Issues in Science and Technology, Online A Publication of National Academy of Sciences National Academy of Engineering Institute of Medicine University of Texas at Dallas
  • Home
  • Back Issues
  • Search


Transportation Safety

A. JAMES McKNIGHT

Too Old to Drive?

We must provide the elderly with easy mobility while protecting them from driving risks.

For every mile they drive, people age 75 or older are more likely to be seriously injured or killed in an automobile accident than are drivers in any other age group except for teenagers. Contrary to common knowledge, the problem is not that the elderly as a group are involved in appreciably more accidents per mile traveled than are their younger counterparts. Indeed, up to age 75 there generally is no significant decline in the mental and physical abilities needed to drive a car without impeding traffic or endangering public safety. Even beyond that age, they are not appreciably more likely to have an accident.

Rather, elderly drivers are simply more fragile. Thus, when involved in an accident, they are more likely to be seriously hurt. The threat that elderly drivers face is mitigated to some extent by a decrease in the miles they drive, to about a third of the miles they compiled when they were middle-aged. But the fact remains: Elderly drivers take a significantly greater risk every time they get behind the wheel.

Yet in matters of transportation policy, old age, like the weather, is more often the subject of talk than action. When a serious accident caused by an elderly driver makes the news, the public response often tends to be, "Get the old folks off the road!" But aside from raising questions of basic fairness, pushing old folks off the road would only raise another problem: how to get the elderly around. The need to move from one place to another does not end or even substantially decline with advancing years. There was a time when old people could walk to the market or drug store. However, today's older generation is the one that led the post-World War II flight to the suburbs, where stores and other facilities are miles away, often accessible only by roads lacking any room for pedestrians. Although some of the elderly now spend their advancing years in retirement communities with easy access to needed facilities, most of them have stayed put and are as dependent on the car for meeting daily needs as they have ever been.

The challenge facing the transportation community is how to provide the elderly with the easy mobility they have enjoyed throughout their lives, while at the same time protecting them from the risks they face from driving. Already tough enough, this task will become increasingly formidable. People over age 75 make up one of the fastest-growing segments of the U.S. population, and this segment will only expand as the first baby boomer cohort passes beyond that age. In addition, projections are that an increasing proportion of the elderly will continue to drive and that they will rack up more annual mileage per person than ever before. At the same time, there has been little increase in the amount of public resources being committed to meeting the nation's alternative transportation needs; not only the needs of the elderly but of society at large.

Efforts to improve safety for elderly drivers fall into several main categories: making automobiles safer; making roads safer; assessing drivers' skills and, where necessary, either offering remedial help or restricting or revoking driving privileges; and developing alternative means of transportation, both public and private.

Technological advances

Recent technological advances show considerable potential for making cars easier and safer to drive. For example, modifications in airbag design that adjust the rate of inflation to the severity of impacts will help reduce the chances of injury from the airbag itself, something to which the elderly are particularly vulnerable. So too will the installation of additional airbags in side panels, footwells, and other places where impacts occur. Sophisticated cruise control systems are reaching the market that will automatically keep cars at a safe following distance. Also becoming available are infrared and ultraviolet systems for displaying critical elements of the scene ahead in a way that enhances their visibility, particularly at night or in heavy rain. In addition, a variety of devices under development will warn drivers of collision situations at intersections, in merges, and during backing: conditions that are troubling to some elderly drivers. Other devices will direct the headlights along a curved path as a car turns, a feature that will be of particular benefit to the elderly with poor night vision, especially when they travel unfamiliar routes.

Although such advances may prove of considerable benefit to the elderly, there is some concern about how well this population will adapt to new technology, particularly the sophisticated electronics of what is coming to be known as the "Intelligent Transportation System." Will older drivers be willing to learn new tricks? Will they be able to understand these new systems and carry out the physical manipulations involved in using some devices, all the while providing sufficient attention to surrounding traffic? There is reason for optimism. As years go on, much of the older population will have had enough experience with computers and other electronic devices not to be intimidated by the fruits of emerging technology. Thus, although the concerns are certainly merited, how well they are satisfied will likely depend on how well designers accommodate variation in the abilities of users. Unfortunately, like many other technological advances, the rush to gain competitive advantages often precludes the testing needed to detect and deal with inadequacies of design or preparation required in facilitating implementation. Filling this gap offers a fertile field for research.

Technological and design advances also are making highways safer, as recent years have seen increasing emphasis in research on the needs of older drivers. The U.S. Department of Transportation now requires that older drivers be included in all studies that it funds and that the results of all studies be analyzed in terms of age. The National Institute on Aging also has supported research on the relation of age-related declines in physical and mental abilities to aspects of driving influenced by highway design. Drawing on the results of these and other research efforts worldwide, the Federal Highway Administration has recently published the Older Driver Highway Design Handbook, which provides recommendations for highway enhancements that are capable of improving the safety of all road users, but particularly the elderly. For example, because older drivers have relatively more serious accidents while making left turns, roadways can be improved through designs that provide drivers with better views of oncoming traffic. In work zones, older drivers tend to make necessary lane changes at a much later time, particularly at night, suggesting the need for earlier and more conspicuous warnings. Highway signs can be made easier for the elderly to see and read by using fluorescent lighting, reduced background clutter, increased size and reflectivity of letters, certain fonts for text, and symbols instead of words.

However, the costs of incorporating all of the recommended improvements into the roadway infrastructure go well beyond the budgets of state and local highway agencies. Before accepting this burden, the highway community can rightfully expect the proposed advances in highway design to be evaluated for their actual benefit to the driving public. Research is needed to determine what effect various age-based design changes actually have on the target populations. For example, where does the ability to read signs at a greater distance really matter, and where can drivers easily and safely wait until they are closer? Moreover, the benefits of various highway design changes do not come at equal cost, and additional cost-benefit studies are needed to help highway planners with prioritizing changes.

Although some questions remain about new technologies for improving cars and highways, the issues, for the most part, are relatively straightforward. There is little downside to what technology has to offer the elderly. However, there are several critical issues surrounding the assurance of safe mobility for the elderly that are still the subject of debate and uncertainty. These issues include:

  • How can we identify the older drivers who are at increased risk? It is not difficult to determine who should not be driving after a serious accident occurs. But the matter of spotting high-risk drivers before they suffer any damage has not received adequate attention from the public agencies and officials who regulate driving. A related question is, what factors are most critical in placing an elderly person at increased risk? Although science has furnished an array of measures that point to physical and mental abilities that decline with age and may play a role in accidents, science cannot yet parlay such findings into foolproof ways of deciding which particular individuals should not be driving.
  • How do we transport people who should not drive? Public transportation systems intended for use by the elderly do not approach the convenience of the car to which they've grown accustomed.

Identifying at-risk drivers

Decisions about when older drivers are at increased risk of being involved in a serious accident are most often made by the drivers themselves. The overwhelming majority of the elderly who are no longer capable of handling a car recognize it. Most of them begin to feel uncomfortable in traffic and react by driving less and less until they simply do not drive at all. When their license comes up for renewal, they let it expire. Drivers who do not recognize their inadequacies are a small part of the problem, but one that the driving public clearly believes must be dealt with.

Determining who can still drive safely, who should be restricted in their driving, and who should not be driving at all could be made simple: Test everybody. But most state licensing agencies now face tightened budgets, along with increases in responsibilities. As a result of this squeeze, the majority of states have been forced to curtail the frequency and extent of driver testing. The laxity of current license practices encounters little opposition from a public spared the bother of having to take periodic tests. Yet when an accident exposes the ineptitude of an elderly driver, the same public expresses wonder how such a menace manages to stay licensed.

Spotting high-risk drivers before any damage is done has not received adequate attention from regulators.

There are two procedures by which elderly drivers can be called on to demonstrate their abilities: periodic renewal of the driver license and reports to licensing agencies of drivers whose abilities seem questionable. Both routes raise issues of license policy. Less at issue but still in need of examination are the means by which the elderly may voluntarily seek assessment of their abilities.

License renewal. For most drivers, the process by which licenses are renewed is relatively painless. In many states, drivers with clean records rarely have to see the inside of a licensing office; when they do, it seldom involves more than taking a vision test or providing a certificate stating that they can see well enough to drive. In an effort to minimize traffic through licensing offices, some states allow drivers to mail a renewal application along with a vision certificate and a check.

There is general acceptance of the need to require older drivers, at some point, to demonstrate that they really can drive safely, although acceptance by many of the older drivers themselves is more in principle than in personal practice ("I've been driving 50 years without a ticket; why should I have to prove I can still drive?"). The real issue is: When should older drivers have to take a test to show that they can still drive? In almost all states, there is an age at which drivers must begin appearing at a licensing office for a renewal examination. In many states, the interval between tests becomes shorter with advancing years. Today, the schedule and nature of renewal testing vary considerably from one state to another.

Setting an age and schedule for renewal testing is complicated by the vast differences among drivers in the rate of aging. The overwhelming majority of older drivers fall in the normal range in most abilities, and they also avoid having reportable accidents. However, low correlations across an entire population can conceal high levels of risk at the extremes. Drivers with severe deficits in a particular capability may show accident rates several times those of drivers in the normal range, just as heavy smokers have a greatly increased likelihood of cancer despite very low correlations between the two over the population. Requiring everybody to report for testing that will identify a small number of incompetents is not only expensive but imposes a needless and objectionable burden on the competent majority. And as that elderly majority makes up an increasing proportion of the body politic, the objections grow louder.

What is needed is better information on the proportion of drivers at each age who show unacceptable levels of decline and accident risk, with an eye to being able to specify an age when the declines and risk justify requiring some demonstration of ability. Actually, the marked differences in physical and mental abilities among older drivers offer a possible means of escaping the apparent dilemma of having to test large numbers with minimum inconvenience and cost. The means would be a relatively short screening test that can be given quickly, in a few minutes, yet is capable of spotting problems severe enough to affect driving skills. The few people who fail the screening test would be given more intensive testing to measure the precise nature and degree of their shortcomings.

The Maryland Motor Vehicle Administration is evaluating such a screening program, which ultimately might be integrated into a license renewal system. The screening process takes less than 15 minutes and includes tests for visual acuity, scanning, visualization of spatial relationships, and visual search and sequencing, as well as tests of memory and limb and head/neck mobility. Individuals who fail the screening are then subjected to a more detailed battery of tests. This program, still in an experimental stage, bears watching as an approach to identifying people at risk without unaffordable expense to licensing and unacceptable inconvenience to drivers.

Reports to licensing agencies. An alternative route for identifying at-risk older drivers is a referral process by which anyone having reason to believe a person is incapable of driving safely can report that driver to license authorities. Such reports can be tendered by police, relatives and neighbors of the driver, medical practitioners, or licensing personnel themselves. States vary greatly in the proportion of drivers reported and the sources of reports within states. The variation seems more readily attributed to differences in reporting practices than to differences in the characteristics of the drivers, which suggests that large numbers of deficient drivers in many states are going unreported.

Two forms of policy could improve the rate of reporting. First, laws could be enacted mandating that anyone who has knowledge of driver inadequacies must share that knowledge with the local licensing agency. Physicians and other medical specialists who treat the elderly may play a particularly important role here. However, reports from these sources have been largely inhibited by the privacy of the physician-patient relationship and the fear that many physicians have of being sued by patients who lose their licenses. Mandating reports circumvents that barrier. When Pennsylvania enacted legislation in 1994 requiring physicians to report, making them liable for damages resulting from failure to do so, the number of reports rose to 40,000 in the first year and has been increasing at a rate of about 4,000 per year since. Mandated reporting also could be extended to police when accidents or other incidents raise suspicion about a driver's abilities. Without such a requirement, many officers often are reluctant to take time away from other enforcement obligations to initiate the reporting process.

A less demanding form of policy would offer confidentiality and possible anonymity to any person who submits a report on a potentially high-risk driver. Extending such assurances is likely to facilitate reporting by family members and others who must continue to associate with the person being reported. Wherever reports are mandated, confidentiality needs to be a part of the mandate. Many licensing agencies currently are prevented from protecting those reporting by the rights of people to know their accusers. In some jurisdictions, it will take legislation to provide sufficient guarantees of confidentiality.

Voluntary assessment. A number of organizations provide resources through which elderly drivers can assess their driving abilities without fear of having deficiencies affect the status of their licenses. Many programs also include instruction for people who are mentally and physically able to handle a car in traffic but whose driving skills can stand some brushing up. For example, the Traffic Improvement Association of Michigan runs an eight-hour program that includes classroom instruction, various test measures, and a road test. Although open to anyone over age 55, two-thirds of the program's clients are at least 75 years old. In Florida, the St. Petersburg Area Agency on Aging runs a voluntary program for evaluating a wide range of driving skills. The program includes a road test that focuses on the aspects of driving most vulnerable to age-related decline. Although program officials report that the participation of most clients seems to be driven by the desire to prove their ability to themselves and their families, the results often lead to a decline or cessation of driving.

Determining risks

There is not much question about the importance of seeing clearly, knowing safe driving laws and practices, and being able to handle a car. Indeed, these are the primary factors now assessed in tests required to obtain and retain a driver license. But at a time of life when some of the fundamental physical and mental abilities required in driving may be in a state of decline, the scope of testing must be broadened if critical deficiencies are to be detected. The problem is, we do not know precisely which declines contribute directly to an elderly person's increased risk of becoming involved in a serious accident. Research has indicated that a host of abilities, including vision, attention span, memory, and reaction times, decline with age. These age-related declines, in turn, appear to be accompanied by a greater incidence of serious accidents. However, science cannot yet distinguish abilities whose decline actually contributes to bad driving from declines that just accompany bad driving. By analogy, the fact that poor algebra grades are associated with accidents among teenagers does not mean that poor grades cause accidents or that improving the grades will reduce accidents.

To better understand and ameliorate these cause-and-effect relationships, coordinated research efforts are needed. Prospective targets for such research include conducting in-depth accident investigations and using computer technologies such as virtual highways for testing the performance of elderly drivers.

We must make alternative forms of transportation more suitable to the elderly.

Accident investigations. The accidents of older drivers differ from those of other age groups. For example, twice as many accidents involving the elderly occur at intersections. Their forms of error can be revealed only through comprehensive investigations of accidents in which the older driver is culpable. But in-depth investigations are costly, in part because teams of investigators must be ready to respond the moment an accident involving an older driver is reported. Few of today's individual research projects have the funds required for such detailed investigations. Solving this problem will require the coordination of efforts and funding at the federal level between the agencies responsible for traffic safety and those concerned with problems of aging--coordination that has thus far been largely absent.

Applying technology. Computerized interactive simulation will soon allow more valid testing of overall driving ability than can be achieved in a car. It will thus be possible to confront older drivers with a wide array of traffic conditions tailored to the detection of specific deficits, and to do so without any risk to the driver. Today, limitations in computing power prevent the complexities of traffic from being simulated with enough fidelity to provide a valid test of driving. But given the rate at which computer technology is advancing, these limitations will soon be overcome and at an affordable cost.

Developing alternatives to driving

Probably the most daunting issue facing the transportation community is finding ways to meet the travel needs of people for whom the car is no longer available as the primary mode of transportation. This population includes people who choose to curtail their driving; those whose licenses are restricted in some way; and those who, by choice or requirement, no longer drive at all. Today, public transportation is structured primarily to accommodate suburban commuters, and foot travel is often precluded by the distances involved and the absence of pedestrian facilities along many streets. Other obstacles to use of public transit include unfamiliarity with routes and schedules, remoteness of stops, exposure to weather, need for assistance, and fear of harm. Adult children who may have served as a resource in years past are now less likely to live close by and usually have less time available to help their parents cope with everyday transportation needs.

Solving this problem will take efforts along several lines. First, we must develop ways to assist the elderly in making better use of alternative means of transportation already available. Second, we must make alternative forms of transportation more suitable to the elderly. Underlying both of these issues is the need to elevate transportation among the concerns that establish priorities in meeting the requirements of the elderly.

Assisting the elderly. Many communities supplement their public transit systems by supporting "paratransit" operations that provide the elderly with scheduled pickup and delivery service to popular destinations, such as medical facilities, senior centers, recreation facilities, and shopping malls. In some communities, private organizations also supply volunteers to take elderly citizens anywhere they want to go. However, few communities have a formal system for helping their elderly make the transition from the car to alternative sources of transportation, leaving many people unaware of the services that are available. Here is where local organizations that provide various types of assistance to the elderly can help, by supplying information on public and alternative transit systems, what they provide, destinations and schedules, and how to gain access. For example, a local agency in Michigan, recognizing the hesitance of some elderly people to face the unfamiliar alone, provides volunteers (usually age peers) to accompany seniors on their first trips using alternative transportation.

Licensing agencies also may play an important role. The time when an older driver has become the subject of license action is certainly ripe for initiating a transition process from cars to alternative transportation. People who could benefit from such help are not just those whose licenses are being withdrawn or restricted by the agency, but also the no-shows who give up their license when called in for reexamination or when their license is up for renewal. Today, however, licensing agencies make little or no effort to help drivers initiate a shift to public transportation. Oregon stands as an exception. There, elderly drivers called in for examination because of some incident are given individual counseling, during which they receive information on public transportation and on other community services that are available to help them make the transition away from their cars.

Improving alternative transportation. To a great extent, attempts to meet the transportation needs of the elderly have adopted a supply-side orientation: that is, a focus on encouraging greater use of existing resources rather than adapting systems to the needs of the elderly. However, a growing number of communities is beginning to expand the options available to the elderly by coordinating the operations of various providers, thus furnishing a more responsive service while keeping costs low. Such coordination has been orchestrated at the state level in Florida and Pennsylvania.

The past several years also have seen the growth of even more flexible transportation systems, designed to provide anywhere, anytime service. One such system operates in the city of Portland, Maine. To achieve responsiveness at affordable cost, this system uses timely scheduling and automated routing to permit destinations to be linked and rides to be shared, as well as volunteers to augment paid drivers. To supplement its public funding, the system solicits donations from family members, local businesses, and community organizations that stand to benefit from the service provided. The state of Pennsylvania operates a "Shared-Ride" program, available in all 67 counties, that provides local door-to-door transportation services. The system provides 6.5 million reduced-fare trips annually. As yet, neither of these systems is close to being self-supporting. The program in Maine has been subsidized heavily by federal and state grants, while the Pennsylvania program gets 85 percent of its funds from the proceeds of the state lottery.

A single service capable of providing transportation to many destinations can create an identity that, in turn, can create a community of users willing to accept the ride sharing needed to make the service economically sustainable. However, the likely need for at least some outside funds, coupled with the fact that such services are often in competition with other public and private transportation systems (including taxis) for patronage, can make their operation an issue of local transportation policy. Nevertheless, the individualized transportation that such systems provide makes this form of service one of the more innovative and promising approaches to satisfying the travel needs of the elderly.

Boosting priority in public policy. The transportation needs of the elderly have not been high on the public policy agenda at any level: national, state, or local. Rather, this issue typically lags far behind other issues thought to more directly affect the public at large. Generally speaking, legislation is driven more by events than statistics. Unfortunately, most incidents involving elderly drivers--serious crashes--draw more attention to their failings than to their needs. But like the proverbial silver lining, such incidents may trigger action within the affected population that results in the development of coalitions that can drive long-term efforts to gain enactment of legislation designed to help rather than restrict the elderly.

A good example of what's possible is the early drunk-driving legislation formulated and advanced by coalitions created largely by women whose children were killed by drunk drivers. Although such groups focused much of their early activities primarily on punishing the drivers, they have since achieved greater success by expanding their efforts to address the drinking that gives rise to incidents. In the same way, interest aroused by an accident involving an older driver might be exploited to advance legislation that addresses the broad transportation needs of the elderly. To date, successful efforts at the state and local levels to improve transportation for the elderly have been built on cooperation among agencies concerned with aging, transportation, social services (including Medicare), disability, health, and mental health. Most of these efforts have focused on providing transportation to all types of underserved populations, not just the elderly. However, the growth in the numbers of elderly over the next decades will bring both increased political power to push for better transportation resources and increased demand on those resources. The time to prepare for both is obviously now.

Recommended reading

Jon E. Burkhardt, Coordinated Transportation Systems (Washington, D.C.: American Association of Retired Persons, report number 2000-16, September 2000).

Liisa Hakamies-Blomqvist, "Older Road Users," Accident Analysis and Prevention 30, no. 3 (1998).

Transportation in an Aging Society: A Decade of Experience (Washington, D.C.: Transportation Research Board, National Research Council, in press).


A. James McKnight (jimmcknight@earthlink.net) is president of Transportation Research Associates, Annapolis, Maryland.