Wouldn't it be great if there was a predictive screening process that helped identify people whose driving problems would be likely to cause future accidents and other mishaps? As the numbers of older drivers soars, so will the need for fair ways to evaluate their skills. It's possible that pressures for wholesale restrictions on older drivers will grow as well, spurred by the inevitable tragic accidents involving old drivers who clearly didn't belong behind the wheel. Well, as it turns out, if you want a solid solution to this problem, you can find one in Maryland, whose Motor Vehicle Administration (MVA) began developing predictive screening tools a decade ago. It even validated its approach with a comprehensive research project whose results were published in 2006. Why haven't other states rushed to emulate Maryland? Good question. Complicated answer.
[See Are Seniors Being Targeted as Bad Drivers?]
There are many different state approaches to licensing and safety for older drivers. Trying to create a one-size fits all solution is not feasible. The AAA Foundation has a helpful tool that illustrates differences among the states. Use it to understand your own state's rules.
Carl Soderstrom, a physician, is chief of the MVA's Medical Advisory Board (MAB), which processes thousands of driver complaints and referrals each year and flows them into an evaluation process that, ultimately, can either reaffirm, restrict or remove an individual's driving rights. Soderstrom says Maryland's 60-year-old MAB is the nation's oldest, and it's clear that having a medical review and referral system in place, along with a mature infrastructure of clinical and therapeutic expertise, is essential to a successful driving review process.
After offering what he calls its functional capacity screening for several years, Soderstrom explained, the state engaged researchers to review results of the screening, including subsequent driving histories extending several years into the future. Led by psychologist Dr. Karlene K. Ball, an aging expert and professor at the University of Alabama at Birmingham, the cases of nearly 2,000 screened Maryland drivers were reviewed. The research found that people scoring poorly on the screening were, roughly speaking, twice as likely to be involved in at-fault crashes as people who did better on the procedures. According to the findings, published in a 2006 article in the Journal of The American Geriatrics Society, "performance-based cognitive measures are predictive of future at-fault" collisions, and "high-risk older drivers can be identified through brief, performance-based measures administered in a MVA setting."
Perhaps surprisingly, the researchers said, "there have been no large-scale, prospective studies wherein a wide range of performance-based risk factors for crash involvement have been objectively evaluated." Vision tests, they said, are not consistently related to subsequent driving performance. And Soderstrom noted that many impaired older drivers can still ace a standard driving test. "It's like learning to ride a bike," he explains. "There are some things you just never forget." But putting drivers in the real driving world might produce far different results, and Maryland's screening efforts help predict real-world outcomes.
The state's screening includes several computer-based tests and one physical requirement, in which a person is asked to walk quickly, up and back, along a 10-foot line marked on the floor (a time of 7-8 seconds is considered acceptable). Soderstrom notes that the computer test takes 10-15 minutes, and stresses that the test involves touch-screen prompts and thus doesn't require the person to be a regular computer user. Here are the computer elements of Maryand's screening process:
- Pelli-Robson Visual Contrast Sensitivity Test. While the traditional acuity test measures how well one can see detail that stands out in sharp contrast to its background—like letters on a street sign—this test is more concerned with poorly defined shapes and edges that look much like their surroundings.
- Cued Recall (working memory). The client is given the names of three objects (such as “bed, apple, shoe”) to remember, which they are asked to repeat back to examiner. Several minutes later they are again asked to recall and name the three objects. Two wrong responses raise concern.
- Motor Free Visual Perception Test (MVPT). This test requires that the subject “fill in” the missing information when only part of it is presented. The MVPT assesses the ability to identify different kinds of potential threats and critical safety information as one is driving. The subject is presented with a complete diagram and asked to identify which of a number of presented incomplete diagrams, if completed, would correspond to the one presented. Eleven diagrams are presented. A score of four or more wrong is of concern.
- Trails B Test. This test assesses working memory, visual processing, visual-spatial skills, and divided attention. The subject is presented with the numbers 1 to 13 and the letters A to L randomly placed on a sheet of paper. Each number and letter is circled. The subject is asked to draw a line from “1” to “A,” then “A” to “2,” then “2” to “B,” and so on. A score of over 150 seconds (2½ minutes) raises concern.
- Useful Field of View. This test assesses the ability to pay attention to what is directly in front of an individual, while at the same time asking him to perceive peripheral threats. While focusing on a central object on a video screen, images of a car or truck are flashed at peripheral points on the screen. The subject is asked to touch the screen where the peripheral image appeared. As the test progresses, the peripheral images are presented for shorter and shorter durations of time.
[See also Take a Road Test of Your Driving Skills.]
Soderstrom says Maryland's screening process is designed to help keep drivers on the road, not to take away their licenses. By accurately identifying at-risk drivers, he explains, the state can provide training and other assistance to help people keep driving. For example, he says, older drivers may receive home visits byMVA professionals to determine their practical driving needs—neighborhood errands, doctors visits and the like. If a driver navigates those local trips, Soderstrom says, the agency may issue a restricted license that permits local driving but not highway or night-time driving. Still, the approach can only screen drivers referred to the MAB and no one knows what percentage of at-risk drivers is referred each year in Maryland. Most likely, it's a small number.
Maryland screens drivers because there is some question about their skills, not because they have reached a certain age. Such "age-blind" policies are supported byAARP and other seniors' groups concerned about blanket restrictions being unfairly placed on the driving of all seniors because of a few tragic accidents by a handful of older drivers. According to a 2007 Rand Institute report, “Drivers 65 and older are 16 percent likelier than adult drivers [age 25-64] to cause an accident. Young drivers [age 15-24] are 188 percent likelier than adult drivers to cause an accident. The older individuals who drive are not much more dangerous than middle-aged [adults age 25-64] drivers."
Whether Maryland's approach spreads to other states or not, there is no escaping the coming surge in older drivers and the need to develop better oversight systems to monitor their performance on the roads. "This need is not going away," Soderstrom says. "This is only going to become a more and more prevalent issue."