To determine the validity and reliability of clinician ratings of the driving competence of patients with mild dementia.
Observational study of a cross-section of drivers with mild dementia based on chart review by clinicians with varying types of expertise and experience.
Outpatient dementia clinic.
Fifty dementia subjects from a longitudinal study of driving and dementia.
Each clinician reviewed information from the clinic charts and the first study visit. The clinician then rated the drivers as safe, marginal, or unsafe. A professional driving instructor compared these ratings with total driving scores on a standardized road test and categorical ratings of driving competence. Clinicians also completed a visual analog scale assessment of variables that led to their determinations of driving competence.
Accuracy of clinician ratings ranged from 62% to 78% for the instructor’s global rating of safe versus marginal or unsafe. In general, there was moderate accuracy and interrater reliability. Accuracy could have been improved in the least-accurate raters by greater attention to dementia duration and severity ratings, as well as less reliance on the history and physical examination. The most accurate predictors were clinicians specially trained in dementia assessment, who were not necessarily the most experienced in their years of clinical experience.
Although a clinician may be able to identify many potentially hazardous drivers, accuracy is insufficient to suggest that a clinician’s assessment alone is adequate to determine driving competence in those with mild dementia.
dementia; driving; Alzheimer’s disease
This study assessed the clinical utility of contrast sensitivity (CS) relative to attention, executive function, and visuospatial abilities for predicting driving safety in participants with Parkinson's disease (PD). Twenty-five, non-demented PD patients completed measures of contrast sensitivity, visuospatial skills, executive functions, and attention. All PD participants also underwent a formal on-road driving evaluation. Of the 25 participants, 11 received a marginal or unsafe rating on the road test. Poorer driving performance was associated with worse performance on measures of CS, visuospatial constructions, set shifting, and attention. While impaired driving was associated with a range of cognitive and visual abilities, only a composite measure of executive functioning and visuospatial abilities, and not CS or attentional skills, predicted driving performance. These findings suggest that neuropsychological tests, which are multifactorial in nature and require visual perception and visual spatial judgments are the most useful screening measures for hazardous driving in PD patients.
Contrast sensitivity; Executive function; Visuospatial; Activities of daily living
A large number of licensed elderly drivers are demented or are likely to become demented. On-road driving tests, a method often used to assess driver competency, are likely anxiety-provoking for elderly individuals. This article examines the relationship between anxiety and driving performance in a mildly demented and elderly control (EC) sample.
Anxiety ratings of fear and tension, as assessed by visual analog scales, of 84 patients clinically diagnosed with mild Alzheimer’s disease (AD) (68 safe/marginal and 16 unsafe drivers) were compared with those of 44 age- and education-equated safe/marginal EC participants, both before and after a standardized on-road driving test.
Analyses revealed significant positive correlations between AD patients’ pre–road test and post–road test tension and post–road test fear ratings and total road test score. Subsequent analyses of variance showed no significant pre–road test differences in fear ratings between the three groups but significantly higher levels of tension among the unsafe AD participants. After adjusting for baseline group differences, unsafe AD drivers experienced stable or higher anxiety levels after road test, whereas both the EC and safe/marginal AD drivers endorsed a significant reduction in anxiety.
Unlike their safe EC and safe AD driver counterparts, unsafe AD patients reported continued elevated levels of fear and tension after the road test. Given these findings, we suggest that the most appropriate time for driving instructors to counsel patients regarding their driving skills might be directly after the road test.
Alzheimer’s disease; Driving; Road test; Anxiety; Visual analog mood scales
Physicians and family members frequently are asked to provide information about driving ability in patients with Alzheimer’s disease (AD), yet there has been little research on the validity of their assessments of driving performance.
Participants were recruited from the neurology department of a community hospital affiliated with Brown Medical School.
Participants included 75 older adults (17 with mild AD, 33 with very mild AD, and 25 elderly controls).
The participant him/herself, an informant, and an experienced neurologist rated each participant’s driving ability on a 3-point rating scale (safe, marginal, unsafe). A professional driving instructor also completed a standardized 108-point on-road driving assessment of each participant and then rated driving ability on the 3-point scale. Ratings were compared with the on-road driving score and with each other.
Only the neurologist’s rating of the participants’ driving abilities was significantly related to on-road driving score. When related to the instructor’s safety rating, the neurologist’s ratings were the most sensitive and specific. Mini-Mental State Examination score was a borderline covariate for the neurologist’s rating. Overall, the instructor was the most stringent rater of participant driving ability, followed by the neurologist, the informant, and the participant.
An experienced neurologist’s assessment of driving competence may be a valid predictor of driving performance of patients with early AD.
dementia; driving; assessment; Alzheimer’s disease
Neuropsychological and motor deficits in Parkinson’s disease that may contribute to driving impairment were examined in a cohort study comparing patients with Parkinson’s disease (PD) to patients with Alzheimer’s disease (AD) and to healthy elderly controls. Nondemented individuals with Parkinson’s disease [Hoehn & Yahr (H&Y) stage I–III], patients with Alzheimer’s disease [Clinical Demetia Rating scale (CDR) range 0–1], and elderly controls, who were actively driving, completed a neuropsychological battery and a standardized road test administered by a professional driving instructor. On-road driving ability was rated on number of driving errors and a global rating of safe, marginal, or unsafe. Overall, Alzheimer’s patients were more impaired drivers than Parkinson’s patients. Parkinson’s patients distinguished themselves from other drivers by a head-turning deficiency. Drivers with neuropsychological impairment were more likely to be unsafe drivers in both disease groups compared to controls. Compared to controls, unsafe drivers with Alzheimer’s disease were impaired across all neuropsychological measures except finger tapping. Driving performance in Parkinson’s patients was related to disease severity (H&Y), neuropsychological measures [Rey Osterreith Complex Figure (ROCF), Trails B, Hopkins Verbal List Learning Test (HVLT)-delay], and specific motor symptoms (axial rigidity, postural instability), but not to the Unified Parkinson Disease Rating Scale (UPDRS) motor score. Multifactorial measures (ROCF, Trails B) were useful in distinguishing safe from unsafe drivers in both patient groups.
Dementia; Motor vehicles; Cognition; Memory; Neurodegenerative diseases; Basal ganglia
This study examined the ability of computerized maze test performance to predict the road test performance of cognitively impaired and normal older drivers. The authors examined 133 older drivers, including 65 with probable Alzheimer disease, 23 with possible Alzheimer disease, and 45 control subjects without cognitive impairment. Subjects completed 5 computerized maze tasks employing a touch screen and pointer as well as a battery of standard neuropsychological tests. Parameters measured for mazes included errors, planning time, drawing time, and total time. Within 2 weeks, subjects were examined by a professional driving instructor on a standardized road test modeled after the Washington University Road Test. Road test total score was significantly correlated with total time across the 5 mazes. This maze score was significant for both Alzheimer disease subjects and control subjects. One maze in particular, requiring less than 2 minutes to complete, was highly correlated with driving performance. For the standard neuropsychological tests, highest correlations were seen with Trail Making A (TrailsA) and the Hopkins Verbal Learning Tests Trial 1 (HVLT1). Multiple regression models for road test score using stepwise subtraction of maze and neuropsychological test variables revealed significant independent contributions for total maze time, HVLT1, and TrailsA for the entire group; total maze time and HVLT1 for Alzheimer disease subjects; and TrailsA for normal subjects. As a visual analog of driving, a brief computerized test of maze navigation time compares well to standard neuropsychological tests of psychomotor speed, scanning, attention, and working memory as a predictor of driving performance by persons with early Alzheimer disease and normal elders. Measurement of maze task performance appears to be useful in the assessment of older drivers at risk for hazardous driving.
driving; dementia; mild cognitive impairment; maze; computerized assessment
The objective was to compare a standardized road test to naturalistic driving by older people who may have cognitive impairment to define improvements that could potentially enhance the validity of road testing in this population.
Road testing has been widely adapted as a tool to assess driving competence of older people who may be at risk for unsafe driving because of dementia; however, the validity of this approach has not been rigorously evaluated.
For 2 weeks, 80 older drivers (38 healthy elders and 42 with cognitive impairment) who passed a standardized road test were video recorded in their own vehicles. Using a standardized rating scale, 4 hr of video was rated by a driving instructor. The authors examine weighting of individual road test items to form global impressions and to compare road test and naturalistic driving using factor analyses of these two assessments.
The road test score was unidimensional, reflecting a major factor related to awareness of signage and traffic behavior. Naturalistic driving reflected two factors related to lane keeping as well as traffic behavior.
Maintenance of proper lane is an important dimension of driving safety that appears to be relatively underemphasized during the highly supervised procedures of the standardized road test.
Road testing in this population could be improved by standardized designs that emphasize lane keeping and that include self-directed driving. Additional information should be sought from observers in the community as well as crash evidence when advising older drivers who may be cognitively impaired.
driving; aging; dementia; Alzheimer’s disease; cognitive impairment
The goal of this study was to define the natural progression of driving impairment in persons who initially have very mild to mild dementia.
We studied 128 older drivers, including 84 with early Alzheimer’s disease (AD) and 44 age-matched control subjects without cognitive impairment. Subjects underwent repeated assessments of their cognitive, neurological, visual and physical function over three years. Self-reports of driving accidents and traffic violations were supplemented by reports from family informants and state records. Within two weeks of the office evaluation, subjects were examined by a professional driving instructor on a standardized road test.
At baseline, AD subjects had experienced more accidents and performed more poorly on the road test, compared to controls. Over time, both groups declined in driving performance on the road test, with AD subjects declining more than controls. Survival analysis indicated that while the majority of subjects with AD passed the examination at baseline, greater severity of dementia, increased age, and lower education were associated with higher rates of failure and marginal performance.
This study confirms previous reports of potentially hazardous driving in persons with early AD, but also indicates that some individuals with very mild dementia can continue to drive safely for extended periods of time. Regular followup assessments, however, are warranted in those individuals.
To develop a cognitive and functional screening battery for the on-road performance of older drivers with dementia.
A prospective observational study.
On-road driving evaluation clinic at an academic rehabilitation center
Ninety-nine older people with dementia (63% male, mean age = 74.2 years, SD= 9), referred by community physicians to an Occupational Therapy driving clinic.
The outcome variable was pass/fail on the modified Washington University Road Test. Predictor measures were tests of visual, motor and cognitive functioning, selected for their empirical or conceptual relationship to the complex task of driving safely.
Sixty-five (65%) of participants failed the on-road driving test. The best predictive model, with an overall accuracy of up to 85% when participants were blinded, included AD-8 score, the Clock Drawing Test score, and the time to complete either the Snellgrove Maze Test (SMT) or Trail Making Test A. Visual and motor functioning were not associated with road driving test failure.
A screening battery that could be performed in less than 10 minutes predicted with good accuracy a failure rating on the on-road driving test in this sample of older drivers with dementia. A “probability of failure” calculator is provided from a logistic regression model that may be useful for clinicians in their decision to refer impaired older adults for further testing. More studies are needed in larger community based samples, along with discussions with patients, families and clinicians, in regards to acceptable levels of test uncertainty.
on-road driving safety; dementia; older drivers
Neuropsychological tests are useful for diagnosing Alzheimer’s disease (AD), yet for many tests, diagnostic accuracy statistics are unavailable. We present diagnostic accuracy statistics for seven variables from the Neuropsychological Assessment Battery (NAB) that were administered to a large sample of elderly adults (n = 276) participating in a longitudinal research study at a national AD Center. Tests included Driving Scenes, Bill Payment, Daily Living Memory, Screening Visual Discrimination, Screening Design Construction, and Judgment. Clinical diagnosis was made independent of these tests, and for the current study, participants were categorized as AD (n = 65) or non-AD (n = 211). Receiver operating characteristics curve analysis was used to determine each test’s sensitivity and specificity at multiple cut points, which were subsequently used to calculate positive and negative predictive values at a variety of base rates. Of the tests analyzed, the Daily Living Memory test provided the greatest accuracy in the identification of AD and the two Screening measures required a significant tradeoff between sensitivity and specificity. Overall, the seven NAB subtests included in the current study are capable of excellent diagnostic accuracy, but appropriate understanding of the context in which the tests are used is crucial for minimizing errors.
The road test is regarded as the gold standard for determining driving competence in older adults, but it is unclear how well the road test relates to naturalistic driving. The study objective was to relate the standardized road test to video recordings of naturalistic driving in older adults with a range of cognitive impairment.
Cross-sectional observational study.
Academic medical center memory disorders clinic.
103 older drivers (44 healthy and 59 with cognitive impairment) who passed a road test.
Error rate and global ratings of safety (pass with and without recommendations, marginal with restrictions or training, or fail) made by a professional driving instructor.
There was fair agreement between global ratings on the road test and naturalistic driving. More errors were detected in the naturalistic environment, but this did not impact global ratings. Error scores between settings were significantly correlated, and the types of errors made were similar. History of crashes corrected for miles driven per week was related to road test error scores, but not naturalistic driving error scores. Global cognition (MMSE) was correlated with both road test and naturalistic driving errors. In the healthy older adults, younger age was correlated with fewer errors on the road test and greater errors in naturalistic driving.
Road test performance is a reasonable proxy for estimating fitness to drive in older individuals’ typical driving environments. The differences between performance assessed by these two methods, however, remain poorly understood and deserve further study.
driving; dementia; naturalistic; assessment
Objectives: The primary aim of this study was to determine how Parkinson's disease (PD) affects driving performance. It also examined whether changes in driver safety were related to specific clinical disease markers or an individual's self rating of driving ability.
Methods: The driving performance of 25 patients with idiopathic PD and 21 age matched controls was assessed on a standardised open road route by an occupational therapist and driving instructor, to provide overall safety ratings and specific driving error scores.
Results: The drivers with PD were rated as significantly less safe (p<0.05) than controls, and more than half of the drivers with PD would not have passed a state based driving test. The driver safety ratings were more strongly related to disease duration (r = –0.60) than to their on time Unified Parkinson's Disease Rating Scale (r = –0.24). Drivers with PD made significantly more errors than the control group during manoeuvres that involved changing lanes and lane keeping, monitoring their blind spot, reversing, car parking, and traffic light controlled intersections. The driving instructor also had to intervene to avoid an incident significantly more often for drivers with PD than for controls. Interestingly, driver safety ratings were unrelated to an individual's rating of their own driving performance, and this was the case for all participants.
Conclusions: As a group, drivers with PD are less safe to drive than age matched controls. Standard clinical markers cannot reliably predict driver safety. Further studies are required to ascertain whether the identified driving difficulties can be ameliorated.
Demographically-adjusted norms are used to enhance accuracy of inferences based on neuropsychological assessment. However, we hypothesized that predictive accuracy regarding complex real-world activities is diminished by demographic corrections. Driving performance was assessed with a standardized on-road test in participants aged 65+ (24 healthy elderly, 26 Alzheimer’s disease, 33 Parkinson’s disease). Neuropsychological measures included Trailmaking A and B, Complex Figure, Benton Visual Retention, and Block Design tests. A multiple regression model with raw neuropsychological scores was significantly predictive of driving errors (R2 = .199, p <.005); a model with demographically-adjusted scores was not (R2 = .113, p >.10). Raw scores were more highly correlated than adjusted scores with each neuropsychological measure, and among both healthy elderly and Parkinson’s patients. Demographic corrections diminished predictive accuracy for driving performance, extending findings of Silverberg and Millis (2009) that competency in complex real-world activities depends on ability levels, regardless of demographic considerations.
aged; age factors; automobile driving; geriatric assessment; Parkinson’s; Alzheimer disease
A battery of standard neuropsychological tests examining various features of executive function, attention, and visual perception was administered to 27 subjects with questionable to mild dementia and compared to a 4-point caregiver rating scale of driving ability. Based on the results of this study, a computerized maze task, employing 10 mazes, was administered to a second sample of 40 normal elders and questionable to moderately demented drivers. Comparison was made to the same caregiver rating scale as well as to crash frequency. In the first study of neuropsychological tests, errors on Porteus Mazes emerged as the only significant predictor of driving ability in a stepwise regression analysis. In the follow-up study employing the computerized mazes, all 10 mazes were significantly related to driving ability ratings. Computerized tests of maze performance offer promise as a screening tool to identify potential driving impairment among cognitively impaired elderly and demented drivers.
driving; dementia; Alzheimer’s disease; neuropsychology; cognition
Driving a car is a complex instrumental activity of daily living and driving performance is very sensitive to cognitive impairment. The assessment of driving-relevant cognition in older drivers is challenging and requires reliable and valid tests with good sensitivity and specificity to predict safe driving. Driving simulators can be used to test fitness to drive. Several studies have found strong correlation between driving simulator performance and on-the-road driving. However, access to driving simulators is restricted to specialists and simulators are too expensive, large, and complex to allow easy access to older drivers or physicians advising them. An easily accessible, Web-based, cognitive screening test could offer a solution to this problem. The World Wide Web allows easy dissemination of the test software and implementation of the scoring algorithm on a central server, allowing generation of a dynamically growing database with normative values and ensures that all users have access to the same up-to-date normative values.
In this pilot study, we present the novel Web-based Bern Cognitive Screening Test (wBCST) and investigate whether it can predict poor simulated driving performance in healthy and cognitive-impaired participants.
The wBCST performance and simulated driving performance have been analyzed in 26 healthy younger and 44 healthy older participants as well as in 10 older participants with cognitive impairment. Correlations between the two tests were calculated. Also, simulated driving performance was used to group the participants into good performers (n=70) and poor performers (n=10). A receiver-operating characteristic analysis was calculated to determine sensitivity and specificity of the wBCST in predicting simulated driving performance.
The mean wBCST score of the participants with poor simulated driving performance was reduced by 52%, compared to participants with good simulated driving performance (P<.001). The area under the receiver-operating characteristic curve was 0.80 with a 95% confidence interval 0.68-0.92.
When selecting a 75% test score as the cutoff, the novel test has 83% sensitivity, 70% specificity, and 81% efficiency, which are good values for a screening test. Overall, in this pilot study, the novel Web-based computer test appears to be a promising tool for supporting clinicians in fitness-to-drive assessments of older drivers. The Web-based distribution and scoring on a central computer will facilitate further evaluation of the novel test setup. We expect that in the near future, Web-based computer tests will become a valid and reliable tool for clinicians, for example, when assessing fitness to drive in older drivers.
cognitive impairment; Web-based cognitive test; computer-based tests; driving simulation
The purpose of this article is to review the literature on the ability of individuals with dementia to drive an automobile. Based on a review of the literature, several factors were identified that may be useful in differentiating between people with dementia who presently remain safe drivers from those who have progressed to impaired driving. These factors include disease duration and severity, sex, patient self-assessment, family assessment, neuropsychological measures, findings on road evaluations, and driving simulator testing. The approach of the physician to driving and dementia is addressed, including in-office screening, referral for on-road driving assessments, and the potential for physician reporting to state agencies.
dementia; driving; competence; impairment
To review the evidence regarding the usefulness of patient demographic characteristics, driving history, and cognitive testing in predicting driving capability among patients with dementia and to determine the efficacy of driving risk reduction strategies.
Systematic review of the literature using the American Academy of Neurology's evidence-based methods.
For patients with dementia, consider the following characteristics useful for identifying patients at increased risk for unsafe driving: the Clinical Dementia Rating scale (Level A), a caregiver's rating of a patient's driving ability as marginal or unsafe (Level B), a history of crashes or traffic citations (Level C), reduced driving mileage or self-reported situational avoidance (Level C), Mini-Mental State Examination scores of 24 or less (Level C), and aggressive or impulsive personality characteristics (Level C). Consider the following characteristics not useful for identifying patients at increased risk for unsafe driving: a patient's self-rating of safe driving ability (Level A) and lack of situational avoidance (Level C). There is insufficient evidence to support or refute the benefit of neuropsychological testing, after controlling for the presence and severity of dementia, or interventional strategies for drivers with dementia (Level U).
= American Academy of Neurology;
= Alzheimer disease;
= Clinical Dementia Rating;
= confidence interval;
= Mini-Mental State Examination;
= odds ratio;
= on-road driving test;
= Quality Standards Subcommittee;
= relative risk.
This study aimed to develop predictive models for real-life driving outcomes in older drivers. Demographics, driving history, on-road driving errors, and performance on visual, motor, and neuropsychological test scores at baseline were assessed in 100 older drivers (ages 65–89 years [72.7]). These variables were used to predict time to driving cessation, first moving violation, or crash. Using Cox proportional hazards regression models, significant individual predictors for driving cessation were greater age and poorer scores on Near Visual Acuity, Contrast Sensitivity, Useful Field of View, Judgment of Line Orientation, Trail Making Test-Part A, Benton Visual Retention Test, Grooved Pegboard, and a composite index of overall cognitive ability. Greater weekly mileage, higher education, and “serious” on-road errors predicted moving violations. Poorer scores from Trail Making Test-Part B or Trail Making Test (B-A) and serious on-road errors predicted crashes. Multivariate models using “off-road” predictors revealed (1) age and Contrast Sensitivity as best predictors for driving cessation; (2) education, weekly mileage, and Auditory Verbal Learning Task-Recall for moving violations; and (3) education, number of crashes over the past year, Auditory Verbal Learning Task-Recall, and Trail Making Test (B-A) for crashes. Diminished visual, motor, and cognitive abilities in older drivers can be easily and noninvasively monitored with standardized off-road tests, and performances on these measures predict involvement in motor vehicle crashes and driving cessation, even in the absence of a neurological disorder.
neuropsychological tests; safety errors; driving cessation; instrumented vehicle
The aims of this study were to determine whether perceived sense of direction was associated with the driving space of older drivers and whether the association was different between genders. Participants (1,425 drivers aged 67–87 years) underwent a battery of visual and cognitive tests and completed various questionnaires. Sense of direction was assessed using the Santa Barbara Sense of Direction (SBSOD) scale. Driving space was assessed by both the driving space component of the Driving Habits Questionnaire and log maximum area driven. Analyses were performed using generalized linear models. The SBSOD score was lower in women than in men and significantly associated with log driving area in women but not in men. The SBSOD score also showed a significant association with women’s self-reported driving restriction. The findings emphasize the need to explore the role of psychological factors, and include gender, in driving studies and models.
Drivers; Driving restriction; Driving space; Gender; Navigational ability; Sense of direction
There are various methods to examine driving ability. Comparisons between these methods and their relationship with actual on-road driving is often not determined.
The objective of this study was to determine whether laboratory tests measuring driving-related skills could adequately predict on-the-road driving performance during normal traffic.
Ninety-six healthy volunteers performed a standardized on-the-road driving test. Subjects were instructed to drive with a constant speed and steady lateral position within the right traffic lane. Standard deviation of lateral position (SDLP), i.e., the weaving of the car, was determined. The subjects also performed a psychometric test battery including the DSST, Sternberg memory scanning test, a tracking test, and a divided attention test. Difference scores from placebo for parameters of the psychometric tests and SDLP were computed and correlated with each other. A stepwise linear regression analysis determined the predictive validity of the laboratory test battery to SDLP.
Stepwise regression analyses revealed that the combination of five parameters, hard tracking, tracking and reaction time of the divided attention test, and reaction time and percentage of errors of the Sternberg memory scanning test, together had a predictive validity of 33.4%.
The psychometric tests in this test battery showed insufficient predictive validity to replace the on-the-road driving test during normal traffic.
Driving; SDLP; Psychometric tests; Predictive validity
The present study examined if knowledge of driving laws independently predicts on-the-road driving performance among cognitively impaired older adults.
The current study consisted of retrospective observational analyses on 55 cognitively impaired older adults (77.9 ± 6.4 years) that completed an on-the-road driving evaluation, a 20-item knowledge test of driving laws, and a brief cognitive test battery.
Logistic regression found poorer performance on the knowledge test was significantly associated with greater likelihood of recommended driving cessation beyond important demographic and cognitive variables (p < 0.05).
Cognitively impaired patients’ ability to drive may be related to their knowledge regarding common driving laws, in addition to their current level of cognitive functioning.
Cognitive impairment; Driving performance; Driving license; Road traffic; Knowledge of driving laws
Cognitive impairment is prevalent in older adults with heart failure (HF) and associated with reduced functional independence. HF patients appear at risk for reduced driving ability, as past work in other medical samples has shown cognitive dysfunction to be an important contributor to driving performance. The current study examined whether cognitive dysfunction was independently associated with reduced driving simulation performance in a sample of HF patients.
18 persons with HF (67.72; SD = 8.56 year) completed echocardiogram and a brief neuropsychological test battery assessing global cognitive function, attention/executive function, memory and motor function. All participants then completed the Kent Multidimensional Assessment Driving Simulation (K-MADS), a driving simulator scenario with good psychometric properties.
The sample exhibited an average Mini Mental State Examination (MMSE) score of 27.83 (SD = 2.09). Independent sample t-tests showed that HF patients performed worse than healthy adults on the driving simulation scenario. Finally, partial correlations showed worse attention/executive and motor function were independently associated with poorer driving simulation performance across several indices reflective of driving ability (i.e., centerline crossings, number of collisions, % of time over the speed limit, among others).
The current findings showed that reduced cognitive function was associated with poor simulated driving performance in older adults with HF. If replicated using behind-the-wheel testing, HF patients may be at elevated risk for unsafe driving and routine driving evaluations in this population may be warranted.
Driving simulation; Heart failure; Cognitive function; Driving ability
This study was designed to examine the on-road driving performance of drivers with hemianopia and quadrantanopia compared with age-matched controls.
Participants included persons with hemianopia or quadrantanopia and those with normal visual fields. Visual and cognitive function tests were administered, including confirmation of hemianopia and quadrantanopia through visual field testing. Driving performance was assessed using a dual-brake vehicle and monitored by a certified driving rehabilitation specialist. The route was 14.1 miles of city and interstate driving. Two “back-seat” evaluators masked to drivers’ clinical characteristics independently assessed driving performance using a standard scoring system.
Participants were 22 persons with hemianopia and 8 with quadrantanopia (mean age, 53 ± 20 years) and 30 participants with normal fields (mean age, 52 ± 19 years). Inter-rater agreement for back-seat evaluators was 96%. All drivers with normal fields were rated as safe to drive, while 73% (16/22) of hemianopic and 88% (7/8) of quadrantanopic drivers received safe ratings. Drivers with hemianopia or quadrantanopia who displayed on-road performance problems tended to have difficulty with lane position, steering steadiness, and gap judgment compared to controls. Clinical characteristics associated with unsafe driving were slowed visual processing speed, reduced contrast sensitivity and visual field sensitivity.
Some drivers with hemianopia or quadrantanopia are fit to drive compared with age-matched control drivers. Results call into question the fairness of governmental policies that categorically deny licensure to persons with hemianopia or quadrantanopia without the opportunity for on-road evaluation.
Background. Cognitive deterioration may impair COPD patient's ability to perform tasks like driving vehicles. We investigated: (a) whether subclinical neuropsychological deficits occur in stable COPD patients with mild hypoxemia (PaO2 > 55 mmHg), and (b) whether these deficits affect their driving performance. Methods. We recruited 35 stable COPD patients and 10 normal subjects matched for age, IQ, and level of education. All subjects underwent an attention/alertness battery of tests for assessing driving performance based on the Vienna Test System. Pulmonary function tests, arterial blood gases, and dyspnea severity were also recorded. Results. COPD patients performed significantly worse than normal subjects on tests suitable for evaluating driving ability. Therefore, many (22/35) COPD patients were classified as having inadequate driving ability (failure at least in one of the tests), whereas most (8/10) healthy individuals were classified as safe drivers (P = 0.029). PaO2 and FEV1 were correlated with almost all neuropsychological tests. Conclusions. COPD patients should be warned of the potential danger and risk they face when they drive any kind of vehicle, even when they do not exhibit overt symptoms related to driving inability. This is due to the fact that stable COPD patients may manifest impaired information processing operations.
Parkinson’s disease (PD) impairs driving performance. In this pilot study, four drivers with PD (selected based on poor road driving performance in the past) participated in a rehabilitation program using a driving simulator. Two different training drives (#1- multiple intersections of varying visibility and traffic load, where an incurring vehicle posed a crash risk, #2- various scenarios on decision making, hazard perception and response) were administered in each session (total 3 sessions once every 1–2 weeks) with immediate feedback after the drives. We observed reduction in crashes in drive #1 and improved scores on drive #2 in the simulator. In addition, 3 subjects showed marked improvements in their total error counts on a standard road test between baseline and post-training sessions, one subject stayed stable. These findings suggest that our simulator training program is feasible and potentially useful in impaired drivers with PD.