Older adult driving performance assessed under simulated and on-road conditions.

Simulated driving offers a convenient test of driving ability for older drivers, although the viability of using simulated driving with this population is mixed. The relative weighting of the relevant perceptual, cognitive, and physical factors may vary between simulated and on-road driving. The current study was designed to assess this possibility. We conducted simulated and on-road driving tests of 61 older adults aged 66-92 years. To ensure that the driving performance was measured similarly between the two driving modalities, we employed the Record of Driving Errors (RODE) driving assessment system during both driving tests. Correlation and random weights analysis (RWA) results indicated only modest evidence of correspondence between the simulated and on-road driving performances. The primary factors operative in both simulated and on-road driving was Useful Field of View and a measure of basic cognition. Unique factors for simulated driving included a measure of physical mobility (Time-Up-and-Go) and spatial reasoning (Line), and for on-road driving included chronological age and sensorimotor processing (Trail-Making Task A). Chronological age was correlated primarily the on-road rather than simulated test, was greatly reduced with the inclusion of additional explanatory factors, and likely reflects driving efficiency rather than driving safety. We conclude that simulated driving in healthy older drivers can be beneficial for research purposes to assess cognitive and perceptual factors that underly driving effectiveness, although it cannot serve as a clear proxy for on-road driving.

Using Implementation Science to Guide the Process of Adapting a Patient Engagement Intervention for Inpatient Spinal Cord Injury/Disorder Rehabilitation.

OBJECTIVES: This study aimed to describe the process of adapting an evidence-based patient engagement intervention, enhanced medical rehabilitation (E-MR), for inpatient spinal cord injury/disease (SCI/D) rehabilitation using an implementation science framework. DESIGN: We applied the collaborative intervention planning framework and included a community advisory board (CAB) in an intervention mapping process. SETTING: A rehabilitation hospital. PARTICIPANTS: Stakeholders from inpatient SCI/D rehabilitation (N=7) serving as a CAB and working with the research team (N=7) to co-adapt E-MR. INTERVENTIONS: E-MR. MAIN OUTCOME MEASURES: Logic model and matrices of change used in CAB meetings to identify areas of intervention adaptation. RESULTS: The CAB and research team implemented adaptations to E-MR, including (1) identifying factors influencing patient engagement in SCI/D rehabilitation (eg, therapist training); (2) revising intervention materials to meet SCI/D rehabilitation needs (eg, modified personal goals interview and therapy trackers to match SCI needs); (3) incorporating E-MR into the rehabilitation hospital's operations (eg, research team coordinated with CAB to store therapy trackers in the hospital system); and (4) retaining fidelity to the original intervention while best meeting the needs of SCI/D rehabilitation (eg, maintained core E-MR principles while adapting). CONCLUSIONS: This study demonstrated that structured processes guided by an implementation science framework can help researchers and clinicians identify adaptation targets and modify the E-MR program for inpatient SCI/D rehabilitation.

Caregiver Prediction of Driving Fitness in Older Adults with Dementia.

Objectives: To determine whether caregiver opinion of fitness to drive and the level of assistance needed for functional activities are useful in determining the need for a Comprehensive Driving Evaluation.Methods: This study examined a sample (N = 179) of drivers with dementia. Caregivers completed a questionnaire that included caregiver opinion of driving fitness and the Functional Assessment Questionnaire (FAQ). A univariate simple logistic regression model was used to examine the relationship of road test failure with caregiver opinion of driving fitness and FAQ scores. From the significant predictive variables from the univariate test, multiple logictic regression models were used to examine possible combination of variables as predictors of road test failure.Results: The combination of caregiver opinion of driving fitness and the FAQ sub-item for memory were found to have modest ability in predicting failure on a standardized on-road driving assessment (AUC 0.727).Conclusions: Caregiver opinion of driving fitness and most individual higher order activities of daily living were found to be independent predictors of failure on a standardized road test.Clinical Implications: Caregiver opinion of driving fitness and ratings of functional activities may be useful for families and clinicians in considering whether an adult with dementia should be more carefully assessed for fitness to drive.

Validity and Reliability of the Traffic Sign Naming Test (TSNT) and Written Exam for Driving Decisions (WEDD) as Measures of Fitness to Drive Among Older Adults.

IMPORTANCE: Occupational therapists need valid and reliable tools to help determine fitness to drive of older drivers with medical conditions such as dementia. OBJECTIVE: To establish the validity and reliability of the Traffic Sign Naming Test (TSNT) and Written Exam for Driving Decisions (WEDD) as measures of fitness to drive of adults with and without dementia. DESIGN: Cross-sectional. SETTING: Washington University Medical School in St. Louis in collaboration with the Rehabilitation Institute of St. Louis. PARTICIPANTS: Older drivers diagnosed with dementia (n = 130) and without dementia (n = 34). Drivers with dementia required a physician referral indicating a medical need for a driving evaluation, a diagnosis of dementia, and an Alzheimer Detection 8 score of 2. Drivers without dementia were required to be age 55 yr or older and not meet criteria for dementia. OUTCOMES AND MEASURES: Participants completed a comprehensive driving evaluation (CDE) that included clinical measures of vision, motor, and cognition; TSNT; and WEDD. The outcome measure was performance on a standardized on-road assessment. RESULTS: The TSNT's interrater reliability was determined to be strong (κ = .80). The TSNT and WEDD demonstrated convergent validity with cognitive measures (p < .001) and discriminant validity with visual and motor measures in the CDE. The TSNT (area under the curve [AUC] = .74) and WEDD (AUC = .71) had fair ability to predict failure on a standardized on-road assessment. CONCLUSION AND RELEVANCE: TSNT and WEDD are recommended for use by occupational therapists in combination with other performance measures when determining fitness to drive or need for a CDE. WHAT THIS ARTICLE ADDS: The TSNT and WEDD can be included as screening tools (in addition to other performance measures) to assist clinicians in determining which clients need to be referred for a CDE. The TSNT and WEDD can also be included as part of a CDE to assist driving rehabilitation specialists in making final recommendations regarding fitness to drive. The scores generated from the TSNT and WEDD address driving knowledge in a way that may be more understandable to clients and more relatable to skills needed to actually drive.

Alzheimer Disease Biomarkers and Driving in Clinically Normal Older Adults: Role of Spatial Navigation Abilities.

PURPOSE: Older adults experience impaired driving performance, and modify their driving habits, including limiting amount and spatial extent of travel. Alzheimer disease (AD)-related pathology, as well as spatial navigation difficulties, may influence driving performance and driving behaviors in clinically normal older adults. We examined whether AD biomarkers [cerebrospinal fluid (CSF) concentrations of Aß42, tau, and ptau181] were associated with lower self-reported spatial navigation abilities, and whether navigation abilities mediated the relationship of AD biomarkers with driving performance and extent. METHODS: Clinically normal older adults (n=112; aged 65+) completed an on-road driving test, the Santa Barbara Sense of Direction scale (self-report measure of spatial navigation ability), and the Driving Habits Questionnaire for an estimate of driving extent (composite of driving exposure and driving space). All participants had a lumbar puncture to obtain CSF. RESULTS: CSF Aß42, but not tau or ptau181, was associated with self-reported navigation ability. Lower self-reported navigation was associated with reduced driving extent, but not driving errors. Self-reported navigation mediated the relationship between CSF Aß42 and driving extent. CONCLUSIONS: Findings suggest that cerebral amyloid deposition is associated with lower perceived ability to navigate the environment, which may lead older adults with AD pathology to limit their driving extent.

Preclinical Alzheimer's disease and longitudinal driving decline.

INTRODUCTION: Links between preclinical AD and driving difficulty onset would support the use of driving performance as an outcome in primary and secondary prevention trials among older adults (OAs). We examined whether AD biomarkers predicted the onset of driving difficulties among OAs. METHODS: 104 OAs (65+ years) with normal cognition took part in biomarker measurements, a road test, clinical and psychometric batteries and self-reported their driving habits. RESULTS: Higher values of CSF tau/Aß42 and ptau181/Aß42 ratios, but not uptake on PIB amyloid imaging (p=.12), predicted time to a rating of Marginal or Fail on the driving test using Cox proportional hazards models. Hazards ratios (95% confidence interval) were 5.75 (1.70-19.53), p=.005 for CSF tau/Aß42; 6.19 (1.75-21.88) and p=.005 for CSF ptau181/Aß42. DISCUSSION: Preclinical AD predicted time to receiving a Marginal or Fail rating on an on-road driving test. Driving performance shows promise as a functional outcome in AD prevention trials.

Amyloid Imaging, Cerebrospinal Fluid Biomarkers Predict Driving Performance Among Cognitively Normal Individuals.

Postmortem brain studies of older drivers killed in car accidents indicate that many had Alzheimer disease (AD) neuropathologic changes. We examined whether AD biomarkers are related to driving performance among cognitively normal older adults. Individuals with normal cognition, aged 65+ years, and driving at least once per week, were recruited. Participants (N=129) took part in clinical assessments, a driving test, and positron emission tomography imaging with Pittsburgh compound B (PIB) and/or cerebrospinal fluid (CSF) collection. General linear models tested whether the number of driving errors differed as a function of each of the biomarker variables (mean cortical binding potential for PIB, and CSF Aß42, tau, ptau181, tau/Aß42, ptau181/Aß42). Higher ratios of CSF tau/Aß42, ptau181/Aß42, and PIB mean cortical binding potential, were associated with more driving errors (P<0.05). Preclinical AD may have subtle cognitive and functional effects, which alone may go unnoticed. However, when combined, these changes may impact complex behaviors such as driving.

Association of Functional Impairments and Co-Morbid Conditions with Driving Performance among Cognitively Normal Older Adults.

OBJECTIVES: To examine the relationship between key functional impairments, co-morbid conditions and driving performance in a sample of cognitively normal older adults. DESIGN: Prospective observational study. SETTING: The Knight Alzheimer's Disease Research Center, Washington University at St. Louis. PARTICIPANTS: Individuals with normal cognition, 64.9 to 88.2 years old (N = 129), with a valid driver's license, who were currently driving at least once per week, and who had participated in longitudinal studies at the Knight Alzheimer's Disease Research Center. MEASUREMENTS: Static visual acuity, contrast sensitivity, physical frailty measures, motor skills, total medical conditions, and the modified Washington University Road Test. RESULTS: When controlling for age, race, gender, APOE, and education the total number of medical conditions was unassociated with both road test scores (pass vs. marginal + fail) and the total driver error count. There were marginal associations of our measure of physical frailty (p = 0.06) and contrast sensitivity score (p = 0.06) with total driving error count. CONCLUSION: Future research that focuses on older adults and driving should consider adopting measures of physical frailty and contrast sensitivity, especially in samples that may have a propensity for disease impacting visual and/or physical function (e.g. osteoarthritis, Parkinson's, eye disorders, advanced age >80 years, etc.).

Clinical Utility of the Trail-Making Test as a Predictor of Driving Performance in Older Adults.

OBJECTIVES: To assess the clinical utility of the Trail-Making Tests (TMTs) as screens for impaired road-test performance. DESIGN: Secondary analyses of three data sets from previously published studies of impaired driving in older adults using comparable road test designs and outcome measures. SETTING: Two academic driving specialty clinics. PARTICIPANTS: Older drivers (N = 392; 303 with cognitive impairment, 89 controls) from Rhode Island and Missouri. MEASUREMENTS: Standard operating characteristics were evaluated for the TMT Part A (TMT-A) and Part B (TMT-B), as well as optimal upper and lower test cut-points that could be useful in defining groups of drivers with indeterminate likelihood of impaired driving who would most benefit from further screening or on-road testing. RESULTS: Discrimination remained high (>70%) when cut-points for the TMTs derived from Rhode Island data were applied to Missouri data, but calibration was poor (all P < .01). TMT-A provided the best utility for determining a range of scores (68-90 seconds) for which additional road testing would be indicated in general practice settings. A high frequency of cognitively impaired participants unable to perform the TMT-B test within the allotted time limited the utility of the test (>25%). Mere inability to complete the test in a reasonable time frame (e.g., TMT-A > 48 seconds or TMT-B > 108 seconds) may still be a useful tool in separating unsafe from safe or marginal drivers in such samples. CONCLUSION: The TMTs (particularly TMT-A) may be useful as screens for driving impairment in older drivers in general practice settings, where most people are still safe drivers, but more-precise screening measures need to be analyzed critically in a variety of clinical settings for testing cognitively impaired older drivers.

Driving Errors in Persons with Dementia.

OBJECTIVES: To differentiate driving errors in persons with dementia who fail a performance- based road test from errors in persons who pass. DESIGN: Cross-sectional. SETTING: Community. PARTICIPANTS: Active drivers diagnosed with dementia (n = 60) and older adult controls (n = 32). MEASUREMENT: All participants completed a standardized clinical and on-road driving assessment. The outcome variable was the number and types of driving errors according to the Record of Driving Errors (RODE), a standardized tool to record driving errors. RESULTS: Sixty-two percent (n = 37) of individuals with dementia and 3% (n = 1) of controls failed the road test. Based on the RODE, individuals with dementia made twice as many driving errors as healthy controls. Within the dementia sample, individuals who failed the road test had more difficulties driving straight and making left and right turns than during lane changes. Dangerous actions occurred most often while driving straight and making left turns. Specific driving behaviors associated with road test failure in the sample with dementia included difficulties in lane positioning and usage, stopping the vehicle appropriately, attention, decision-making, and following rules of the road. Informants of participants with dementia who failed the road test reported more impairment with cognitive functioning on the Assessing Dementia 8 Screening Interview (AD8). CONCLUSION: This report highlights the driving errors most common in people with dementia who fail a road test. The finding that most of the dangerous actions in the sample with dementia occurred while driving straight condition is novel. Driving on straight roads has not been considered a condition of "high challenge" in prior driving studies in individuals with dementia. This finding has potential implications for future interventions related to vehicle instrumentation and driving recommendations for people with dementia.

Interrater Reliability of the Record of Driving Errors (RODE).

The Record of Driving Errors (RODE) is a novel standardized tool designed to quantitatively document the specific types of driving errors that occur during a standardized performance-based road test. The purpose of this study was to determine interrater reliability between two occupational therapy driver rehabilitation specialists who quantitatively scored specific driving errors using the RODE in a sample of older adults diagnosed with dementia (n=24). Intraclass correlation coefficients of major driving error and intervention categories indicated almost perfect agreement between raters. Using raters with adequate training and similar professional backgrounds, it is possible to have good interrater reliability using the RODE on a standardized road test.

Predicting road test performance in drivers with stroke.

OBJECTIVE. The aim of this study was to develop a brief screening battery to predict the on-road performance of drivers who had experienced a stroke. METHOD. We examined 72 people with stroke referred by community physicians to an academic rehabilitation center. The outcome variable was pass or fail on the modified Washington University Road Test. Predictor measures were tests of visual, motor, and cognitive functioning. RESULTS. The best predictive model for failure on the road test included Trail Making Test Part A and the Snellgrove Maze Task(®). CONCLUSION. A screening battery that can be performed in less than 5 min was able to assist in the prediction of road test performance in a sample of drivers with stroke. A probability of failure calculator may be useful for clinicians in their decision to refer clients with stroke for a comprehensive driving evaluation.

Potentially driver-impairing (PDI) medication use in medically impaired adults referred for driving evaluation.

BACKGROUND: Potentially driver-impairing (PDI) medications have been associated with poorer driving performance and increased risk of motor vehicle collision. OBJECTIVES: To describe the frequency of medication use and to determine the association between routine use of PDI medications and performance on driving and cognitive tests. METHODS: A total of 225 drivers with medical impairment (mean age 68 ± 12.8 years, 62.2% male) were referred to an occupational therapy-based driving evaluation clinic. Medication lists were reviewed to identify PDI drugs, as defined by a previous study examining medications and crash risk. Outcome variables included road testing on the modified Washington University Road Test and cognitive scores on Trail Making Test Parts A and B, Snellgrove Maze Task, Clock Drawing Task, Driving Health Inventory (DHI) Useful Field of View, DHI Motor Free Visual Perceptual Test, Epworth Sleepiness Scale (ESS), Geriatric Depression Scale, and Functional Assessment Questionnaire. RESULTS: PDI medication use was documented in 68.9% of the sample, with the average subject taking 1.4 PDI drugs. Drivers taking routine PDI medications had a mean ESS score of 7.8 compared to 6.0 in the control group, suggesting increased somnolence (P = .007). Total number of routine medications, regardless of PDI designation, also correlated positively with ESS scores (P = .023). CONCLUSIONS: Use of PDI medications was associated with informant ratings of daytime drowsiness on the ESS, which has been linked to motor vehicle crash risk. Further investigation of individual drug classes is warranted using larger sample sizes and a high-powered study design.

Predictors of return to driving after stroke.

OBJECTIVE: Although returning to driving is a major concern for many survivors of stroke, predicting who will return to driving after a stroke is often difficult for rehabilitation professionals. The primary aim of this study was to identify patient factors present at admission to an inpatient rehabilitation hospital that can be used to identify which patients who have had acute stroke will and will not return to driving. DESIGN: After comparing returners and nonreturners on demographic and clinical characteristics, a logistic regression model with return to driving as the outcome variable was built using the backward stepwise method. RESULTS: Thirty-one percent (48/156) of the patients who had been driving before their stroke returned to driving 6 mos after stroke. The final regression model, using Functional Independence Measure cognition and lower extremity Motricity Index scores, predicted the driving outcome with an accuracy of 75% (107/143). CONCLUSIONS: Patients with lower Functional Independence Measure cognition and lower extremity Motricity Index scores at admission to inpatient rehabilitation are less likely to return to driving at 6 mos. This model could be used by rehabilitation professionals to help counsel patients and their families and focus treatment goals.

Naturalistic validation of an on-road driving test of older drivers.

OBJECTIVE: The objective was to compare a standardized road test to naturalistic driving by older people who may have cognitive impairment to define improvements that could potentially enhance the validity of road testing in this population. BACKGROUND: Road testing has been widely adapted as a tool to assess driving competence of older people who may be at risk for unsafe driving because of dementia; however, the validity of this approach has not been rigorously evaluated. METHOD: For 2 weeks, 80 older drivers (38 healthy elders and 42 with cognitive impairment) who passed a standardized road test were video recorded in their own vehicles. Using a standardized rating scale, 4 hr of video was rated by a driving instructor. The authors examine weighting of individual road test items to form global impressions and to compare road test and naturalistic driving using factor analyses of these two assessments. RESULTS: The road test score was unidimensional, reflecting a major factor related to awareness of signage and traffic behavior. Naturalistic driving reflected two factors related to lane keeping as well as traffic behavior. CONCLUSION: Maintenance of proper lane is an important dimension of driving safety that appears to be relatively underemphasized during the highly supervised procedures of the standardized road test. APPLICATION: Road testing in this population could be improved by standardized designs that emphasize lane keeping and that include self-directed driving. Additional information should be sought from observers in the community as well as crash evidence when advising older drivers who may be cognitively impaired.

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

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

Predicting road test performance in drivers with dementia.

OBJECTIVES: To develop a cognitive and functional screening battery for the on-road performance of older drivers with dementia. DESIGN: Prospective observational study. SETTING: On-road driving evaluation clinic at an academic rehabilitation center. PARTICIPANTS: Ninety-nine older people with dementia (63% male, mean age 74.2 ± 9), referred by community physicians to an occupational therapy driving clinic. MEASUREMENTS: The outcome variable was pass or fail on the modified Washington University Road Test. Predictor measures were tests of visual, motor, and cognitive functioning, selected for their empirical or conceptual relationship to the complex task of driving safely. RESULTS: Sixty-five (65%) participants failed the on-road driving test. The best predictive model, with an overall accuracy of up to 85% when participants were blinded, included the Eight-item Informant Interview to Differentiate Aging and Dementia, Clock Drawing Test score, and time to complete the Snellgrove Maze Test or Trail Making Test Part A. Visual and motor functioning were not associated with road test failure. CONCLUSION: A screening battery that could be performed in less than 10 minutes predicted with good accuracy failure rate for the on-road driving test in this sample of older drivers with dementia. A probability of failure calculator is provided from a logistic regression model that may be useful for clinicians in their decision to refer impaired older adults for further testing. More studies are needed in larger community-based samples, along with discussions with patients, families, and clinicians, with regard to acceptable levels of test uncertainty.