to make lights on buses easier to see; Ian Bailey, one of the world's leading experts in low vision and a developer of low vision aids; and Marty Banks, the creator of a glove to improve hand-eye coordination. Klein also mentioned the work of Brian Barsky, a computer scientist whose simulations of what the world looks like to those with impaired vision could be helpful in designing signs and signals to be easier to see and understand.

Klein also spoke of his own research dealing with glare assessment. "It turns out that there's a large fraction of the population that have more scattering of light than they're aware of," meaning that they are nearly blinded by certain kinds of light, such as low rays at sunset. However, there exists no reliable, easy test to determine sensitivity in this area. Engineers and researchers in the optometry field, Klein said, should come together to devise tools for assessing and improving vision and ways of making vehicles and environments safer for older adults. View the PowerPoint presentation.

Machines that Fit People

Nowakowski presented his and colleague Delphine Cody's work on human factors elements in driving and driver safety, describing human factors as "a melding of engineering and psychology" to make systems better fit the needs and capabilities of humans. In the case of older drivers, that means incorporating aging bodies' capabilities in such elements as vehicle design. Larger buttons spaced farther apart on the dashboard, larger fonts on the speedometer, and seats that automatically pull back when the door is opened to make a car easier to load and unload are among the possibilities.

More sophisticated solutions include technologies that help reduce driver errors, especially those more frequently experienced as drivers age. Estimating speed and processing complex situations in adequate time to react are two areas where machine technology could help, and research at PATH is addressing some aspects of this, he said. In addition to devices to make intersections easier to negotiate, researchers are working with instrumented cars to record driver behaviors and help researchers identify specific tasks where technology could intervene to make them safer. Nowakowski also pointed out that advances aimed at making older drivers safer would also aid the driving population in general. View the PowerPoint presentation.

Aging and the Desire to Drive

Ragland's presentation focused on "Study of Physical Performance and Age-Related Changes in Sonomans," a community-based longitudinal study that surveyed 2,100 of Sonoma's 3,500 residents aged 55 and over. The research, which was done by Ira Tager and William Satariano, of the School of Epidemiology at Berkeley, investigated the connections between medical status and driving habits among the elderly, a link rarely studied, Ragland said. They monitored the participants' social activities, driving patterns, and health status over the course of 10 years, from 1993 to the present. Specifically, researchers looked at how social needs-such as employment status and recreation-transportation resources, and physical condition influenced the subjects' driving patterns. Their questions included how health variables affect driving behavior and driving safety, and whether driving cessation produces depression or other negative outcomes.

Vision, Ragland said, was "by far the most frequently mentioned" medical reason respondents cited for reducing their driving. Almost 40 percent of participants indicated that vision problems limited their driving, and that percentage increased quite dramatically with age. The participants also cited non-medical reasons for reducing the amount they drove: having fewer places to go, due to retirement and a decrease in daily activities, and fear of crashing or being victimized by crime.

Researchers found that depression was heavily linked to driving cessation, particularly for men. Ragland suggested that further research be devoted to finding ways for older adults to remain mobile after they cease driving. One coping mechanism, Ragland said, might be to move to a location where driving is not essential for social interaction. Relocation, however, is not a very common solution. "Most people do grow old in place," Ragland said. "Even though the stereotype is that people move to Florida or to Rossmoor [an area retirement community]."

On the heels of the Sonoma study, Ragland said, more research is also needed on driving behaviors and the relation of non-medical conditions to driving patterns. He urged researchers to conduct studies that look specifically at driving and mobility, but admitted that such studies can be expensive. Where funding is limited, Ragland suggested that researchers develop "standard measures of driving" that can be plugged into other epidemiological studies to determine the links between driving and health risk. He also pointed out that advances that will help older adults will aid everyone, meaning that it is good public policy to pay attention to this issue. View the PowerPoint presentation

Successfully Growing Old

Luncheon speaker Paola Timiras, Professor Emerita of Cell and Developmental Biology at UC Berkeley, focused on the interrelation of mobility and health. Timiras explained that while vision and cognitive ability tend to deteriorate as people age, the rate at which they decline depends on a number of factors. Genetics certainly determines the way we age, but environment, researchers have found, plays a greater role than was previously thought. "The nervous system is very plastic throughout your life. With better food, better exercise, education, the brain can improve," Timiras said. There is a "successful" aging and a "usual" aging, and environmental factors are critical in insuring that one ages successfully.

Mobility, Timiras said, is linked to successful aging in many ways. Driving can foster a sense of independence, which can produce a better outlook on life. If the ability to drive is lost, the older adult may be prevented from engaging with life and seeing friends, a loss that can lead to depression. "How can we engage in modern life if we cannot communicate?" Timiras asked. "How can we communicate if we cannot meet? And how can we meet if we cannot drive?"

Driving can also help keep certain faculties sharp. Timiras explained that, contrary to popular perception, the stress associated with driving can have a positive effect on the nervous system, and can in fact promote better health in older adults. Researchers have had various views on stress in the past, saying first that stress can be good, then emphasizing its negative effects. But recently, Timiras said, opinion has shifted back to a positive view of stress. "In the last few years, stress is again seen as a very important response to the change in the environment, which not only allows you to survive unfavorable conditions but stimulates you to respond better. The stress response is now seen as a very favorable condition." The very faculties-vision and cognition-whose deterioration is said to make driving difficult can in fact be improved through the act of driving.

Practice and Theory Converge

Marilyn Sabin, of the California Office of Traffic Safety, facilitated the afternoon panels and audience discussions. Panelists included Barbara Alberson, from the California Department of Health Services, Patti Yanochko, of he Center for Injury Prevention Policy and Practice, Jim Misener, of PATH, and Ruzena Bajcsy of CITRIS.

This discussion was organized around three types of interventions: modifying individual behaviors, changing the environment, and re-designing vehicles to make them safer to drive for older people.

Alberson and Yanochko addressed environmental modifications. They engaged the audience in discussions of the importance of roadway design, including applying knowledge from optometry and human factors research to make roads safer. Another approach is promoting pedestrian-scaled communities to provide an alternative to cars, implementing systems at intersections to make it easier for drivers to judge when it is safe to make a maneuver, such as turning left across oncoming traffic, and incorporating older driver safety concerns in implementations such as Caltrans' 25-Year Plan and making use of recommendations in the Federal Highway Administration's 2002 "Guidelines and Recommendations to Accommodate Older Drivers and Pedestrians."

Yanochko and Misener discussed improved transit systems as alternatives to cars for older drivers, driver re-education, driver self-assessment procedures, and devices to make intersections easier to negotiate. Members of the audience added concepts such as family assistance programs, self-assessments to measure memory and cognition such as those devised by the American Association of Retired Persons, and the experimental three-tiered older driver assessment program being tested by the California Department of Motor Vehicles.

In the final segment, Misener and Bajcsy presented highlights of a research platform intended to develop in-vehicle devices to assist older drivers. They included use of crash dummies that resembled older drivers more closely, advanced sensors and collision avoidance systems, and computerized systems to adjust the devises used to operate cars to the physical capabilities of individual drivers. Audience discussion included an exchange with researchers from three automakers discussing some of the possibilities and barriers faced when trying to design cars to aid older drivers while still having them be commercially successful.

"It's very difficult to separate out the vehicle, the individual, and the environment," Sabin noted. The group agreed involvement by a broad range of experts, policymakers and members of the public would be needed to arrive at usable solutions and set priorities for their implementation.

Related Links:

Speaker information and detailed presentation summaries on the TSC website

AARP (American Association of Retired Persons)

California Office of Traffic Safety

California Department of Motor Vehicles

Caltrans (California Department of Transportation)

California Highway Patrol

California Center for Innovative Transportation (CCIT)

Center for Information Technology Research in the Interest of Society (CITRIS)

Center for Injury Prevention Policy and Practice

Institute of Transportation Studies

Partners for Advanced Transit and Highways (PATH)

School of Public Health

School of Optometry Visual Detection Laboratory