A comparative approach to identify unsafe older drivers

The Assessment of Driving Fitness Using an On-Road Evaluation in Patients With Cirrhosis

INTRODUCTION

The association between cirrhosis and driving performance is of particular clinical relevance because of the life-threatening safety issues both for the driver with cirrhosis and the general public. Study aims were to assess (i) driving competency through the use of an in-office computerized battery and on-road driving assessment (DriveABLE) and (ii) the association between minimal hepatic encephalopathy (MHE), in-office paper-pencil tools, and additional measures (e.g., frailty, depression, cognitive testing) with unsafe driving.

METHODS

Patients were prospectively recruited from 2 tertiary care liver clinics. In-office tests and in-office and on-road assessments of driving competence were completed. The χ 2 test and 1-way analysis of variance were used to analyze differences among those with and without MHE. Logistic regression was used to evaluate predictors of an indeterminate/fail result on the in-office computerized driving assessment battery (DriveABLE Cognitive Assessment Tool [DCAT]).

RESULTS

Eighty patients participated with a mean age of 57 years, 70% male, 75% Child-Pugh B/C, and 36% with a history of overt hepatic encephalopathy. Thirty percent met MHE criteria on both the psychometric hepatic encephalopathy score and the Stroop app tests. Only 2 patients (3%) were categorized as "unfit to drive" in the on-road driving test, one with MHE and the other without. Fifty-eight percent of the patients were scored as indeterminate/fail on the DCAT. This corresponded to a higher mean number of on-road driving errors (5.3 [SD 2.1] vs 4.2 [SD 1.6] in those who passed the DCAT, P = 0.01). Older age (odds ratio 1.3; confidence interval 1.1, 1.5; P = 0.001) and MHE by Stroop/psychometric hepatic encephalopathy score (odds ratio 11.0; confidence interval 2.3, 51.8; P = 0.002) were independently predictive of worse performance on the DCAT.

DISCUSSION

Worse performance in in-office testing was associated with worse scores on a computerized driving assessment battery and more on-road driving errors, but in-office tools were insufficient to predict on-road driving failures. A diagnosis of MHE should not be used alone to restrict driving in patients with cirrhosis. At-risk patients require on-road driving tests under the supervision of driving regulatory agencies. Future studies should continue to refine and evaluate in-office or at-home testing to predict driving performance.

Comparison of older and middle-aged drivers' driving performance in a naturalistic setting

There is a concern in the public domain about driving safety among older drivers due the increase in age-associated medical conditions. It is not known how these medical changes impact driving performance and choice of driving environment. This study aimed to compare older drivers' (≥74 years) driving performance in a naturalistic setting to middle-aged drivers (35-64 years) on their chosen driving environment, and number, type and severity of errors. The effect of sex and perceived driving ability was also examined. Drivers' performance was studied using the electronic Driving Observation Schedule [eDOS]), a naturalistic observation approach. Fifty-three older (mean age = 80.6 years, 72% male) and 60 middle-aged (mean age = 50.0 years, 50% male) healthy drivers were recruited. Both groups made few driving errors that were mostly low-risk. Driving performance of older adults differed from middle-aged drivers; they drove on simpler routes (fewer intersections and lane changes) and made fewer errors. Findings are likely indicative of older drivers' use of adaptive strategies to maintain safe driving.

The short-term effects of artificially-impaired binocular vision on driving performance

Appropriate visual function is paramount to ensuring adequate driving performance and road safety. Here, we examined the influence of sudden artificially-impaired binocular vision on driving performance using a car simulator. Twenty-four young drivers (mean age 22.42 ± 3.19 years) drove under three different visual conditions (natural driving, monocular blur, and monocular occlusion) through three different traffic environments with low, medium, and high levels of complexity (highway, rural, and city, respectively). We assessed their driving performance, perceived level of task complexity, and subjectively-experienced road safety. Furthermore, as a manipulation check, we also evaluated the drivers' cardiac vagal responses, as a well-known index of task complexity. The sudden deterioration of binocular vision caused unsafe driving behaviours (distance out of the road and maximum breaking intensity) in the most complex traffic environments. Specific self-regulatory strategies (i.e. increased cardiac vagal responses) and subjective responses corroborated these results. Practitioner summary: This study provides evidence that the sudden deterioration of binocular vision has a detrimental effect on simulated driving performance. Our analysis of cardiovascular functioning shows that drivers adopt self-regulatory strategies when their binocular vision functioning is compromised. Abbreviations: VA: visual acuity; BV: binocular vision; HRV: heart rate variability; NASA: TLX: NASA-Task Load Index; SSS: Stanford Sleepiness scale; RMSSD: root mean square of successive difference; HF: high-frequency.

Development of a weighted scoring system for the Electronic Driving Observation Schedule (eDOS)

The electronic Driving Observation Schedule (eDOS) is a novel approach to assessing older drivers' performance in their everyday driving environment on their chosen routes. The original eDOS total score is generated using the count of driving errors, which does not account for distinct risk levels of different types of driving errors made in different complexity of driving environments. This study was conducted to create one score to represent the complexity of driving route during each eDOS observation and one weighted eDOS total score to represent older drivers' performance accounting for the risk of driving errors by their type and the complexity of maneuvers in their corresponding environments. A literature review, a two-round survey with 13 experts in driving evaluation, and iterative discussions between primary investigators were conducted for generating these scores. Two formulae were created to calculate a weighted maneuver/environmental complexity score and a weighted eDOS total score. •An advanced weighted score is created to represent one's on-road driving performance in their everyday driving environment not only using the count of driving errors, but also accounting for the risk level of each error.•The complexity of driving maneuver and environment in each on-road driving trip can be systematically rated.

Reliability and validity of on-road driving tests in vulnerable adults: a systematic review

The on-road driving test is considered a ‘gold standard’ evaluation; however, its validity and reliability have not been sufficiently reviewed. This systematic review aimed to map out and synthesize literature regarding on-road driving tests using the Consensus-based Standards for the Selection of Health Measurement Instruments checklist. Cochrane Library, PubMed, CINAHL, and Web of Science databases were searched from initiation through February 2018. All articles addressing reliability or validity of on-road driving tests involving adult rehabilitation patients were included. The search output identified 513 studies and 36 articles, which were included in the review. The Washington University Road Test/Rhode Island Road Test, performance analysis of driving ability, test ride for investigating practical fitness-to-drive, and K-score demonstrated high reliability and validity in regard to the Consensus-based Standards for the Selection of Health Measurement Instruments checklist. The Washington University Road Test/Rhode Island Road Test and test ride for investigating practical fitness-to-drive were analyzed based on Classical Test Theory techniques, and performance analysis of driving ability and K-score were analyzed based on Item Response Theory techniques. The frequency of studies were Washington University Road Test/Rhode Island Road Test (n=9), Test Ride for Investigating Practical fitness-to-drive (n=8), performance analysis of driving ability (n=4), and K-score (n=1). From the viewpoint of accuracy and generalization, the Washington University Road Test/Rhode Island Road Test, test ride for investigating practical fitness-to-drive, and performance analysis of driving ability were identified as highly qualified concerning on-road driving tests. However, the ability to assess real-world driving depends on various environmental conditions.

Age-related Differences in Driving: Are Older Drivers More Serial?

A measurement-instrumented car was used to test the hypothesis that older drivers organise their car-controlling movements in a more serial way in order to reduce the momentary mental workload produced by complex traffic situations. Forty-two older drivers (65+, mean age 67.5) and 36 young middle-aged drivers (26-49, mean age 36.8) drove a measurement-instrumented car around a 7.4 km route in normal traffic. The use of car controls (e.g. clutch, brake) was registered by sensors connected to a computer. In the most complex parts of the test route (e.g. during which three or more controls were in use simultaneously), the older drivers tended to use three controls rather than four or more, whereas the younger group had a greater percentage of four or more controls. This percentage was positively related to speed. However, although older drivers drove more slowly in general, in pairs matched for speed, they still drove in a less parallel manner. Irrespective of age, parallel use of controls was positively related to the level of skill as indicated by the amount of cumulated driving experience. The shift towards more serial operation of controls possibly represents an empirical demonstration of a compensatory mechanism allowing older drivers to maintain their level of performance.

License Suspension Revisited: A 3-Year Follow-Up Study of Older Drivers

This 3-year follow-up study addressed changes in health, cognitive functioning, and driving status among 37 older drivers and 37 individually matched controls. Initially, the study group had suspended driver’s licenses due to traffic violations. The in-person follow-up medical and neuropsychological examinations concerned 20 case participants and 22 controls. Mortality tended to be higher with case participants than with controls (p = .085), and there was more dementia or cognitive impairment with case participants (5/37) than with controls (0/37,p = .027). Initially, crash-involved case participants performed consistently worse on measures of cognitive functioning than did controls and noncrashed case participants and showed greater deterioration over time. Compared to controls, more crash-involved drivers had died (p = .019) or had stopped driving (p = .040). Because some older drivers with unsafe driving behavior may be in early phases of dementing processes or serious medical conditions, they should be medically and cognitively assessed.

Driving Task: How Older Drivers' On-Road Driving Performance Relates to Abilities, Perceptions, and Restrictions

This study examined a cohort of 227 older drivers and investigated the relationship between performance on the electronic Driver Observation Schedule (eDOS) driving task and: (1) driver characteristics; (2) functional abilities; (3) perceptions of driving comfort and abilities; and (4) self-reported driving restrictions. Participants (male: 70%; age: M = 81.53 years, SD = 3.37 years) completed a series of functional ability measures and scales on perceived driving comfort, abilities, and driving restrictions from the Year 2 Candrive/Ozcandrive assessment protocol, along with an eDOS driving task. Observations of participants' driving behaviours during the driving task were recorded for intersection negotiation, lane-changing, merging, low-speed maneuvers, and maneuver-free driving. eDOS driving task scores were high (M = 94.74; SD = 5.70) and significantly related to participants' perceived driving abilities, reported frequency of driving in challenging situations, and number of driving restrictions. Future analyses will explore potential changes in driving task scores over time.

Functional Changes and Driving Performance in Older Drivers: Assessment and Interventions

With the increasing aging of the population, the number of older drivers is rising. Driving is a significant factor for quality of life and independence concerning social and working life. On the other hand, driving is a complex task involving visual, motor, and cognitive skills that experience age-related changes even in healthy aging. In this review we summarize different age-related functional changes with relevance for driving concerning sensory, motor, and cognitive functions. Since these functions have great interindividual variability, it is necessary to apply methods that help to identify older drivers with impaired driving abilities in order to take appropriate measures. We discuss three different methods to assess driving ability, namely the assessment of (i) functions relevant for driving; (ii) driving behavior in real traffic; and (iii) behavior in a driving simulator. We present different measures to improve mobility in older drivers, including information campaigns, design of traffic and car environment, instructions, functional training, and driving training in real traffic and in a driving simulator. Finally, we give some recommendations for assessing and improving the driving abilities of older drivers with multi-modal approaches being most promising for enhancing individual and public safety.

Screening and assessment tools for determining fitness to drive: a review of the literature for the pathways project

With a brief introduction, 10 tables summarize the findings from the literature describing screening and assessment tools used with older adults to identify risk or determine fitness to drive. With a focus on occupational therapy's duty to address driving as a valued activity, this paper offers information about tools used by occupational therapy practitioners across practice settings and specialists in driver rehabilitation. The tables are organized into groups of key research studies of assessment tools, screening batteries, tools used in combination (i.e., as a battery), driving simulation as an assessment tool, and screening/assessment for individuals with stroke, vision impairment, Parkinson's disease, dementia, and aging. Each table has a summary of important concepts to consider as occupational therapists choose the methods and tools to evaluate fitness to drive.

Reliability of P-drive in occupational therapy following a short training session: A promising instrument measuring seniors’ on-road driving competencies

Introduction

Occupational therapists could play an important role in facilitating driving cessation for ageing drivers. This, however, requires an easy-to-learn, standardised on-road evaluation method. This study therefore investigates whether use of ‘P-drive’ could be reliably taught to occupational therapists via a short half-day training session.

Method

Using the English 26-item version of P-drive, two occupational therapists evaluated the driving ability of 24 home-dwelling drivers aged 70 years or over on a standardised on-road route. Experienced driving instructors’ on-road, subjective evaluations were then compared with P-drive scores.

Results

Following a short half-day training session, P-drive was shown to have almost perfect between-rater reliability (ICC2,1 = 0.950, 95% CI 0.889 to 0.978). Reliability was stable across sessions including the training phase even if occupational therapists seemed to become slightly less severe in their ratings with experience. P-drive’s score was related to the driving instructors’ subjective evaluations of driving skills in a non-linear manner ( R2 = 0.445, p = 0.021).

Conclusion

P-drive is a reliable instrument that can easily be taught to occupational therapists and implemented as a way of standardising the on-road driving test.

On-road driving assessment and route design for drivers with dementia

Introduction

Dementia causes the progressive loss of cognitive capacities and thus impairs social and daily living skills. Dementia, to varying degrees, influences driver performance and safety. Eventually drivers affected by dementia must stop driving so they do not harm themselves or others. However, having to stop driving can result in loss of mobility and social connections. Therefore, assessing drivers with dementia is important. Driving assessment is susceptible to possible biases, including unreliable driving performance measures or driving routes that are inconsistent in the levels of difficulty of the driving tasks and manoeuvres. The aim of the study was to determine what measures of driving performance could optimally be applied to occupational therapy on-road driving assessments.

Method

All drivers with dementia underwent a 60 minute, set route on-road driving assessment that consisted of 110 pre-programmed observation points.

Results

The study identified 80 sufficiently challenging driving tasks and described the relationship of driving error to that task, for example, critical errors at unguided intersections.

Conclusion

The results of the task-demand by error type analysis identified a list of task items that can be applied to assessment route design to increase consistency of on-road assessment for people with dementia.

Predicting on-road driving performance and safety in healthy older adults

INTRODUCTION

This study evaluated the ability to predict the on-road driving of older drivers using a battery of laboratory-based instruments.

METHODS

The Roadwise Review, a brief Hazard Perception Test and several tests of vision were given to 65 cognitively healthy, licensed older drivers (M = 74 years, SD = 9 years). They also participated in a standardized driving assessment of approximately 18 km, along a mixed residential and commercial route.

RESULTS

Raw scores on the Roadwise Review did not predict accumulated points, or automatic disqualifications, but could predict who would pass or fail the on-road evaluation. The number of serious problems (excluding head and neck flexibility) that were identified by the Roadwise Review was a significant predictor of automatic disqualifications, and a significant predictor of passing or failing the on-road assessment. The Hazard Perception Test approached significance when predicting accumulated points and was a significant predictor of automatic disqualifications, as well as pass/fail outcomes.

CONCLUSIONS

The best model for predicting passing or failing the on-road assessment included the Hazard Perception Test, color vision, and, a measure of walking speed from the Roadwise Review, which yielded a sensitivity of 82% and a specificity of 69% (AROC = .80). Future work will need to determine how these tests can be used with other information (e.g., medical history) to yield better diagnoses of fitness to drive, particularly among those who are medically at risk.

A neuropsychological instrument measuring age-related cerebral decline in older drivers: development, reliability, and validity of MedDrive

When facing age-related cerebral decline, older adults are unequally affected by cognitive impairment without us knowing why. To explore underlying mechanisms and find possible solutions to maintain life-space mobility, there is a need for a standardized behavioral test that relates to behaviors in natural environments. The aim of the project described in this paper was therefore to provide a free, reliable, transparent, computer-based instrument capable of detecting age-related changes on visual processing and cortical functions for the purposes of research into human behavior in computational transportation science. After obtaining content validity, exploring psychometric properties of the developed tasks, we derived (Study 1) the scoring method for measuring cerebral decline on 106 older drivers aged ≥70 years attending a driving refresher course organized by the Swiss Automobile Association to test the instrument's validity against on-road driving performance (106 older drivers). We then validated the derived method on a new sample of 182 drivers (Study 2). We then measured the instrument's reliability having 17 healthy, young volunteers repeat all tests included in the instrument five times (Study 3) and explored the instrument's psychophysical underlying functions on 47 older drivers (Study 4). Finally, we tested the instrument's responsiveness to alcohol and effects on performance on a driving simulator in a randomized, double-blinded, placebo, crossover, dose-response, validation trial including 20 healthy, young volunteers (Study 5). The developed instrument revealed good psychometric properties related to processing speed. It was reliable (ICC = 0.853) and showed reasonable association to driving performance (R (2) = 0.053), and responded to blood alcohol concentrations of 0.5 g/L (p = 0.008). Our results suggest that MedDrive is capable of detecting age-related changes that affect processing speed. These changes nevertheless do not necessarily affect driving behavior.

A novel computer test to assess driving-relevant cognitive functions--a pilot study

BACKGROUND

The assessment of driving-relevant cognitive functions in older drivers is a difficult challenge as there is no clear-cut dividing line between normal cognition and impaired cognition and not all cognitive functions are equally important for driving.

METHODS

To support decision makers, the Bern Cognitive Screening Test (BCST) for older drivers was designed. It is a computer-assisted test battery assessing visuo-spatial attention, executive functions, eye-hand coordination, distance judgment, and speed regulation. Here we compare the performance in BCST with the performance in paper and pencil cognitive screening tests and the performance in the driving simulator testing of 41 safe drivers (without crash history) and 14 unsafe drivers (with crash history).

RESULTS

Safe drivers performed better than unsafe drivers in BCST (Mann-Whitney U test: U = 125.5; p = 0.001) and in the driving simulator (Student's t-test: t(44) = -2.64, p = 0.006). No clear group differences were found in paper and pencil screening tests (p > 0.05; ns). BCST was best at identifying older unsafe drivers (sensitivity 86%; specificity 61%) and was also better tolerated than the driving simulator test with fewer dropouts.

CONCLUSIONS

BCST is more accurate than paper and pencil screening tests, and better tolerated than driving simulator testing when assessing driving-relevant cognition in older drivers.

Development and evaluation of a driving observation schedule (DOS) to study everyday driving performance of older drivers

This paper describes the development and evaluation of an on-road procedure, the Driving Observation Schedule (DOS), for monitoring individual driving behavior. DOS was developed for use in the Candrive/Ozcandrive five-year prospective study of older drivers. Key features included observations in drivers' own vehicles, in familiar environments chosen by the driver, with start/end points at their own homes. Participants were 33 drivers aged 75+ years, who drove their selected route with observations recorded during intersection negotiation, lane-changing, merging, low speed maneuvers and maneuver-free driving. Driving behaviors were scored by a specialist occupational therapy driving assessor and another trained observer. Drivers also completed a post-drive survey about the acceptability of DOS. Vehicle position, speed, distance and specific roadways traveled were recorded by an in-vehicle device installed in the participant's vehicle; this device was also used to monitor participants' driving over several months, allowing comparison of DOS trips with their everyday driving. Inter-rater reliability and DOS feasibility, acceptability and ecological validity are reported here. On average, drivers completed the DOS trip in 30.48min (SD=7.99). Inter-rater reliability measures indicated strong agreement between the trained and the expert observers: intra-class correlations (ICC)=0.905, CI 95% 0.747-0.965, p<0.0001; Pearson product correlation, r (18)=.83, p<0.05. Standard error of the measurement (SEM), method error (ME) and coefficient of variation (CV) measures were consistently small (3.0, 2.9 & 3.3%, respectively). Most participants reported being 'completely at ease' (82%) with the driving task and 'highly familiar with the route' (97%). Vehicle data showed that DOS trips were similar to participants' everyday driving trips in roads used, roadway speed limits, drivers' average speed and speed limit compliance. In summary, preliminary findings suggest that DOS can be scored reliably, is of feasible duration, is acceptable to drivers and representative of everyday driving. Pending further research with a larger sample and other observers, DOS holds promise as a means of quantifying and monitoring changes in older drivers' performance in environments typical of their everyday driving.

How effective is the Trail Making Test (Parts A and B) in identifying cognitively impaired drivers?

BACKGROUND

the medical community plays an important role in identifying drivers who may no longer be competent to drive due to illnesses such as dementia. Several office-based cognitive screening tools are currently used by the medical community, e.g. Mini-Mental State Examination, Trail Making Test (TMT), to assist in the identification of cognitively impaired (CI) at-risk drivers. However, the predictive validity of these tools is questionable.

OBJECTIVE

to examine the predictive power of the TMT for on-road driving performance.

METHODS

data from a prospective sample of CI and healthy older drivers were collected. TMT-A and -B (time and errors) served as predictor variables, with pass/fail on a scientifically based on-road assessment used as the criterion variable. Receiver operating characteristic (ROC) curve analysis was used to assess overall 'diagnostic' accuracy of TMT-A and -B for driving competency. Cut points from previous studies/guidelines were used to assess predictive power.

FINDINGS

a total of 134 older drivers (mean age = 75.30; SD = 7.83) participated: 87 healthy controls and 47 CI individuals. All predictor variables, with the exception of TMT-A errors, were significantly correlated with driving outcome. However, results from ROC curve analyses indicated that only TMT-A and -B total time had moderate discriminative abilities. Results also indicate that the power of the TMT is the lowest where physicians need it most (e.g. identifying CI patients whose driving skills have declined to an unsafe level).

CONCLUSION

TMT-A and -B outcomes are most likely to be inaccurate in those whose driving competency has declined to an unsafe level, resulting in risks to both individual and public safety.

Driving assessment for maintaining mobility and safety in drivers with dementia

BACKGROUND

Demographic changes are leading to an increase in the number of older drivers: as dementia is an age-related disease, there is also an increase in the numbers of drivers with dementia. Dementia can impact on both the mobility and safety of drivers, and the impact of formal assessment of driving is unknown in terms of either mobility or safety. Those involved in assessment of older drivers need to be aware of the evidence of positive and negative effects of driving assessment. Cognitive tests are felt by some authors to have poor face and construct validity for assessing driving performance; extrapolating from values in one large-scale prospective cohort study, the cognitive test that most strongly predicted future crashes would, if used as a screening tool, potentially prevent six crashes per 1000 people over 65 years of age screened, but at the price of stopping the driving of 121 people who would not have had a crash.

OBJECTIVES

PRIMARY OBJECTIVES

1. to assess whether driving assessment facilitates continued driving in people with dementia;2. to assess whether driving assessment reduces accidents in people with dementia.

SECONDARY OBJECTIVE

1. to assess the quality of research on assessment of drivers with dementia.

SEARCH METHODS

ALOIS, the Cochrane Dementia Group's Specialized Register was searched on 13 September 2012 using the terms: driving or driver* or "motor vehicle*" or "car accident*" or "traffic accident*" or automobile* or traffic. This register contains records from major healthcare databases, ongoing trial databases and grey literature sources and is updated regularly.

SELECTION CRITERIA

We sought randomised controlled trials prospectively evaluating drivers with dementia for outcomes such as transport mobility, driving cessation or motor vehicle accidents following driving assessment.

DATA COLLECTION AND ANALYSIS

Each review author retrieved studies and assessed for primary and secondary outcomes, study design and study quality.

MAIN RESULTS

No studies were found that met the inclusion criteria. A description and discussion of the driving literature relating to assessment of drivers with dementia relating to the primary objectives is presented.

AUTHORS' CONCLUSIONS

In an area with considerable public health impact for drivers with dementia and other road users, the available literature fails to demonstrate the benefit of driver assessment for either preserving transport mobility or reducing motor vehicle accidents. Driving legislation and recommendations from medical practitioners requires further research that addresses these outcomes in order to provide the best outcomes for both drivers with dementia and the general public.

Quantifying age-related differences in visual-discrimination capacity: drivers with and without visual impairment

The aim of this study is to examine the effects of aging as well as visual impairment on retinal-image quality and visual performance in drivers. We use a new visual test called Halo v1.0 software for quantifying the discrimination capacity, an important visual function for evaluating the visual disturbances perceived by the observer. The study included 55 subjects with normal vision and 15 older subjects with cataracts. All subjects were examined for visual acuity, contrast sensitivity, visual-discrimination capacity and optical quality. Subjects also completed a subjective Driving Habits Questionnaire (DHQ). Older drivers with and without visual impairment showed significantly (p < 0.05) worse visual performance and deteriorated retinal-image quality, even when their binocular visual acuity was ≥20/25. In conclusion, some visual functions are considerably diminished in older drivers, even when visual acuity is sufficient to get or renew a driver's license. Halo software enables easy quantification of night-vision disturbances such as halos, which could impede the detection of pedestrians, cyclists, or traffic signals, thereby making this system advisable in clinical practice, e.g. in the requirements for a driver's license, particularly for older drivers.

The Introduction of a New Screening Tool for the Identification of Cognitively Impaired Medically At-Risk Drivers: The SIMARD A Modification of the DemTect

The number of drivers with a cognitive impairment due to dementia or other age-associated pathologies will increase significantly over the next 3 decades. Physicians are well placed to identify medically at-risk drivers, but are hampered by the lack of a valid, easy to administer screening tool. This research develops and validates a brief screening tool for use in the primary care setting to identify drivers with cognitive impairment with or without dementia. Initial Study Participants: A cohort of 146 consecutive referrals from community-based family physicians, diagnosed with an undifferentiated cognitive impairment or dementia, as well as 35 community dwelling healthy controls. Validation Study: A cohort of 192 consecutive referrals carrying the same diagnosis as above and 52 community dwelling healthy controls. Criterion Measure: Pass/fail on an On-Road evaluation. Predictor Measures: Subtests of the DemTect, a screening test for cognitive impairment or dementia developed by Kalbe and colleagues.(1) Initial Study: Three of the DemTect measures predicted On-Road outcomes (R(2) = .262). Regression results were used to develop a simple scoring algorithm, with cut-points then derived by identifying those most at risk for failing and passing the On-Road assessment, and those needing a driving assessment for determination of driving competency. 89 individuals scored in the indeterminate range, with 49 and 43 predicted to fail and pass, respectively-86% and 84% of those predicted to fail and pass did subsequently fail and pass. Validation Study: 123 individuals scored in the indeterminate range, with 66 and 55 predicted to fail and pass, respectively-80% and 87% of those predicted to fail and pass did subsequently fail and pass.

CONCLUSIONS

The SIMARD A Modification of the DemTect ( S creen for the I dentification of cognitively impaired M edically A t- R isk D rivers) is a brief paper and pencil screening tool with a high degree of accuracy that can be used for immediate decisions in the clinical setting.

Driving assessment for maintaining mobility and safety in drivers with dementia

BACKGROUND

Demographic changes are leading to an increase in the number of older drivers: as dementia is an age-related disease, there is also an increase in the numbers of drivers with dementia. Dementia can impact on both the mobility and safety of drivers, and the impact of formal assessment of driving is unknown in terms of either mobility or safety. Those involved in assessment of older drivers need to be aware of the evidence of positive and negative effects of driving assessment. Cognitive tests are felt by some authors to have poor face and construct validity for assessing driving performance; extrapolating from values in one large-scale prospective cohort study, the cognitive test that most strongly predicted future crashes would, if used as a screening tool, potentially prevent six crashes per 1000 people over 65 years of age screened, but at the price of stopping the driving of 121 people who would not have had a crash.

PRIMARY OBJECTIVES

1. to assess whether driving assessment facilitates continued driving in people with dementia; 2. to assess whether driving assessment reduces accidents in people with dementia.

SECONDARY OBJECTIVE

1. to assess the quality of research on assessment of drivers with dementia.

SEARCH METHODS

ALOIS, the Cochrane Dementia Group's Specialized Register was searched on 13 September 2012 using the terms: driving or driver* or "motor vehicle*" or "car accident*" or "traffic accident*" or automobile* or traffic. This register contains records from major healthcare databases, ongoing trial databases and grey literature sources and is updated regularly.

SELECTION CRITERIA

We sought randomised controlled trials prospectively evaluating drivers with dementia for outcomes such as transport mobility, driving cessation or motor vehicle accidents following driving assessment.

DATA COLLECTION AND ANALYSIS

Each review author retrieved studies and assessed for primary and secondary outcomes, study design and study quality.

MAIN RESULTS

No studies were found that met the inclusion criteria. A description and discussion of the driving literature relating to assessment of drivers with dementia relating to the primary objectives is presented.

AUTHORS' CONCLUSIONS

In an area with considerable public health impact for drivers with dementia and other road users, the available literature fails to demonstrate the benefit of driver assessment for either preserving transport mobility or reducing motor vehicle accidents. Driving legislation and recommendations from medical practitioners requires further research that addresses these outcomes in order to provide the best outcomes for both drivers with dementia and the general public.

Age differences in simulated driving performance: compensatory processes

In the context of driving, the reported experiment examines compensatory processes for age-related declines in cognitive ability. Younger (26-40 years) and older (60+ years) participants (n=22 each group) performed a car following task in a driving simulator. Several performance measures were recorded, including assessments of anticipation of unfolding traffic events. Participants also completed a range of measures of cognitive ability - including both fluid and crystallised abilities. Three examples of age-related compensation are reported: (i) older drivers adopted longer headways than younger drivers. Data were consistent with this being compensation for an age-related deficit in complex reaction time; (ii) older drivers with relatively higher cognitive ability anticipated traffic events more frequently, whereas the reverse pattern was found for younger drivers; and, (iii) older drivers with greater crystallised ability were less reliant on spatial ability to maintain lane position. Consistent with theories of 'cognitive reserve', interactions between crystallised ability and age for self-report workload suggested that compensation for age-related cognitive ability deficits required investment of additional effort. Results are considered in the context of the prospects of further assessment of older drivers.

Relationship between retinal nerve fiber layer thickness and driving ability in patients with human immunodeficiency virus infection

BACKGROUND

The aim of this work is to study the possible association between retinal nerve fiber layer (NFL) thickness and driving ability.

METHODS

Thirty-eight drivers including 22 HIV-positive (HIV+) and 16 age-matched HIV-negative controls participants underwent a full ophthalmologic evaluation, including assessment of retinal NFL thickness. In the undilated state with standard optical correction and under standard illumination they also completed a computer-based, wide field-of-view driving simulation in which they were to obey traffic laws, engage in crash avoidance, and pass slower automobiles. Crashes, speeding and traffic light tickets, and off-road excursions contributed to a weighted score of driving errors.

RESULTS

HIV-seropositive participants had a significantly higher weighted error score than control participants (18.4 [9.2] vs. 11.1 [4.5], p = 0.006). NFL thickness was significantly correlated with driving errors (r = -0.51, p = 0.025); there was a trend for participants with a CD4 nadir <100 to have more errors than those with a nadir >100 (29.7 [13.2] vs. 19.3 [8.4], p = 0.056). The highest number of driving errors occurred in individuals with both CD4 <100 and NFL thickness <80.

CONCLUSIONS

Driving ability may be impacted by reductions in retinal nerve fiber layer thickness. Physicians should consider the potential impact that more complex ophthalmologic conditions in HIV-infected patients may have on driving performance.

Older drivers: On-road and off-road test results

Eighty-five volunteer drivers, 65-85 years old, without cognitive impairments impacting on their driving were examined, in order to investigate driving errors characteristic for older drivers. In addition, any relationships between cognitive off-road and on-road tests results, the latter being the gold standard, were identified. Performance measurements included Trail Making Test (TMT), Nordic Stroke Driver Screening Assessment (NorSDSA), Useful Field of View (UFOV), self-rating driving performance and the two on-road protocols P-Drive and ROA. Some of the older drivers displayed questionable driving behaviour. In total, 21% of the participants failed the on-road assessment. Some of the specific errors were more serious than others. The most common driving errors embraced speed; exceeding the speed limit or not controlling the speed. Correlations with the P-Drive protocol were established for NorSDSA total score (weak), UFOV subtest 2 (weak), and UFOV subtest 3 (moderate). Correlations with the ROA protocol were established for UFOV subtest 2 (weak) and UFOV subtest 3 (weak). P-Drive and self ratings correlated weakly, whereas no correlation between self ratings and the ROA protocol was found. The results suggest that specific problems or errors seen in an older person's driving can actually be "normal driving behaviours".

Comparison of a linear and a non-linear model for using sensory-motor, cognitive, personality, and demographic data to predict driving ability in healthy older adults

This study compared the ability of binary logistic regression (BLR) and non-linear causal resource analysis (NCRA) to utilize a range of cognitive, sensory-motor, personality and demographic measures to predict driving ability in a sample of cognitively healthy older drivers. Participants were sixty drivers aged 70 and above (mean=76.7 years, 50% men) with no diagnosed neurological disorder. Test data was used to build classification models for a Pass or Fail score on an on-road driving assessment. The generalizability of the models was estimated using leave-one-out cross-validation. Sixteen participants (27%) received an on-road Fail score. Area under the ROC curve values were .76 for BLR and .88 for NCRA (no significant difference, z=1.488, p=.137). The ROC curve was used to select three different cut-points for each model and to compare classification. At the cut-point corresponding to the maximum average of sensitivity and specificity, the BLR model had a sensitivity of 68.8% and specificity of 75.0% while NCRA had a sensitivity of 75.0% and specificity of 95.5%. However, leave-one-out cross-validation reduced sensitivity in both models and particularly reduced specificity for NCRA. Neither model is accurate enough to be relied on solely for determination of driving ability. The lowered accuracy of the models following leave-one-out cross-validation highlights the importance of investigating models beyond classification alone in order to determine a model's ability to generalize to new cases.

Australian Occupational Therapy Driver Assessors’ Opinions on Improving On-Road Driver Assessment Procedures

OBJECTIVE. We collected practitioner opinions to improve the validity and reliability of the on-road driver assessment procedures used in Australia.

METHOD. We used focus groups to document the views of experienced occupational therapy driver assessors using a purposive sampling method.

RESULTS. Eight focus groups were conducted with 55 clinicians practicing in urban and rural regions. There was strong support for greater standardization of procedures for all tests. For drivers seeking unrestricted (open) licenses, use of standard routes with predetermined assessment points was important where practicable. Where use of a nonstandard route for this purpose was unavoidable, it was important to specify a minimum set of requirements related to route characteristics and assessment items.

CONCLUSION. Australian occupational therapy driver assessors support greater standardization of test routes and procedures to improve reliability and validity. However, the extent to which standardization can be achieved is limited by variable road traffic environments where assessments are conducted.

Driving assessment for maintaining mobility and safety in drivers with dementia

BACKGROUND

Demographic changes are leading to an increase in the number of older drivers: as dementia is an age-related disease, there is also an increase in the numbers of drivers with dementia. Dementia can impact on both the mobility and safety of drivers, and the impact of formal assessment of driving is unknown in terms of either mobility or safety. Those involved in assessment of older drivers need to be aware of the evidence of positive and negative effects of driving assessment. Although cognitive tests are felt by some authors to have poor face and construct validity for assessing driving performance, extrapolating from values in one large-scale prospective cohort study, the cognitive test that most strongly predicted future crashes would, if used as a screening tool, potentially prevent six crashes per 1000 people over 65 screened, but at the price of stopping the driving of 121 people who would not have had a crash.

PRIMARY OBJECTIVES

1. To assess whether driving assessment facilitates continued driving in people with dementia 2. To assess whether driving assessment reduces accidents in people with dementia.

SECONDARY OBJECTIVE

To assess the quality of research on assessment of drivers with dementia.

SEARCH STRATEGY

The Cochrane Dementia Group's Specialized Register was searched on 30 October 2007 using the terms: driving or driver* or "motor vehicle*" or "car accident*" or "traffic accident*" or automobile* or traffic. This register contains records from major healthcare databases, ongoing trial databases and grey literature sources and is updated regularly.

SELECTION CRITERIA

We sought randomized controlled trials prospectively evaluating drivers with dementia for outcomes such as transport mobility, driving cessation or motor vehicle accidents following driving assessment.

DATA COLLECTION AND ANALYSIS

Each author retrieved studies and assessed for primary and secondary outcomes, study design and study quality.

MAIN RESULTS

No studies were found that met the inclusion criteria. A description and discussion of the driving literature relating to assessment of drivers with dementia relating to the primary objectives is presented.

AUTHORS' CONCLUSIONS

In an area with considerable public health impact for drivers with dementia and other road users, the available literature fails to demonstrate the benefit of driver assessment for either preserving transport mobility or reducing motor vehicle accidents. Driving legislation and recommendations from medical practitioners requires further research that addresses these outcomes in order to provide the best outcomes for both drivers with dementia and the general public.

Validity and reliability of the on-road driving assessment with senior drivers

The on-road driving assessment is widely regarded as the criterion measure for driving performance despite a paucity of evidence concerning its psychometric properties. The purpose of this study was 2-fold. First, we examined the psychometric properties of an on-road driving assessment with 100 senior drivers between 60 and 86 years (80 healthy volunteers and 20 with specific vision deficits) using Rasch modeling. Second, we compared the outcome of the gestalt decision made by trained professionals with that based on weighted error scores from the standardized assessment. Rasch analysis provided good evidence for construct validity and inter-rater reliability of the on-road assessment and some evidence for internal reliability. Goodness of fit statistics for all items were within an acceptable range and the item hierarchy was logical. The test had a moderate reliability index (0.67). The best cut off score yielded sensitivity of 81% and specificity of 95% compared with the gestalt decision. Further research is required with less competent drivers to more fully examine reliability. Healthy senior drivers failed to check blind spots when changing lanes and made errors when asked to report road markings and traffic signs as they drove. In addition unsafe drivers had difficulty negotiating intersections and lane changes.

Health conditions, health symptoms and driving difficulties in older adults

OBJECTIVES

Previous research has indicated that age-related medical or health conditions can affect driving performance in older adults but little, if any, research has examined the mechanisms through which health conditions affect driving difficulties in older adults.

DESIGN

Cross-sectional, correlational study.

SETTING

Random sample from the community. We examined the nature of the relations among health conditions, health-related symptoms, physical fitness levels and specific types of self-reported driving difficulties in a random sample of older adults.

PARTICIPANTS

Three hundred eighteen adults 60 years of age or older.

INTERVENTION

None.

MEASUREMENTS

General health, health-related symptoms, driving-related difficulties and physical activity.

RESULTS

Our findings support the position that health-related symptoms are more clearly associated with driving difficulties than are health conditions, and mediate the relations between health conditions and driving difficulties. Health-related symptoms involving the spine and lower body appeared to be particularly relevant to difficulties with driving experienced in those body areas (i.e. spine and lower body).

CONCLUSION

These findings are encouraging, in that the most frequently reported symptoms are in areas highly amenable to modification and, in that most of our respondents indicated a willingness to engage in exercise if an association between fitness and driving was demonstrated.

Driving abilities in frontotemporal dementia patients

OBJECTIVE

To evaluate driving competency and the relationship between neuropsychiatric symptoms and driving behavior in frontotemporal dementia (FTD) patients.

METHODS

Fifteen patients with a diagnosis of FTD and 15 healthy controls were administered a driving simulation task. Measures of driving performance and neuropsychiatric symptoms were assessed.

RESULTS

The FTD patients received more speeding tickets, ran more stop signs and were involved in more off-road crashes and collisions than the controls. The patients' overall average speed was significantly higher. Driving performance was correlated with agitated behavior.

CONCLUSIONS

Behavioral changes characteristic of FTD patients have an impact on their driving skills leading to inappropriate driving behavior.

Self-regulation of driving and its relationship to driving ability among older adults

Although it is known that older drivers limit their driving, it is not known whether this self-regulation is related to actual driving ability. A sample of 104 older drivers, aged between 60 and 92, completed a questionnaire about driving habits and attitudes. Ninety of these drivers also completed a structured on-road driving test. A measure of self-regulation was derived from drivers' self-reported avoidance of difficult driving situations. The on-road driving test involved a standard assessment used to determine fitness to drive. Driving test scores for the study were based on the number of errors committed in the driving tests, with weightings given according to the seriousness of the errors. The most commonly avoided difficult driving situations, according to responses on the questionnaire, were parallel parking and driving at night in the rain, while the least avoided situation was driving alone. Poorer performance on the driving test was not related to overall avoidance of difficult driving situations. Stronger relationships were found between driving ability and avoidance of specific difficult driving situations. These specific driving situations were the ones in which the drivers had low confidence and that the drivers were most able to avoid if they wished to.