Family reports of medically impaired drivers in Missouri: Cognitive concerns and licensing outcomes

This study investigated reasons why older adults (n = 689) were reported to the Driver License Bureau, Missouri Department of Revenue, by family members as potentially unfit to drive with an emphasis on cognitive concerns and associated licensing outcomes. A total of 448 drivers were reported to have some cognitive issue; common symptoms included confusion, memory loss, and becoming lost while driving. Diagnostic labels (Alzheimer’s disease (AD), cognitive impairment/dementia, brain injury/insult) were listed for 365 cases. A physician evaluation is required for license review. Of those with a diagnostic label, half (51%, n = 187) failed to submit this evaluation and almost all were de-licensed immediately. Of those evaluated by a physician, diagnostic agreement between family members and physicians was high for specific conditions (100% for AD, 97% for acute brain injury), and less so for cognitive impairment/dementia (75%). This latter finding suggests that physicians and family members may understand cognitive symptoms differently. Whether cognitively impaired or not, few family reported drivers in this sample (∼2%) retained a valid license. Family members may be in the best position to recognize when medical-functional deficits impact on driving safety, and physicians and driver licensing authorities would do well to take their observations into account with respect to older driver fitness.     

The Maze Test: A significant predictor of older driver crash risk

A study sponsored by the National Highway Traffic Safety Administration performed functional assessments on approximately 700 drivers age 70 and older who presented for license renewal in urban, suburban, and rural offices of the Maryland Motor Vehicle Administration. This volunteer sample received a small compensation for study participation, with an assurance that their license status would not be affected by the results. A comparison with all older drivers who visited the same sites on the same days indicated that the study sample was representative of Maryland older drivers with respect to age and prior driving safety indices. Relationships between drivers’ scores on a computer touchscreen version of the Maze Test and prospective crash and serious moving violation experience were analyzed. Results identified specific mazes as highly significant predictors of future safety risk for older drivers, with a particular focus on non-intersection crashes. Study findings indicate that performance on Maze Tests was predictive of prospective crashes and may be useful, as a complement to other, established cognitive screening tools, in identifying at-risk older drivers.     

Findings from the Candrive/Ozcandrive study: Low mileage older drivers,crash risk and reduced fitness to drive

Previous research has found that only older drivers with low annual driving mileages had a heightened crash risk relative to other age groups. These drivers tend to drive mainly in urban areas, where the prevalence of complex traffic situations increases crash risk. However it might also be that some drivers may have reduced their driving due to perceived or actual declines in driving fitness.     

Evaluating the crash and citation rates of Utah drivers licensed with medical conditions, 1992-1996

BACKGROUND: Medical problems may affect the ability to drive motor vehicles, and programs that control the issuing of driver licenses to individuals with medical conditions exist in most states. The main activity of these programs is the imposition of restrictions upon the driving privileges of individuals with medical conditions that are deemed to pose some risk to public safety. However, little is known about the effectiveness of these licensing programs. OBJECTIVE: The objective of this study was to compare the rates of adverse driving events (crash, at-fault crash and citations) experienced by drivers licensed with medical conditions to those of age-, sex- and location-matched controls. Separate comparisons were made for drivers reporting medical conditions licensed with full driving privileges, and those with restricted driving privileges (e.g. speed, area and time of day). DESIGN: Retrospective case-control. METHODS: The study population was all drivers licensed in the state of Utah who reported a medical condition on their driver license application, over the 5-year period 1992-1996. Drivers enter the program by self-reporting their medical problems. Control drivers were chosen from the entire population of drivers licensed in Utah for the same period. Information on driver license status, participation in the medical conditions program, citations, involvement in crashes, and death certificate data was obtained from the relevant state agencies. Probabilistic linkage methodology was used to link the records in these disparate databases for eventual analysis. Rates of citation, crashes and at-fault crashes, expressed as events per 10000 license days, were calculated separately for program drivers and their corresponding control groups for each medical condition category and restriction status. These data were used to determine an estimate of relative risk (RR) and 95% confidence intervals. Results: As a group, medical conditions drivers had modestly elevated rates of adverse driving events compared with control drivers (RR 1.09-1.74). Rates in the largest medical category, 'cardiovascular conditions', were not higher than controls. Rates were higher than control for some conditions, such as 'alcohol' and 'learning and memory', for some adverse events (RR 2.2 -5.75). Drivers with more than one medical condition appeared comparable to the general group of medical conditions program drivers. CONCLUSIONS: Drivers in Utah medical conditions program had modestly elevated rates of adverse driving events compared to matched controls. Possible underreporting of medical conditions and accurate assessment of exposure rates are potential weaknesses in the program.     

Declines in fatal crashes of older drivers: changes in crash risk and survivability

Objectives

Previous research has found that older driver fatal crash involvement rates per licensed driver declined substantially in the United States during 1997–2006 and declined much faster than the rate for middle-age drivers. The current study examined whether the larger-than-expected decline for older drivers extended to nonfatal crashes and whether the decline in fatal crash risk reflects lower likelihood of crashing or an improvement in survivability of the crashes that occur.

Methods

Trends in the rates of passenger vehicle crash involvements per 100,000 licensed drivers for drivers 70 and older (older drivers) were compared with trends for drivers ages 35–54 (middle-age drivers). Fatal crash information was obtained from the Fatality Analysis Reporting System for years 1997–2008, and nonfatal crash information was obtained from 13 states with good reporting information for years 1997–2005. Analysis of covariance models compared trends in annual crash rates for older drivers relative to rates for middle-age drivers. Differences in crash survivability were measured in terms of the odds of fatality given a crash each year, and the historical trends for older versus middle-age drivers were compared.

Results

Fatal crash involvement rates declined for older and middle-age drivers during 1997–2008 (1997–2005 for the 13 state subsample), but the decline for drivers 70 and older far exceeded the decline for drivers ages 35–54 (37 versus 23 percent, nationally; 22 versus 1 percent, 13 states). Nonfatal injury crash involvement rates showed similarly larger-than-expected declines for older drivers in the 13 state subsample, but the differences were smaller and not statistically significant (27 percent reduction for older drivers versus 16 percent for middle-age drivers). Property-damage-only crash involvement rates declined for older drivers (10 percent) but increased for middle-age drivers (1 percent). In 1997, older drivers were 3.5 times more likely than middle-age drivers to die in police-reported crashes (6.2 versus 1.8 deaths per 1000 crashes), but this difference was reduced during the 9-year study period to 2.9 times, as the rate of older drivers dying in a crash declined (5.5 deaths per 1000 crashes in 2005) and the death risk remained relatively stable for middle-age drivers.

Conclusions

Contrary to expectations based on increased licensure and travel by older drivers, their fatal crash risk has declined during the past decade and has declined at a faster rate than for middle-age drivers. The decreased risk for older drivers appears to extend not only to nonfatal injury crashes but also to property-damage-only crashes, at least as reported to police in the 13 states included in the nonfatal injury analysis. Although insurance collision data suggest that overall crash risk of older drivers may not be changing relative to middle-age drivers, the current analysis indicates that the reduced fatality risk of older drivers reflects both less likelihood of being involved in a police-reported crash and greater likelihood that they will survive when they do crash.     

The licensing and safety of older drivers in Britain

Driving licence holding in Britain is increasing for older people, particularly older women. Licence holding by men aged 40–69 has saturated at about 90%, and for women aged 30–59 at about 78%. Drivers begin to surrender licences after age 70. By age 90, 38% of women and 25% of men who held a licence at age 70 have surrendered their licences.     

The Addenbrooke's Cognitive Examination Revised as a potential screening test for elderly drivers

Considerable research has shown that neuropsychological tests are predictive of real-world driving ability. The Mini-Mental State Examination (MMSE) is a brief cognitive test that has been commonly used in the assessment of older drivers. However, this test has inherent problems that limit its validity to evaluate cognitive abilities related to driving and to screen for driving impairments in non-demented people. Therefore, it is useful to test new screening instruments that may predict potential unsafe drivers who require an in-depth neuropsychological assessment in a specialised centre. To date, the utility of the Addenbrooke's Cognitive Examination Revised (ACE-R) as an indicator of driving ability has not been established. In the current study, fifty older drivers (mean age = 73.1 years) who were referred for a psychological assessment, the protocol of which included the ACE-R, underwent an on-road driving test. Using linear discriminant analyses, the results highlighted the higher classification accuracy of the ACE-R compared to the MMSE score, particularly for detecting unsafe drivers. Measures of visuospatial and executive functions, which are not incorporated in the MMSE score, had an incremental value in the prediction of driving ability. This emerging brief cognitive test may warrant additional study for use in the fitness to drive assessment of older adults.     

Physician input and licensing of at-risk drivers: A review of all-inclusive medical evaluation forms in the US and Canada

This article details a systematic review of medical evaluation forms in support of licensing decisions for medically at-risk drivers. Comparisons were made between all-inclusive forms utilized by 52 State and Provincial Departments of Motor Vehicles (DMVs) in the US and Canada. Comparisons focused on length, format, content, instructional quality, medical coverage, ease of use, and other qualitative characteristics. Median page length was 2 (range 1–10), and mean word count was 1083 (494–3884). Common response options included open-ended (98%), forced choice (87%), and check box (81%). While the majority of forms (77%) required driver consent, only 24% requested information from the driver. Less than half (46%) included text on confidentiality protection. While all forms requested general medical information, just over half included specific sections for vision (54%) and cognitive/neurological conditions (56%). Most forms (81%) required that a judgment be made concerning driver safety, and half prompted for possible license restrictions. Criterion-based quality ratings were assigned on a five-point Likert scale by group consensus. One third of forms were rated as marginal or poor in comprehensiveness and utility, and just two garnered an excellent overall rating. Findings are discussed relative to current research on driver fitness and elements of a proposed model form. Best practice recommendations include a page length limitation, emphasis on in-person evaluation (i.e., as opposed to a records-only review), prompts to collect crash and other driving history information, clear instructions and stepwise format, content prompts across relevant medical categories, documentation of functional status and impairment levels, options for driving with restrictions in lieu of de-licensing, and emphasis on relative (vs. absolute) clinical judgments of overall driver safety.