Predicting ability to drive after stroke

Clinical Tests Predicting On-Road Performance in Older Drivers with Cognitive Impairment

Background. The Trail Making Test Part B (Trails B) and Useful Field of View® (UFOV) can predict on-road outcomes in drivers with cognitive impairment (CI); however, studies have not included drivers referred for comprehensive driving evaluations (CDEs), who typically have more severe CI. Purpose. We determined the predictive ability of Trails B and UFOV on pass/fail on-road outcomes in drivers with CI (Montreal Cognitive Assessment <26) referred for CDEs. Method. Retrospective data collection from two driving assessments centers (N  =  100, mean age  =  76.2  ±  8.8 years). Findings. The Trails B (area under the curve [AUC]  =  .70) and UFOV subtests 2 (AUC  =  .73) and 3 (AUC  =  .76) predicted pass/fail outcomes. A cut-point ≥467 ms on UFOV subtest 3 better-predicted pass/fail outcomes with 78.9% sensitivity and 73.5% specificity. In comparison, a cut-point ≥3.58 min on Trails B had lower sensitivity (73.7%) and specificity (61.8%). Implications. The UFOV subtest 3 may be more useful than the Trails B for predicting pass/fail outcomes in drivers with more severe CI referred for CDEs.

Back on the Road: Comparing Cognitive Assessments to Driving Simulators in Moderate to Severe Traumatic Brain Injuries

Objective: To compare established clinical outcome assessments for predicting behind the wheel driving readiness and driving simulator results across age groups and in traumatic brain injury. Methods: Participants included adults who had a traumatic brain injury ranging in age from 31 to 57 years and a non-impaired adult population ranging in age from 18 to 80 years. Physical and cognitive outcomes measures were collected included range of motion and coordination, a “Rules of the Road Test” a “Sign Identification Test,” Trails A and B, and the clock drawing test. Visual measures included the Dynavision D2 system and motor-free visual perceptual test-3 (MVPT-3). Finally, the driving simulators (STIÒ version M300) metro drive assessment was used, which consisted of negotiating several obstacles in a metropolitan area including vehicles abruptly changing lanes, pedestrians crossing streets, and negotiating construction zones. Results: Our findings suggest that the standard paper-pencil cognitive assessments and sign identification test significantly differentiate TBI from a non-impaired population (Trails A, B and Clock drawing test p < 0.001). While the driving simulator did not show as many robust differences with age, the TBI population did have a significantly greater number of road collisions (F3, 78 = 3.5, p = 0.02). We also observed a significant correlation between the cognitive assessments and the simulator variables. Conclusions: Paper-pencil cognitive assessments and the sign identification test highlight greater differences than the STI Driving Simulator between non-impaired and TBI populations. However, the driving simulator may be useful in assessing cognitive ability and training for on the road driving.

Self-awareness predicts fitness to drive among adults referred to occupational therapy evaluation

Background

Driving is associated with independence, well-being, quality of life, and an active lifestyle. Driving requires cognitive, motor, and visual skills, including self-awareness and processing speed. This study examines whether driver self-awareness, motor processing speed, and cognitive processing speed can predict fitness to drive among individuals referred to occupational therapy evaluation due to concerns about their driving ability.

Method

In this cross-sectional study, 39 participants were referred to off- and on-road driving evaluation to determine their fitness to drive due to changes in health status, advanced age, license renewal requirement, or prior automobile accidents. A registered occupational therapist (OT) classified 23 of the participants as fit to drive and 16 as unfit to drive. Motor and cognitive processing speed were assessed by the Stationary Perception-Reaction Timer and the Color Trails Test, respectively. Driving self-awareness was assessed by comparing the DI and OT evaluations to the participants' estimation of their own on-road driving performance.

Results

The fit-to-drive participants had a better motor and cognitive processing speed than those unfit-to-drive. The unfit-to-drive group overestimated their driving ability, whereas the fit-to-drive group accurately or almost accurately estimated their driving ability. Driving self-awareness was a significant predictor of participants' fitness to drive.

Conclusions

This study demonstrates the importance of self-awareness for predicting fitness to drive among people at risk for compromised driving skills. Thus, driving self-awareness should be addressed as part of fitness-to-drive evaluations and interventions.

Development of a Web-Based Mini-Driving Scene Screening Test (MDSST) for Clinical Practice in Driving Rehabilitation

(1) Background: For the elderly and disabled, self-driving is very important for social participation. An understanding of changing driving conditions is essential in order to drive safely. This study aimed to develop a web-based Korean Mini-Driving Scene Screening Test (MDSST) and to verify its reliability and validity for clinical application. (2) Methods: We developed a web-based MDSST, and its content validity was verified by an expert group. The tests were conducted with 102 elderly drivers to verify the internal consistency and reliability of items, and the validity of convergence with the existing Korean-Safe Driving Behavior Measure (K-SDBM) and the Korean-Adelaide Driving Self-Efficacy Scale (K-ADSES) driving tests was also verified. The test–retest reliability was verified using 54 individuals who participated in the initial test. (3) Results: The average content validity index of MDSST was 0.90, and the average internal consistency of all items was 0.822, indicating high content validity and internal consistency. The exploratory factor analysis for construct validity, the KOM value of the data, was 0.658, and Bartlett’s sphericity test also showed a strongly significant result. The four factors were road traffic and signal perception, situation understanding, risk factor recognition, and situation prediction. The explanatory power was reliable at 61.27%. For the convergence validation, MDSST and K-SDBM showed r = 0.435 and K-ADSES showed r = 0.346, showing a moderate correlation. In the evaluation–reevaluation reliability verification, the reliability increased to r = 0.952. (4) Conclusions: The web-based MDSST test developed in this study is a useful tool for detecting and understanding real-world driving situations faced by elderly drivers. It is hoped that the MDSST test can be applied more widely as a driving ability test that can be used in the clinical field of driving rehabilitation.

Social Environmental Factors Related to Resuming Driving after Brain Injury: A Multicenter Retrospective Cohort Study

Many patients resume driving after brain injury regardless of their ability to drive safely. Predictors for resuming driving in terms of actual resumption status and environmental factors are unclear. We evaluated the reasons for resuming driving after brain injury and examined whether social environmental factors are useful predictors of resuming driving. This retrospective cohort study was based on a multicenter questionnaire survey at least 18 months after discharge of brain injury patients with rehabilitation. A total of 206 brain injury patients (cerebrovascular disease and traumatic brain injury) were included in the study, which was conducted according to the International Classification of Functioning (ICF) items using log-binominal regression analysis, evaluating social environmental factors as associated factors of resuming driving after brain injury. Social environmental factors, inadequate public transport (risk ratio (RR), 1.38), and no alternative driver (RR, 1.53) were included as significant independent associated factors. We found that models using ICF categories were effective for investigating factors associated with resuming driving in patients after brain injury and significant association between resuming driving and social environmental factors. Therefore, social environmental factors should be considered when predicting driving resumption in patients after brain injury, which may lead to better counseling and environmental adjustment.

Verification of spatial recognition ability of stroke patients required to resume automobile driving

[Purpose] To help patients who had a stroke resume automobile driving, we evaluated their ability to recognize three-dimensional space like that experienced in actual driving situations, with a focus on sensing car width. [Participants and Methods] Seven patients who had a stroke and 29 healthy adults participated in the study. Three 50-cm-wide chairs and 2 panels, 3 m apart, were placed 9 m from the chair in which the participant sat. One panel was fixed and the other panel could be moved toward the fixed panel in a horizontal direction. The participants were asked to signal when they believed that the width of the chair was the same as the space between the panels. [Results] In the simulation of driving a real car, the mean error in judging distance was 13.2 ± 10.4 cm for the Healthy group and that of the Stroke group was two times greater than that of the Healthy group. [Conclusion] These findings show that spatial recognition cannot be evaluated using paper-based two-dimensional higher brain function tests. To help patients who had a stroke resume driving requires evaluation of three-dimensional spatial recognition ability under circumstances that simulate actual driving situations.

Cognitive and motor deficits contribute to longer braking time in stroke

Background

Braking is a critical determinant of safe driving that depends on the integrity of cognitive and motor processes. Following stroke, both cognitive and motor capabilities are impaired to varying degrees. The current study examines the combined impact of cognitive and motor impairments on braking time in chronic stroke.

Methods

Twenty stroke survivors and 20 aged-matched healthy controls performed cognitive, motor, and simulator driving assessments. Cognitive abilities were assessed with processing speed, divided attention, and selective attention. Motor abilities were assessed with maximum voluntary contraction (MVC) and motor accuracy of the paretic ankle. Driving performance was examined with the braking time in a driving simulator and self-reported driving behavior.

Results

Braking time was 16% longer in the stroke group compared with the control group. The self-reported driving behavior in stroke group was correlated with braking time (r = − 0.53, p = 0.02). The stroke group required significantly longer time for divided and selective attention tasks and showed significant decrease in motor accuracy. Together, selective attention time and motor accuracy contributed to braking time (R² = 0.40, p = 0.01) in stroke survivors.

Conclusions

This study provides novel evidence that decline in selective attention and motor accuracy together contribute to slowed braking in stroke survivors. Driving rehabilitation after stroke may benefit from the assessment and training of attentional and motor skills to improve braking during driving.

Exploring the Predictive Ability of the Motor-Free Visual Perception Test (MVPT) and Trail Making Test (TMT) for On-Road Driving Performance

IMPORTANCE

Resuming driving after a change in functional ability is challenging for patients with a neurological condition. Although a combination of assessment tools has been suggested for use in driving evaluation, resources and availability of tools have been a problem.

OBJECTIVE

To examine the predictive ability of two commonly used tools, the Motor-Free Visual Perception Test (MVPT) and the Trail Making Test, Parts A and B (TMTA and TMTB), on on-road driving performance.

DESIGN

Retrospective chart review of 82 patient charts between 2015 and 2016.

SETTING

Local rehabilitation hospital.

PARTICIPANTS

Eighty-two patients with a primary neurological diagnosis (general neurological condition, n = 13; spinal cord injury, n = 11; stroke, n = 58).

OUTCOMES AND MEASURES

MVPT, TMTA, and TMTB.

RESULTS

Among the patients, 36 passed and 46 failed the on-road evaluation. The TMTA and TMTB scores were significantly different between those who passed or failed the on-road evaluation. Logistic regression analyses revealed that the TMTB completion time was the only significant predictor of on-road driving performance (for the all-patient model, 66% prediction accuracy, -2 log-likelihood [LL] = 93.47, exp β = 0.98; for the stroke-only model, 76% prediction accuracy, -2LL = 59.61, exp β = 0.97).

CONCLUSIONS AND RELEVANCE

Our findings suggest that the TMTB is a better predictor of on-road driving performance for patients with a neurological condition than the MVPT. The findings shed light on the importance of selecting proper tools when assessing driving performance. Future prospective studies with a wider array of predictive variables are recommended to support the present findings.

WHAT THIS ARTICLE ADDS

Occupational therapists should revisit the use of the MVPT in driving assessment and consider multiple assessment tools when evaluating and predicting driving performance.

Relationship Between Line Bisection Test Time and Hemispatial Neglect Prognosis in Patients With Stroke: A Prospective Pilot Study

Objective

To determine the relationship between line bisection test (LBT) performance time and prognosis of hemispatial neglect (HSN) in stroke patients.

Methods

Data on stroke patients with HSN were prospectively collected. After patient recruitment and eligibility screening, the LBT, Motor-Free Visual Perception Test 3rd edition, and Korean version of Mini-Mental State Examination were performed at the time of admission and 4 weeks thereafter. The LBT performance time was also measured. All patients received conventional rehabilitation for 4 weeks. Based on the improvements in their LBT grades, the patients were divided into improved and non-improved groups. The evaluation results of the two groups were compared using Mann–Whitney U-tests and logistic regression was performed to predict the independence of each outcome.

Results

In total, 26 stroke patients with HSN were included, with 13 patients in each group. Significant differences were observed in the baseline LBT performance times between the improved and non-improved groups (p<0.05). Logistic regression analysis revealed associations between HSN prognosis, and baseline LBT performance time (odds ratio=0.95; 95% confidence interval, 0.90–1.00; p<0.05) and baseline Motor-Free Visual Perception Test 3rd edition (odds ratio=1.20; 95% confidence interval, 1.01–1.43; p<0.05).

Conclusion

A significant relationship was observed between the baseline LBT performance time and HSN prognosis.

Cognitive prerequisites for fitness to drive: Norm values for the TMT, UFOV and NorSDSA tests

Background: Fitness-to-drive assessment is a growing area for occupational therapists. There are few off-road tests specially developed to assess fitness to drive, and several cognitive tests have no age-specific norms.Aims/objectives: The aim was to identify and describe age-related norm values for the Trail Making Test, Nordic Stroke Driver Screening Assessment and Useful Field of View test, and to study inter-correlation between test results.Materials and methods: The sample included 410 volunteers; 149 men and 261 women, mean age 52 ± 16.8 years. Commonly used off-road tests were used: TMT A and B, UFOV and NorSDSA.Results: Normative data for the specific subtests and total score for NorSDSA and UFOV are provided and presented in four age groups. Age correlated with the results for most of the subtests.Conclusions: Off-road cognitive test scores are necessary and valuable for occupational therapists in their contribution to the final decision on continued driving. In clinical practice, it can be difficult to interpret cognitive test results when working with driving assessments. Age-based norm values are suggested to be a way to provide clinicians with a benchmark against which scores can be compared.Significance: Age-based norms can guide occupational therapists working with fitness to drive.

Driving after brain injury: Does dual-task modality matter?

BACKGROUND

Virtual reality technology allows neuropsychologists to examine complex, real-world behaviors with high ecological validity and can provide an understanding of the impact of demanding dual-tasks on driving performance.

OBJECTIVE

We hypothesized that a task imposing high cognitive and physical demands (coin-sorting) would result in the greatest reduction in driving maintenance performance.

METHODS

Twenty participants with acquired brain injury and 28 healthy controls were included in the current study. All participants were licensed and drove regularly. Participants completed two standardized VRDS drives: (1) a baseline drive with no distractions, and (2) the same route with three, counterbalanced dual-tasks representing differing demands.

RESULTS

A series of 3 (Task)×2 (Group) ANOVAs revealed that the ABI group tended to go slower than the HC group in the presence of a dual-task, F (1, 111) = 6.24, p = 0.01. Importantly, the ABI group also showed greater variability in speed, F (1, 110) = 10.97, p < 0.01, and lane position, F (1, 108) = 7.81, p < 0.01, an effect driven by dual-tasks with both a cognitive and motor demand.

CONCLUSIONS

These results indicate that long-term driving difficulties following ABI are subtle and likely due to reduced cognitive resources.

Eye Movements Interfere With Limb Motor Control in Stroke Survivors

Background. Humans use voluntary eye movements to actively gather visual information during many activities of daily living, such as driving, walking, and preparing meals. Most stroke survivors have difficulties performing these functional motor tasks, and we recently demonstrated that stroke survivors who require many saccades (rapid eye movements) to plan reaching movements exhibit poor motor performance. However, the nature of this relationship remains unclear. Objective. Here we investigate if saccades interfere with speed and smoothness of reaching movements in stroke survivors, and if excessive saccades are associated with difficulties performing functional tasks. Methods. We used a robotic device and eye tracking to examine reaching and saccades in stroke survivors and age-matched controls who performed the Trail Making Test, a visuomotor task that uses organized patterns of saccades to plan reaching movements. We also used the Stroke Impact Scale to examine difficulties performing functional tasks. Results. Compared with controls, stroke survivors made many saccades during ongoing reaching movements, and most of these saccades closely preceded transient decreases in reaching speed. We also found that the number of saccades that stroke survivors made during ongoing reaching movements was strongly associated with slower reaching speed, decreased reaching smoothness, and greater difficulty performing functional tasks. Conclusions. Our findings indicate that poststroke interference between eye and limb movements may contribute to difficulties performing functional tasks. This suggests that interventions aimed at treating impaired organization of eye movements may improve functional recovery after stroke.

The Trail Making test: a study of its ability to predict falls in the acute neurological in-patient population

Objective:

To determine whether tests of cognitive function and patient-reported outcome measures of motor function can be used to create a machine learning-based predictive tool for falls.

Design:

Prospective cohort study.

Setting:

Tertiary neurological and neurosurgical center.

Subjects:

In all, 337 in-patients receiving neurosurgical, neurological, or neurorehabilitation-based care.

Main Measures:

Binary (Y/N) for falling during the in-patient episode, the Trail Making Test (a measure of attention and executive function) and the Walk-12 (a patient-reported measure of physical function).

Results:

The principal outcome was a fall during the in-patient stay ( n = 54). The Trail test was identified as the best predictor of falls. Moreover, addition of other variables, did not improve the prediction (Wilcoxon signed-rank P < 0.001). Classical linear statistical modeling methods were then compared with more recent machine learning based strategies, for example, random forests, neural networks, support vector machines. The random forest was the best modeling strategy when utilizing just the Trail Making Test data (Wilcoxon signed-rank P < 0.001) with 68% (± 7.7) sensitivity, and 90% (± 2.3) specificity.

Conclusion:

This study identifies a simple yet powerful machine learning (Random Forest) based predictive model for an in-patient neurological population, utilizing a single neuropsychological test of cognitive function, the Trail Making test.

A Case-Control Study Investigating Simulated Driving Errors in Ischemic Stroke and Subarachnoid Hemorrhage

Background

Stroke can affect a variety of cognitive, perceptual, and motor abilities that are important for safe driving. Results of studies assessing post-stroke driving ability are quite variable in the areas and degree of driving impairment among patients. This highlights the need to consider clinical characteristics, including stroke subtype, when assessing driving performance.

Methods

We compared the simulated driving performance of 30 chronic stroke patients (>3 months), including 15 patients with ischemic stroke (IS) and 15 patients with subarachnoid hemorrhage (SAH), and 20 age-matched controls. A preliminary analysis was performed, subdividing IS patients into right (n = 8) and left (n = 6) hemispheric lesions and SAH patients into middle cerebral artery (MCA, n = 5) and anterior communicating artery (n = 6) territory. A secondary analysis was conducted to investigate the cognitive correlates of driving.

Results

Nine patients (30%) exhibited impaired simulated driving performance, including four patients with IS (26.7%) and five patients with SAH (33.3%). Both patients with IS (2.3 vs. 0.3, U = 76, p < 0.05) and SAH (1.5 vs. 0.3, U = 45, p < 0.001) exhibited difficulty with lane maintenance (% distance out of lane) compared to controls. In addition, patients with IS exhibited difficulty with speed maintenance (% distance over speed limit; 8.9 vs. 4.1, U = 81, p < 0.05), whereas SAH patients exhibited difficulty with turning performance (total turning errors; 5.4 vs. 1.6, U = 39.5, p < 0.001). The Trail Making Test (TMT) and Useful Field of View test were significantly associated with lane maintenance among patients with IS (r_s > 0.6, p < 0.05). No cognitive tests showed utility among patients with SAH.

Conclusion

Both IS and SAH exhibited difficulty with lane maintenance. Patients with IS additionally exhibited difficulty with speed maintenance, whereas SAH patients exhibited difficulty with turning performance. Current results support the importance of differentiating between stroke subtypes and considering other important clinical characteristics (e.g., side of lesion, vascular territory) when assessing driving performance and reinforce the importance of physicians discussing driving safety with patients after stroke.

Perceptuo-motor planning during functional reaching after stroke

In healthy young adults, reaching movements are planned such that the initial grasp position on the object is modulated based on the final task goal. This perceptuo-motor coupling has been described as the end-state comfort effect. This study aimed to determine the extent to which visuo-perceptual and motor deficits, but not neglect, due to stroke impact end-state comfort measured as the grasp-height effect. Thirty-four older adults (17 controls, 17 chronic stroke) performed a functional goal-directed two-sequence task with each arm, consisting of reaching and moving a cylindrical object (drain plunger) from an initial to four target platform heights, standardized to body height, in a block randomized sequence. Arm motor impairment (Fugl-Meyer Assessment) and visual–perceptual deficits (Motor-Free Visual Perception Test) were assessed in stroke subjects, and arm and trunk kinematics were assessed in all subjects. The primary outcome measure of the grasp-height effect was the relationship between the grasp heights used at the home position and the final target platform heights. Mixed model analysis was used for data analysis. The grasp-height effect was present in all participants, but decreased in stroke subjects with visuo-perceptual impairments compared to controls. In stroke subjects with sensorimotor impairments alone, indicated by altered kinematics, the grasp-height effect was comparable to controls. This first study examining the grasp-height effect in individuals with stroke provides new knowledge of the impact of visuo-perceptual deficits on movement planning and execution, which may assist clinicians in selecting more effective treatment strategies to improve perceptuo-motor skills and enhance motor recovery.

Using Serial Trichotomization With Common Cognitive Tests to Screen for Fitness to Drive

OBJECTIVE

The aim of this study was to illustrate the use of serial trichotomization with five common tests of cognition to achieve greater precision in screening for fitness to drive.

METHOD

We collected data (using the Montreal Cognitive Assessment, Motor-Free Visual Perception Test, Clock-Drawing Test, Trail Making Test Part A and B [Trails B], and an on-road driving test) from 83 people referred for a driving evaluation. We identified cutpoints for 100% sensitivity and specificity for each test; the driving test was the gold standard. Using serial trichotomization, we classified drivers as either "Pass," "Fail," or "Indeterminate."

RESULTS

Trails B had the best sensitivity and specificity (66.3% of participants correctly classified). After applying serial trichotomization, we correctly identified the driving test outcome for 78.3% of participants.

CONCLUSION

A screening strategy using serial trichotomization of multiple test results may reduce uncertainty about fitness to drive.

Neuropsychological Assessment of Driving Capacity

Clinicians are increasingly requested to make determinations regarding patients' driving capacity in the context of neurological injury/conditions and a growing cohort of older drivers. The capability to drive safely involves a number of cognitive, physical, and sensorimotor abilities that may be impacted by injury, illness, or substances that influence alertness. Neuropsychological measures are an important component of a multidisciplinary approach for evaluation of driving capacity. Clinicians should become familiar with measures that have the best predictive validity so they may incorporate a patient's neurocognitive strengths and weaknesses in decisions about driving ability.

Prediction of Driving after Stroke: A Prospective Study

The process of determining whether patients with stroke should drive again often involves off-road evaluations and road tests that usually take about 2 to 3 h to complete. Objectives. This prospective study sought to identify the combination of tests that best predicts fitness to drive after stroke. The main aim was to develop a short and predictive predriving assessment battery. Methods. Sixty-eight consecutive stroke patients were studied who performed a mandatory predriving assessment at the Belgian Road Safety Institute, Brussels, within 18 months. Performance in a predriving assessment included medical examination (when needed), visual and neuropsychological evaluations, and an on-road test. Based on these assessments, a physician, psychologist, and the driving safety expert who administered the tests decided if a subject was either “fit to drive,”“temporarily unfit to drive,” or “unfit to drive.” Results. Logistic regression analysis revealed a combination of visual neglect, figure of Rey, and on-road tests as the model that best predicted ( R2 = 0.73) fitness to drive after stroke. Using a discriminant function that included the 3 tests of the logistic model, the fitness to drive judgments of 59 (86.8%) subjects were correctly predicted. The sensitivity and specificity of the predictions were 79.4% and 94.1%, respectively. Conclusion. Fitness to drive after stroke can be predicted from performance on a few road-related tests with a high degree of accuracy. However, some individuals require extended assessments and further tests.

Cognitive Performance, Driving Behavior, and Attitudes over Time in Older Adults

Nous avons théorisé que les changements au fil du temps dans les performances cognitives sont associés à des changements dans les perceptions, les attitudes et les comportements d’auto-régulation des personnes âgées qui conduisent. Les adultes âgés en bonne santé (n = 928) ont subi les évaluations cognitives au début avec deux suivis annuels subséquents, et ils ont rempli des formulaires avec des échelles qui mesurent leurs perceptions, les attitudes et les comportements de conduite. L’analyse multivariée montre des petites relations, mais statistiquement significatives, entre les tests cognitifs et les mesures qui ont été auto-déclarée, les plus grandes amplitudes entre les scores étant sur les sentiers B tâche cognitive (secondes), la perception de la capacité de conduire (β = 0,32), et l’évasion des situations de conduite (β = 0,55) (p <0,05). Selon cette analyse exploratoire, le ralentissement cognitif et le dysfonctionnement exécutif semblent être associés aux capacités à conduire perçues d'être modestement inférieurs et à l’évitement accru des situations de conduite au fil du temps.

The influence of a concurrent cognitive task on lower limb reaction time among stroke survivors with right- or left-hemiplegia

OBJECTIVE

To determine the impact of cognitive interference on foot pedal reaction time among stroke survivors with right- (RH) or left-hemiplegia (LH).

DESIGN

Cross-sectional comparison without randomization.

SUBJECTS/PATIENTS

10 patients post-stroke with RH, 10 with LH; 10 age-matched controls.

METHODS

Foot pedal response times were measured using three different reaction time (RT) paradigms: simple RT, dual-task RT (counting backward by serial 3 seconds), and choice RT (correct response contingent on stimuli to eliminate pre-programing). RH and LH used the non-paretic leg for all trials. Three 3 (RT task) × 3 (group) mixed-model factorial ANOVAs were used to compare RT, movement time (MT), total response time (TRT).

RESULTS

Overall controls demonstrated faster RT than RH (332 ± 73 versus 474 ± 144 ms, P < 0.001) or LH (402 ± 127 ms, P < 0.05); LH group demonstrated faster RT than those with RH (P < 0.05). Control subjects demonstrated significantly faster RT than RH for all RT conditions (P < 0.05 for all). In contrast, controls achieved significantly faster RT than LH for the choice RT condition only (P < 0.05), but not for the simple (P = 0.12) or dual-task RT conditions (P = 0.25).

CONCLUSIONS

Compared to controls, response time was significantly impaired among LH and RH when the response could not be pre-programmed. While current simple RT testing commonly employed by driver rehab specialists may be sufficient for detecting RT deficits in patients with RH, simple or dual-task RT tests alone may fail to detect RT deficiencies among LH, even when testing the non-paretic limb. Choice RT should be added to post-stroke driver fitness assessment, particularly for patients with LH.

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.

Factors Influencing the Clinical Stratification of Suitability to Drive after Stroke: A Qualitative Study

While a clinical pre-selection screening process for a stroke patient's suitability for driving has been acknowledged, little is known about the factors or processes influencing this screening typically conducted by clinicians practicing at a generalist level. This study explored this clinical stratification process through the use of semi-structured interviews with senior occupational therapists (n = 17) and stroke physicians (n = 7) using qualitative description methodology. The findings revealed a trichotomy stratification of stroke patients for driving in the clinical setting; those who are fit to drive, unfit to drive, and a "maybe" group who need more detailed assessment and observation. Factors that had a major influence on this clinical-based stratification of driving suitability were client's levels of awareness, insight, and impulsivity. A period of prolonged contact with the client was preferential to guide the stratification decision in order for clinicians to build a comprehensive picture of the person. A mix of assessment approaches including standardized assessment but with increased emphasis on naturalistic observation of functional performance underpinned the clinical stratification process. This study uncovers some of the factors and processes influencing the early clinical-based stratification of driving suitability after stroke, and highlights the contribution of the generalist practitioner in the assessment of fitness to drive continuum.

A randomized clinical trial to determine effectiveness of driving simulator retraining on the driving performance of clients with neurological impairment

Introduction

Following a neurological event, returning to driving is an important activity contributing to improved participation within the community. The purpose of this study was to examine the effectiveness of driving simulator retraining on driving in clients with neurological impairment and to examine factors associated with treatment effectiveness.

Method

Individuals with non-degenerative brain injury were randomized to either a simulator training or control group. The simulator group received individualized training (16 sessions) using a driving simulator. The control group did not receive intervention. A blind evaluator assessed participants on the DriveAble On-Road Driving Evaluation.

Results

There was no significant difference between groups in the proportion of individuals who passed the driving evaluation (Chi2 = 0.65; p = 0.42; CI = −0.41 to +0.17). However, participants with moderate impairment who received simulator training were more likely to pass the driving test compared with those in the control group (86% versus 17%; Chi2 = 6.2; p = 0.03; CI = −1.00 to −0.30). There were no differences in pass rate according to diagnosis, gender, or for those with severe impairments.

Conclusion

Results provide clinicians with preliminary information on the potential clinical usefulness of driving simulator training. While the findings do not support simulator retraining for the group as a whole, they suggest that clients with moderate impairment have the potential to benefit.

Predictive validity of the Montreal Cognitive Assessment (MoCA) as a screening tool for on-road driving performance

Introduction

The objectives of this study are to determine (1) the ability of the Montreal Cognitive Assessment to predict on-road driving performance in drivers with a neurological condition and elderly drivers with suspected cognitive decline, and (2) the association between the performance on the Useful Field of View and the performance on the Montreal Cognitive Assessment.

Method

This study used a retrospective design. Clients were included who had completed the Montreal Cognitive Assessment and the on-road driving evaluation from November 2006 to May 2009 ( n = 154) in a driving rehabilitation program in the Montreal Area. Total scores on the Montreal Cognitive Assessment, Useful Field of View risk categories, pass or fail outcomes from an on-road evaluation, as well as demographic and clinical characteristics were recorded from participants’ medical charts.

Results

The Montreal Cognitive Assessment was found to have a sensitivity of 84.5% and a specificity of 50% with a cut-off of ≤25. It was significantly associated with the Useful Field of View risk category.

Conclusion

The Montreal Cognitive Assessment could be a valuable screening tool. However, its predictive validity is not strong enough to recommend its use as the sole instrument for identifying unfit drivers.

Determining fitness to drive: A systematic review of the methods and assessments used after mild traumatic brain injury

Introduction

Limited evidence is available to support knowledge of the time-frame and capacity for fitness to drive after mild traumatic brain injury. The aim of this systematic review was to identify what methods and assessments are, or could be used to determine fitness to drive for this population.

Method

We undertook a systematic search of six electronic databases. Two authors rated all studies for methodological content and quality, and standardised data were extracted. Narrative analysis was conducted to understand the content of eligible studies.

Findings

A total of 2022 articles were retrieved; seven articles met the inclusion criteria. Self-reported questionnaires, non-standardised assessments, questionnaires completed by next-of-kin, and simulator tests were the primary methods used to determine fitness to drive. Only one assessment has been used to aid recommendations about fitness to drive in the acute hospital setting. Six additional standardised assessments were identified that have the potential to predict fitness to drive in this population group; however, these assessments require further psychometric testing prior to use.

Conclusion

While a variety of methods and assessments are currently used, there is little research evidence to suggest when individuals are able to return to driving after mild traumatic brain injury. Research is urgently required to determine a consistent and standardised approach to assessing fitness to drive following mild traumatic brain injury.

Predictors of Driving Ability Following Stroke: A Systematic Review

BACKGROUND AND PURPOSE

The objective of this review is to identify the most consistent predictors of driving ability post stroke.

METHOD

A computerized search of numerous databases from 1966 forward was completed. Measured outcomes included voluntary driving cessation or results of on-road driving evaluation. Studies were evaluated using the Newcastle-Ottawa Quality Assessment Scale.

RESULTS

17 eligible studies were identified. The most useful screening tests were tests assessing cognitive abilities. These included the Trail Making A and B tests, the Rey-Osterreith Complex Figure Design, and the Useful Field of View Test.

CONCLUSION

Cognitive tests that assess multiple cognitive domains relevant to driving appear to have the best reproducibility in predicting fitness to drive in stroke patients.

The trail making test as a screening instrument for driving performance in older drivers; a translational research

BACKGROUND

In many countries, primary care physicians determine whether or not older drivers are fit to drive. Little, however, is known regarding the effects of cognitive decline on driving performance and the means to detect it. This study explores to what extent the trail making test (TMT) can provide indications to clinicians about their older patients' on-road driving performance in the context of cognitive decline.

METHODS

This translational study was nested within a cohort study and an exploratory psychophysics study. The target population of interest was constituted of older drivers in the absence of important cognitive or physical disorders. We therefore recruited and tested 404 home-dwelling drivers, aged 70 years or more and in possession of valid drivers' licenses, who volunteered to participate in a driving refresher course. Forty-five drivers also agreed to undergo further testing at our lab. On-road driving performance was evaluated by instructors during a 45 minute validated open-road circuit. Drivers were classified as either being excellent, good, moderate, or poor depending on their score on a standardized evaluation of on-road driving performance.

RESULTS

The area under the receiver operator curve for detecting poorly performing drivers was 0.668 (CI95% 0.558 to 0.778) for the TMT-A, and 0.662 (CI95% 0.542 to 0.783) for the TMT-B. TMT was related to contrast sensitivity, motion direction, orientation discrimination, working memory, verbal fluency, and literacy. Older patients with a TMT-A ≥ 54 seconds or a TMT-B ≥ 150 seconds have a threefold (CI95% 1.3 to 7.0) increased risk of performing poorly during the on-road evaluation. TMT had a sensitivity of 63.6%, a specificity of 64.9%, a positive predictive value of 9.5%, and a negative predictive value of 96.9%.

CONCLUSION

In screening settings, the TMT would have clinicians uselessly consider driving cessation in nine drivers out of ten. Given the important negative impact this could have on older drivers, this study confirms the TMT not to be specific enough for clinicians to justify driving cessation without complementary investigations on driving behaviors.

Characteristics of visual-perceptual function measured by the motor-free visual perception test-3 in korean adults

OBJECTIVE

To adapt and standardize the Motor-Free Visual Perception Test-3 (MVPT-3) to Koreans and investigate the change in visual-perceptual function using the MVPT-3 in healthy Korean adults.

METHODS

The Korean version of the MVPT-3 was developed through a cross-cultural adaptation process according to 6 steps, including translation, reconciliation, back translation, cognitive debriefing, feedback, and final reconciliation. A total of 321 healthy Korean volunteers (mean age, 51.05 years) were recruited. We collected participant demographic data, such as sex, age, and years of education, and performed the Korean version of the Mini-Mental State Examination (K-MMSE) and MVPT-3. Internal consistency of the MVPT-3 and the relationships between demographic data, K-MMSE and MVPT-3 scores were analyzed. The results of this study were compared with published data from western countries including the United States and Canada.

RESULTS

Total score on the MVPT-3 was positively correlated with years of education (r=0.715, p<0.001) and K-MMSE score (r=0.718, p<0.001). However, it had a negative correlation with age (r=-0.669, p<0.001). A post-hoc analysis of MVPT-3 scores classified age into 5 groups of ≤49, 50-59, 60-69, 70-79, ≥80 years and years of education into 4 groups of 0, 1-9, 10-12, ≥13 years. No significant differences in MVPT-3 scores were observed according to sex or country.

CONCLUSION

Visual perception was significantly influenced by age, years of education, and cognitive function. Reference values for the MVPT-3 provided in this study will be useful for evaluating and planning a rehabilitation program of visual perceptual function in patients with brain disorders.

Driving with binocular visual field loss? A study on a supervised on-road parcours with simultaneous eye and head tracking

Post-chiasmal visual pathway lesions and glaucomatous optic neuropathy cause binocular visual field defects (VFDs) that may critically interfere with quality of life and driving licensure. The aims of this study were (i) to assess the on-road driving performance of patients suffering from binocular visual field loss using a dual-brake vehicle, and (ii) to investigate the related compensatory mechanisms. A driving instructor, blinded to the participants' diagnosis, rated the driving performance (passed/failed) of ten patients with homonymous visual field defects (HP), including four patients with right (HR) and six patients with left homonymous visual field defects (HL), ten glaucoma patients (GP), and twenty age and gender-related ophthalmologically healthy control subjects (C) during a 40-minute driving task on a pre-specified public on-road parcours. In order to investigate the subjects' visual exploration ability, eye movements were recorded by means of a mobile eye tracker. Two additional cameras were used to monitor the driving scene and record head and shoulder movements. Thus this study is novel as a quantitative assessment of eye movements and an additional evaluation of head and shoulder was performed. Six out of ten HP and four out of ten GP were rated as fit to drive by the driving instructor, despite their binocular visual field loss. Three out of 20 control subjects failed the on-road assessment. The extent of the visual field defect was of minor importance with regard to the driving performance. The site of the homonymous visual field defect (HVFD) critically interfered with the driving ability: all failed HP subjects suffered from left homonymous visual field loss (HL) due to right hemispheric lesions. Patients who failed the driving assessment had mainly difficulties with lane keeping and gap judgment ability. Patients who passed the test displayed different exploration patterns than those who failed. Patients who passed focused longer on the central area of the visual field than patients who failed the test. In addition, patients who passed the test performed more glances towards the area of their visual field defect. In conclusion, our findings support the hypothesis that the extent of visual field per se cannot predict driving fitness, because some patients with HVFDs and advanced glaucoma can compensate for their deficit by effective visual scanning. Head movements appeared to be superior to eye and shoulder movements in predicting the outcome of the driving test under the present study scenario.

The relationship between cognitive performance, perceptions of driving comfort and abilities, and self-reported driving restrictions among healthy older drivers

The objective of the present study was to examine the relationship between cognitive performance, driver perceptions and self-reported driving restrictions. A cross-sectional analysis was conducted on baseline data from Candrive II, a five-year prospective cohort study of 928 older drivers aged 70-94 years from seven cities. Cognitive performance was assessed using the Montreal Cognitive Assessment (MoCA) as well as the Trail Making Test, parts A and B. Driver perceptions were assessed using the Day and Night Driving Comfort Scales and the Perceived Driving Abilities scale, while driving practices were captured by the Situational Driving Frequency and Avoidance scales, as well as the Driving Habits and Intentions Questionnaire. The baseline data indicates this cohort is largely a cognitively intact group. Univariate regression analysis showed that longer Trails A and B completion times were significantly, but only modestly associated with reduced driving frequency and perceived driving abilities and comfort, as well as a significant tendency to avoid more difficult driving situations (all p<.05). Most of these associations persisted after adjusting for age and sex, as well as indicators of health, vision, mood and physical functioning. Exceptions were Trails A and B completion times and situational driving frequency, as well as time to complete Trails B and current driving restrictions. After adjusting for the confounding factors, the total MoCA score was not associated with any of the driving measure scores while the number of errors on Trails A was significantly associated only with situational driving frequency and number of errors on Trails B was significantly associated only with situational driving avoidance. Prospective follow-up will permit examination of whether baseline cognition or changes in cognition are associated with changes in driver perceptions, actual driving restrictions and on-road driving outcomes (e.g., crashes, violations) over time.

It is premature to test older drivers with the SIMARD-MD

BACKGROUND

A new tool, the SIMARD-MD, has been proposed to help physicians identify cognitively impaired drivers who may be unfit to drive, but little empirical evidence is available to justify its use. We analyzed data from a cohort of older Canadian drivers who had undergone cognitive testing to: (1) correlate the SIMARD-MD with other tools that measure cognition (e.g., trail-making test), (2) identify how many drivers, using published cut-offs on the SIMARD-MD, would be recommended to lose their license, or be considered fit to drive, or be required to undergo further driving assessment, and (3) determine if the SIMARD-MD is biased by level of education as many cognitive tools are.

METHODS

Cross-sectional data from 841 drivers aged 70 and over from seven Canadian sites who are enrolled in a 5-year cohort study were used for the analyses. Scores on the SIMARD-MD were correlated with scores on the other cognitive measures. The recommendations that would be made based on the SIMARD-MD scores were based on published cut-off values suggested by the authors of the tool. The impact of education status was examined using linear regression controlling for age.

RESULTS

Correlations between the SIMARD-MD and other cognitive measures ranged from .15 to .86. Using published cut-off scores, 21 participants (2.5%) would have been recommended to relinquish their licenses, 428 (50.9%) would have been deemed fit to drive, and 392 (46.6%) would have been required to undergo further testing. We found a difference of 8.19 points (95% CI=4.99, 11.40, p<.001) in favor of drivers with post-secondary education versus those without, representing over 11% of the mean score.

DISCUSSION

The SIMARD-MD is unlikely to be valuable to clinicians because it lacks sufficient precision to provide clear recommendations about fitness-to-drive. Recommendations based solely on the SIMARD-MD may place many seniors at risk of losing their transportation mobility or incurring unnecessary stress and costs to prove they are safe to drive. Furthermore, the education bias may create an unwanted structural inequity. Hence, adoption of the SIMARD-MD as a tool to determine fitness-to-drive appears premature.

Comparison of foot pedal reaction time among patients with right or left hemiplegia and able-bodied controls

BACKGROUND

Although inpatient stroke rehabilitation provides clinicians with the opportunity to prepare patients for continuation of prestroke activities, little is known about the patients' ability to safely resume driving at the point of discharge to the community.

OBJECTIVE

To compare foot pedal response times of 20 stroke patients with right hemiplegia (RH) or left hemiplegia (LH) and 10 controls.

METHODS

A cross-sectional design was used. Response times were measured using 3 foot pedal operation techniques: (1) right-sided accelerator with right leg operating accelerator and brake, (2) right-sided accelerator with left leg operating accelerator and brake, and (3) left-sided accelerator with left leg operating accelerator and brake. Outcomes included reaction time (RT), movement time (MT), and total response time (TRT).

RESULTS

Controls demonstrated faster RT than patients with RH (263 vs 348 ms; P < .001) or LH (316 ms; P < .05) for all conditions, as well as faster MT than patients with RH (P < .05 for all) but not LH when using the right leg (258 vs 251 ms; P = .82). Controls demonstrated faster TRT than patients with RH (P < .001 for all) but not LH when using the right leg (515 vs 553 ms; P = .44).

CONCLUSIONS

When using the nonparetic leg, patients with LH had braking response times comparable to controls, but patients with RH demonstrated significant impairment of both the paretic and nonparetic legs.

Systematic review of the evidence for Trails B cut-off scores in assessing fitness-to-drive

Background

Fitness-to-drive guidelines recommend employing the Trail Making B Test (a.k.a. Trails B), but do not provide guidance regarding cut-off scores. There is ongoing debate regarding the optimal cut-off score on the Trails B test.

The objective of this study was to address this controversy by systematically reviewing the evidence for specific Trails B cut-off scores (e.g., cut-offs in both time to completion and number of errors) with respect to fitness-to-drive.

Methods

Systematic review of all prospective cohort, retrospective cohort, case-control, correlation, and cross-sectional studies reporting the ability of the Trails B to predict driving safety that were published in English-language, peer-reviewed journals.

Results

Forty-seven articles were reviewed. None of the articles justified sample sizes via formal calculations. Cut-off scores reported based on research include: 90 seconds, 133 seconds, 147 seconds, 180 seconds, and < 3 errors.

Conclusions

There is support for the previously published Trails B cut-offs of 3 minutes or 3 errors (the ‘3 or 3 rule’). Major methodological limitations of this body of research were uncovered including (1) lack of justification of sample size leaving studies open to Type II error (i.e., false negative findings), and (2) excessive focus on associations rather than clinically useful cut-off scores.

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.

The neural correlates of impaired collision avoidance in hemianopic patients

PURPOSE

The aim of this study was to assess the brain regions associated with impaired performance in a virtual, dynamic collision avoidance task, in a group of patients with homonymous visual field defects (HVFDs) because of unilateral vascular brain lesions.

METHODS

Overall task performance was quantitatively assessed as the number of collisions while crossing an intersection at two levels of traffic density. Twenty-six patients were divided into two subgroups using the median split method: patients with 'performance above average' (HVFD(A), i.e. lower number of collisions) and patients with 'performance below average' (HVFD(B), i.e. higher number of collisions). In order to identify the anatomical structures that might be specifically affected in HVFD(B) patients but spared in HVFD(A) patients, overlap, subtraction and voxel-based lesion-symptom mapping analyses were performed using the MRIcron software.

RESULTS

No significant difference in collision avoidance between patients with left- and right-hemispheric lesions was revealed. Separate lesion analysis in 12 patients with right- and 14 patients with left-hemispheric lesions showed that the cortical structures associated with impaired collision avoidance were the parieto-occipital region and posterior cingulate gyrus in the right hemisphere and the inferior occipital cortex and parts of the fusiform (occipito-temporal) gyrus in the left hemisphere.

CONCLUSION

In the present collision avoidance paradigm, impaired performance of patients with right-hemispheric lesions is associated with damage in the dorsal processing stream and potential impact on the visual spatial working memory (WM), while impaired performance of patients with left-hemispheric lesions is associated with damage in the ventral stream and potential impact on the visual object WM.

Mathematical Model to Predict Drivers’ Reaction Speeds

Mental distractions and physical impairments can increase the risk of accidents by affecting a driver’s ability to control the vehicle. In this article, we developed a linear mathematical model that can be used to quantitatively predict drivers’ performance over a variety of possible driving conditions. Predictions were not limited only to conditions tested, but also included linear combinations of these tests conditions. Two groups of 12 participants were evaluated using a custom drivers’ reaction speed testing device to evaluate the effect of cell phone talking, texting, and a fixed knee brace on the components of drivers’ reaction speed. Cognitive reaction time was found to increase by 24% for cell phone talking and 74% for texting. The fixed knee brace increased musculoskeletal reaction time by 24%. These experimental data were used to develop a mathematical model to predict reaction speed for an untested condition, talking on a cell phone with a fixed knee brace. The model was verified by comparing the predicted reaction speed to measured experimental values from an independent test. The model predicted full braking time within 3% of the measured value. Although only a few influential conditions were evaluated, we present a general approach that can be expanded to include other types of distractions, impairments, and environmental conditions.

Retrospective cohort study of accident outcomes for individuals who have successfully undergone driver assessment following stroke

BACKGROUND

The occupational role of 'driver' is highly valued. Stroke can have a significant impact on an individual's ability to drive safely. Multi-disciplinary driver assessments are conducted to assess the safety of post-stroke individuals returning to driving, however, little follow-up of drivers following successful assessment has been performed.

AIM

The objective of this study was to investigate whether passing a multi-disciplinary driving assessment following stroke predicted medium- to long-term safe and confident driving.

METHODS

A retrospective cohort study with primary data collection through structured telephone interviews was undertaken. Respondents were individuals post-stroke aged 18-74years who had successfully passed a multi-disciplinary driver assessment.

RESULTS

 Forty-five respondents were interviewed an average of 20months following the assessment. Forty individuals were still driving. Twenty-five driving respondents reported driving in conditions that indicated confident driving. Confident driving was measured by driving frequency and distance, night driving, freeway driving and driving alone. The frequency of accidents and incidents suggests that 95% (n=38) of drivers are 'safe'. Eight respondents reported accidents, one of which was major. In two accidents the respondent was 'at fault'. A crash rate of 222 per 100,000 drivers is within the confidence interval for similar accidents in New South Wales.

CONCLUSIONS

The results of this small cohort study suggest that a multi-disciplinary driver assessment may be effective in identifying people following stroke with the ability to drive safely and confidently.

Assessing executive function in relation to fitness to drive: a review of tools and their ability to predict safe driving

BACKGROUND/AIM

The assessment of executive functions is an integral component in determining fitness to drive. A structured review was conducted to identify assessment tools used to measure executive function in relation to driving and to describe these tools according to: (i) specific executive function components assessed; (ii) the tool's validity in predicting safe driving; and (iii) clinical utility.

METHODS

Sixty-nine articles were reviewed, identifying 53 executive function tools/assessments used in driving research. Each tool was critically appraised and the findings were compiled in a Driving Executive Function Tool Guide.

RESULTS

Among the 53 tools, there were 27 general assessments of cognition, 19 driving-specific and seven activities of daily living/instrumental activities of daily living assessments. No single tool measured all executive function components: working memory was the most common (n = 20/53). Several tools demonstrated strong predictive validity and clinical utility. For example, tools, such as the Trail Making Test and the Maze Task, have the shortest administration time (i.e. often less than 10 minutes) and the most easily accessible method of administration (i.e. pen and paper or verbal). Driving-specific tools range from short questionnaires, such as the 10-minute Manchester Driving Behaviour Questionnaire, to more complex tools requiring about 45 minutes to administer. CONCLUSIONS AND SIGNIFICANCE OF THE STUDY: The appropriateness of a tool depends on the individual being assessed and on practical constraints of the clinical context. The Driving Executive Function Tool Guide provides useful information that should facilitate decision-making and selection of appropriate executive function tools in relation to driving.

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".

Neuropsychological assessment of fitness to drive following acquired cognitive impairment

PRIMARY OBJECTIVE

The study evaluated a neuropsychological assessment battery used to assess fitness to drive in cognitively impaired individuals and hypothesized that the battery would be associated with on-road outcome measures. A secondary aim was to explore the relationships between individual neuropsychological tests and driving performance.

RESEARCH DESIGN

The study used a cross-sectional design in which a sample of individuals with various types of cognitive impairment completed the test battery and an on-road driving test.

METHODS AND PROCEDURES

Performance on the test battery was compared to on-road driving performance in 104 individuals with acquired cognitive impairment.

MAIN OUTCOMES AND RESULTS

The battery had 73% sensitivity and 76% specificity in terms of agreement with the 'pass/fail' classification of the on-road driving test. Scores on the battery accounted for 18% of the variance in the total number of corrective interventions performed by a driving instructor during the on-road test. Most tests correlated significantly with driving test outcomes. While one test, the Rey Complex Figure Test, emerged as an independent predictor of driving performance in multiple regression analyses, the variance explained by this single test was small.

CONCLUSIONS

The results provide support for the use of a battery approach to assess fitness to drive.