Driving performance in persons with mild senile dementia of the Alzheimer type

Effect of Behavioral Precaution on Braking Operation of Elderly Drivers under Cognitive Workloads

The number of accidents by elderly drivers caused by the erroneous tread of a brake pedal or accelerator pedal has increased. A recent study reported that the number of accidents could be reduced by preparing for braking mistakes due to driving behavior by using a simulator. However, related studies have pointed out that driving behavior in simulators does not always reflect driving behavior in the real world. This paper focuses on the posture of the left foot as a behavioral precaution and provides insights into braking mistakes by comparing behavioral precautions taken on simulators and on public roads. In the experimental results, cognitive and action errors increased with age, but elderly drivers are less likely to have an accident when they are exposed to the risk of collision in situations with a mental workload by making space for the right foot to step on the brake pedal. Elderly drivers with coping skills had their left foot perpendicular to the ground and their body was unstable. This result was different from the driving behavior in the simulator, but it was not possible to identify that this difference was the cause of the collision accidents. Coping skills were predicted with 70% accuracy from the left foot posture of an elderly driver near the intersection. We expanded the system's range of use and enhanced its usefulness by predicting coping skills derived from natural driving behavior in the real world. The contributions of this study are as follows. We clarify the effect of behavioral precautions on the braking operation of elderly drivers when under a cognitive workload. We provide new insights into the use of behavioral precautions in older drivers' braking operations in the real world. We predicted coping skills from natural driving behavior near intersections in the real world.

Medicolegal Implications of Mild Neurocognitive Disorder

INTRODUCTION

The syndromes of mild cognitive impairment (MCI) or mild neurocognitive disorder (MiND), often prodromal to dementia (Major Neurocognitive Disorder), are characterized by acquired clinically significant changes in one or more cognitive domains despite preserved independence. Mild impairment has significant medicolegal consequences for an affected person and their care system. We review the more common etiologies of MiND and provide a systematic review of its medicolegal implications.

METHODS

We conducted a systematic review of the peer-reviewed English literature on medicolegal aspects of MCI or MiND using comprehensive search terms and expanding our review to include sources cited by these reports.

RESULTS

Impairment of memory, executive function, social cognition, judgment, insight or abstraction can alter an individual's abilities in a variety of areas that include decision making, informed consent, designation of a surrogate decision-maker such as a health care proxy, understanding and management of financial affairs, execution of a will, or safe driving.

CONCLUSION

Even mild cognitive impairment can have significant behavioral consequences. Clinicians can assist care partners and persons with MCI or MiND by alerting them to the medicolegal concerns that often accompany cognitive decline. Early recognition and discussion can help a care system manage medicolegal risk more effectively and promote thoughtful advance planning.

Driving and Alzheimer's dementia or mild cognitive impairment: a systematic review of the existing guidelines emphasizing on the neurologist's role

BACKGROUND

Driving is a complex task requiring the integrity and the cooperation of cognition, motor, and somatosensory skills, all of which are impacted by neurological diseases.

OBJECTIVE

Identification of neurologist's role when assessing fitness to drive of cognitively impaired individuals.

METHODS

We performed a systematic review of the guidelines/recommendations (G/Rs) regarding the evaluation of driving fitness of patients with mild cognitive impairment (MCI) and/or dementia. Emphasis was put on the neurological and neuropsychological aspects of the evaluation.

RESULTS

Eighteen G/Rs were included in the review (9 national guidelines, 5 recommendation papers, 3 consensus statements, and 1 position paper). All G/Rs referred to drivers with dementia and 9/18 referred to drivers with MCI. A common approach among G/Rs is the initial trichotomization of patients in safe to drive, unsafe to drive, and undetermined cases, which are referred to a second-line evaluator. First-line evaluators are general practitioners in 10/18 G/Rs; second-line evaluators are neurologists in 7/18 G/Rs. Specific neuropsychological tests are proposed in 11/18 G/Rs and relative cut-off values in 7/18. The most commonly used tests are the MMSE, TMT, and CDT. A thorough neurological examination is proposed in only 1/18 G/R.

CONCLUSION

Although extensive multi-disciplinary research has provided useful information for driving behavior of cognitively impaired individuals, we are still far from a widely accepted approach of driving ability evaluation in this increasing population. A comprehensive assessment from a multi-disciplinary team in which the neurologist plays a critical role seems to be required, although this has not yet been implemented in any G/Rs.

Off-road assessment of cognitive fitness to drive

Road safety is a major issue in every society. The assessment of driving ability with a real vehicle is a lengthy and costly process; therefore, there is a growing need for the development of a neuropsychological battery that can provide a fast and reliable evaluation of a person's cognitive fitness to drive. In the present study, we examined the relationship of an off-road lab-type test, namely, the Driving Scenes test, with performance on a driving simulator, as well as the influence of cognitive factors on driving ability as evaluated by Driving Scenes. Our results demonstrated a relationship between Driving Scenes and driving simulator performance. They also showed that some cognitive factors (namely, selective attention and verbal memory), were predictive of driving ability (as determined by the Driving Scenes test), but not others (namely visuospatial perception/memory, working memory, and visuospatial recognition). In addition, age strongly predicted performance on this test (younger age was associated with better performance). The conclusions derived from the present study highlight the need to identify off-road tools with high predictive value in assessing driving ability.

Altered awareness of motor symptoms in Parkinson's disease and Dementia with Lewy Bodies: A systematic review

OBJECTIVES

Altered awareness of motor symptoms is reported in people with Parkinson's disease and Dementia with Lewy Bodies, and may adversely affect quality of life and medication concordance. How symptom awareness is influenced by motor and cognitive disease severity, age and medication use is not fully understood. We carried out a systematic review of the literature on motor symptom awareness in Parkinson's disease and Dementia with Lewy Bodies.

METHODS

Pubmed and Wed of Science were searched for relevant articles published in or prior to March 2019. Data regarding participant demographics, diagnosis, cognitive status, method of assessing awareness and study findings were extracted from relevant publications.

RESULTS

Sixteen relevant publications were identified. Motor symptom awareness appears to decline over the course of Parkinson's disease. Imaging studies implicate the prefrontal cortex, with different mechanisms involved in hypokinesia and dyskinesia awareness. The hypothesis that people with right hemisphere based disease would have more severely reduced awareness is only weakly supported. Most studies focused on cognitively intact individuals, and on awareness of dyskinesia rather than hypokinesia.

CONCLUSIONS

Whilst reduced awareness of dyskinesia and to a lesser extent hypokinesia is common, there is a lack of longitudinal data on how awareness changes over time, and how it interacts with global cognitive changes. Motor symptom awareness in Dementia with Lewy Bodies is understudied. Future studies of symptom awareness should include robust assessment of overall cognitive functioning, and use a longitudinal design to elucidate how awareness changes over time. J Am Geriatr Soc 68:-, 2020.

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

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

Personal and Clinical Factors Associated with Older Drivers' Self-Awareness of Driving Performance

Most older adults perceive themselves as good drivers; however, their perception may not be accurate, and could negatively affect their driving safety. This study examined the accuracy of older drivers' self-awareness of driving ability in their everyday driving environment by determining the concordance between the perceived (assessed by the Perceived Driving Ability [PDA] questionnaire) and actual (assessed by electronic Driving Observation Schedule [eDOS]) driving performance. One hundred and eight older drivers (male: 67.6%; age: mean = 80.6 years, standard deviation [SD] = 4.9 years) who participated in the study were classified into three groups: underestimation (19%), accurate estimation (29%), and overestimation (53%). Using the demographic and clinical functioning information collected in the Candrive annual assessments, an ordinal regression showed that two factors were related to the accuracy of self-awareness: older drivers with better visuo-motor processing speed measured by the Trail Making Test (TMT)-A and fewer self-reported comorbid conditions tended to overestimate their driving ability, and vice versa.

Adherence to driving cessation advice given to patients with cognitive impairment and consequences for mobility

BACKGROUND

Driving is related to social participation; therefore older drivers may be reluctant to cease driving. Continuation of driving has also been reported in a large proportion of patients with cognitive impairment. The aim of this study is to investigate whether patients with cognitive impairment adhere to driving cessation advice after a fitness-to-drive assessment and what the consequences are with regard to mobility.

METHODS

Patients with cognitive impairment (n = 172) participated in a fitness-to-drive assessment study, including an on-road driving assessment. Afterwards, patients were advised to either continue driving, to follow driving lessons, or to cease driving. Approximately seven months thereafter, patients were asked in a follow-up interview about their adherence to the driving recommendation. Factors influencing driving cessation were identified using a binary logistic regression analysis. Use of alternative transportation was also evaluated.

RESULTS

Respectively 92 and 79% of the patients adhered to the recommendation to continue or cease driving. Female gender, a higher Clinical Dementia Rating-score, perceived health decline, and driving cessation advice facilitated driving cessation. Patients who ceased driving made use of less alternative modes of transportation than patients who still drove. Nonetheless, around 40% of the patients who ceased driving increased their frequency of cycling and/or public transport use.

CONCLUSIONS

Adherence to the recommendations given after the fitness-to-drive assessments was high. Female patients were in general more likely to cease driving. However, a minority of patients did not adhere to driving cessation advice. These drivers with dementia should be made aware of the progression of their cognitive impairment and general health decline to facilitate driving cessation. There are large differences in mobility between patients with cognitive impairment. Physicians should discuss options for alternative transportation in order to promote sustained safe mobility of patients with cognitive impairment.

Computer-Based Driving in Dementia Decision Tool With Mail Support: Cluster Randomized Controlled Trial

Background

Physicians often find significant challenges in assessing automobile driving in persons with mild cognitive impairment and mild dementia and deciding when to report to transportation administrators. Care must be taken to balance the safety of patients and other road users with potential negative effects of issuing such reports.

Objective

The aim of this study was to assess whether a computer-based Driving in Dementia Decision Tool (DD-DT) increased appropriate reporting of patients with mild dementia or mild cognitive impairment to transportation administrators.

Methods

The study used a parallel-group cluster nonblinded randomized controlled trial design to test a multifaceted knowledge translation intervention. The intervention included a computer-based decision support system activated by the physician-user, which provides a recommendation about whether to report patients with mild dementia or mild cognitive impairment to transportation administrators, based on an algorithm derived from earlier work. The intervention also included a mailed educational package and Web-based specialized reporting forms. Specialists and family physicians with expertise in dementia or care of the elderly were stratified by sex and randomized to either use the DD-DT or a control version of the tool that required identical data input as the intervention group, but instead generated a generic reminder about the reporting legislation in Ontario, Canada. The trial ran from September 9, 2014 to January 29, 2016, and the primary outcome was the number of reports made to the transportation administrators concordant with the algorithm.

Results

A total of 69 participating physicians were randomized, and 36 of these used the DD-DT; 20 of the 35 randomized to the intervention group used DD-DT with 114 patients, and 16 of the 34 randomized to the control group used it with 103 patients. The proportion of all assessed patients reported to the transportation administrators concordant with recommendation did not differ between the intervention and the control groups (50% vs 49%; Z=−0.19, P=.85). Two variables predicted algorithm-based reporting—caregiver concern (odds ratio [OR]=5.8, 95% CI 2.5-13.6, P<.001) and abnormal clock drawing (OR 6.1, 95% CI 3.1-11.8, P<.001).

Conclusions

On the basis of this quantitative analysis, in-office abnormal clock drawing and expressions of concern about driving from caregivers substantially influenced physicians to report patients with mild dementia or mild cognitive impairment to transportation administrators, but the DD-DT tool itself did not increase such reports among these expert physicians.

Trial Registration

ClinicalTrials.gov NCT02036099; https://clinicaltrials.gov/ct2/show/NCT02036099 (Archived by WebCite at http://www.webcitation.org/6zGMF1ky8)

Mood and Personality Characteristics are Associated with Metamemory Knowledge Accuracy in a Community-Based Cohort of Older Adults

OBJECTIVES

Emerging work reveals the neuroanatomic changes that compromise metacognition; however, little is known about the impact of premorbid factors. Research suggests that psychological variables influence the perception of cognition, but whether they influence the accuracy of those perceptions (i.e., metacognition) has not been directly examined.

PARTICIPANTS AND METHODS

Using Latent Class Analysis (LCA), we tested for discrete personality (NEOFFI) and mood (STAI, BDI-II, and GDS) classes among a community-based cohort of 151 older adults, enrolled in the NKI-Rockland study. Metamemory was calculated by comparing subjective memory ratings (modified Cognitive Failures Questionnaire) to objective memory (Rey Auditory Verbal Learning Test) to determine the degree to which individuals were overconfident, underconfident, or accurate in their self-assessment. A generalized linear model was used to examine whether metamemory differed across the emergent classes. A one sample t test was used to determine whether the metamemory scores of the emergent classes were statistically significantly different from zero, that is, over or under confident.

RESULTS

Two discrete classes emerged in the LCA: Class 1 was characterized predominantly by high extraversion and conscientiousness and low neuroticism and anxiety; Class 2 was characterized predominantly by low extraversion and conscientiousness and high neuroticism and anxiety. Metamemory differed significantly as a function of Class Membership (F(4,151)=5.42; p<.001), with Class 1 demonstrating accurate metamemory (M=0.21; SD=1.31) and Class 2 demonstrating under-confidence (M=-0.59; SD=1.39) in their memory.

CONCLUSIONS

The significant association between psychological factors and metamemory knowledge accuracy suggests that such characteristics may be important to consider in the conceptualization, assessment, and treatment of metacognitive disturbances. (JINS, 2018, 24, 498-510).

General cognitive impairment as a risk factor for motor vehicle collision involvement: a prospective population-based study

This study examined whether cognitive impairment and decline as assessed by a brief mental status screening test is associated with future crash risk in a cohort of older drivers. A three-year prospective study was conducted in a population-based sample of 2000 licensed drivers, aged 70 years and older. At the baseline visit, cognitive impairment was defined as <24 on the Mini Mental State Exam (MMSE). Decline was defined as those with a one-year change in MMSE scores in the lowest quartile (largest decrease). Motor vehicle collision involvement was obtained from the Alabama Department of Public Safety. Poisson regression was used to calculate crude and adjusted rate ratios (RR). There were 278 crashes during the follow-up period. Rates of crash involvement were higher for those with cognitive impairment (crude RR = 2.33) compared to those without impairment at baseline; adjustment for potential confounders namely age and visual processing speed attenuated this relationship (adjusted RR = 1.26, 95% confidence interval (CI) 0.65–2.44). Drivers who experienced a pronounced decline in estimated MMSE scores in one year were 1.64 (95% CI 1.04–2.57) times more likely to have a future at-fault crash, as compared to those whose scores did not decline. Evaluation of MMSE over time may provide important insight in an older driver’s future risk of at-fault crash involvement.

Relationship between areas of cognitive functioning on the Mini-Mental State Examination and crash risk

Previous studies have suggested that the pattern of cognitive impairment in crash-involved older drivers is different from non-crash-involved older drivers. This study assessed the relationship between seven areas of cognitive functioning (orientation to time, orientation to place, registration, attention and calculation, recall, language, and visual construction) on the Mini-Mental State Examination (MMSE) collected at baseline and rates of future crash involvement in a prospective population-based sample of older drivers. Motor vehicle collision (MVC) involvement was obtained from the Alabama Department of Public Safety. Poisson regression was used to calculate crude and adjusted rate ratios (RR). Older drivers having difficulties in place orientation were more than 6 times (95% CI 1.90–19.86) more likely to be involved in a future crash (adjusted RR = 6.14, 95% confidence interval (CI) 1.90–19.86) and at-fault crash (adjusted RR = 6.39, 95% CI 1.51–27.10). Impairment in the other cognitive areas was not associated with higher rates of crash or at-fault crash involvement. The findings were validated in an independent sample of high-risk older drivers and a similar pattern of results was observed. Spatial orientation impairment can help identify older drivers who are more likely to crash in the future.

Psychometrics of the AAN Caregiver Driving Safety Questionnaire and contributors to caregiver concern about driving safety in older adults

ABSTRACTBackground:The American Academy of Neurology (AAN) updated their practice parameters in the evaluation of driving risk in dementia and developed a Caregiver Driving Safety Questionnaire, detailed in their original manuscript (Iverson Gronseth, Reger, Classen, Dubinsky, & Rizzo, 2010). They described four factors associated with decreased driving ability in dementia patients: history of crashes or citations, informant-reported concerns, reduced mileage, and aggressive driving.

METHOD

An informant-reported AAN Caregiver Driving Safety Questionnaire was designed with these elements, and the current study was the first to explore the factor structure of this questionnaire. Additionally, we examined associations between these factors and cognitive and behavioral measures in patients with mild cognitive impairment or early Alzheimer's disease and their informants.

RESULTS

Exploratory factor analysis revealed a four-component structure, consistent with the theory behind the AAN scale composition. These four factor scores also were significantly associated with performance on cognitive screening instruments and informant reported behavioral dysfunction. Regressions revealed that behavioral dysfunction predicted caregiver concerns about driving safety beyond objective patient cognitive dysfunction.

CONCLUSIONS

In this first known quantitative exploration of the scale, our results support continued use of this scale in office driving safety assessments. Additionally, patient behavioral changes predicted caregiver concerns about driving safety over and above cognitive status, which suggests that caregivers may benefit from psychoeducation about cognitive factors that may negatively impact driving safety.

A Systematic Review and Meta-Analysis of On-Road Simulator and Cognitive Driving Assessment in Alzheimer's Disease and Mild Cognitive Impairment

BACKGROUND

Many individuals with Alzheimer's disease (AD) and mild cognitive impairment (MCI) are at an increased risk of driving impairment. There is a need for tools with sufficient validity to help clinicians assess driving ability.

OBJECTIVE

Provide a systematic review and meta-analysis of the primary driving assessment methods (on-road, cognitive, driving simulation assessments) in patients with MCI and AD.

METHODS

We investigated (1) the predictive utility of cognitive tests and domains, and (2) the areas and degree of driving impairment in patients with MCI and AD. Effect sizes were derived and analyzed in a random effects model.

RESULTS

Thirty-two articles (including 1,293 AD patients, 92 MCI patients, 2,040 healthy older controls) met inclusion criteria. Driving outcomes included: On-road test scores, pass/fail classifications, errors; caregiver reports; real world crash involvement; and driving simulator collisions/risky behavior. Executive function (ES [95% CI]; 0.61 [0.41, 0.81]), attention (0.55 [0.33, 0.77]), visuospatial function (0.50 [0.34, 0.65]), and global cognition (0.61 [0.39, 0.83]) emerged as significant predictors of driving performance. Trail Making Test Part B (TMT-B, 0.61 [0.28, 0.94]), TMT-A (0.65 [0.08, 1.21]), and Maze test (0.88 [0.60, 1.15]) emerged as the best single predictors of driving performance. Patients with very mild AD (CDR = 0.5) mild AD (CDR = 1) were more likely to fail an on-road test than healthy control drivers (CDR = 0), with failure rates of 13.6%, 33.3% and 1.6%, respectively.

CONCLUSION

The driving ability of patients with MCI and AD appears to be related to degree of cognitive impairment. Across studies, there are inconsistent cognitive predictors and reported driving outcomes in MCI and AD patients. Future large-scale studies should investigate the driving performance and associated neural networks of subgroups of AD (very mild, mild, moderate) and MCI (amnestic, non-amnestic, single-domain, multiple-domain).

Highly Cited Occupational Therapy Articles in the Science Citation Index Expanded and Social Sciences Citation Index: A Bibliometric Analysis

OBJECTIVE

A bibliometric analysis was completed of highly cited occupational therapy literature and authors published from 1991 to 2014 and accessible in the Science Citation Index Expanded (SCI-Expanded) and Social Sciences Citation Index (SSCI) databases.

METHOD

Data were obtained from the SCI-Expanded and SSCI. Articles referenced >100 times were categorized as highly cited articles (HCA).

RESULTS

Of 6,486 articles found, 31 were categorized as HCA. The American Journal of Occupational Therapy published the largest number of HCA (n = 8; 26%). The 31 HCA were distributed across seven countries: United States (20 articles), Canada (3), United Kingdom (3), Australia (2), the Netherlands (1), New Zealand (1), and Sweden (1). The three authors with the highest Y-index were S. J. Page, F. Clark, and W. Dunn.

CONCLUSION

A latency period of 4 to 5 yr post-publication appears to be needed for a journal article to gain citations.

Development of a decision-making tool for reporting drivers with mild dementia and mild cognitive impairment to transportation administrators

BACKGROUND

Driving in persons with dementia poses risks that must be counterbalanced with the importance of the care for autonomy and mobility. Physicians often find substantial challenges in the assessment and reporting of driving safety for persons with dementia. This paper describes a driving in dementia decision tool (DD-DT) developed to aid physicians in deciding when to report older drivers with either mild dementia or mild cognitive impairment to local transportation administrators.

METHODS

A multi-faceted, computerized decision support tool was developed, using a systematic literature and guideline review, expert opinion from an earlier Delphi study, as well as qualitative interviews and focus groups with physicians, caregivers of former drivers with dementia, and transportation administrators. The tool integrates inputs from the physician-user about the patient's clinical and driving history as well as cognitive findings, and it produces a recommendation for reporting to transportation administrators. This recommendation is translated into a customized reporting form for the transportation authority, if applicable, and additional resources are provided for the patient and caregiver.

CONCLUSIONS

An innovative approach was needed to develop the DD-DT. The literature and guideline review confirmed the algorithm derived from the earlier Delphi study, and barriers identified in the qualitative research were incorporated into the design of the tool.

A Bibliometric Analysis of Highly Cited and High Impact Occupational Therapy Publications by American Authors

A bibliometric analysis was completed of peer-reviewed literature from 1991-2015, written by American occupational therapists, to examine US high impact scholarship with "occupational therapy" and "occupational therapist(s)" used as keywords to search journal articles' publication title, abstract, author details, and keywords. Results included 1,889 journal articles from 1991-2015 published by American occupational therapists as first or corresponding author. Sixty-nine articles attained a TotalCitation₂₀₁₅ ≥ 50 and 151 attained a Citation₂₀₁₅ ≥ 5 indicating that they were the most highly cited literature produced in this period. Although the majority (58%) of this literature was published in occupational therapy-specific journals, 41% was published in interdisciplinary journals. Results illustrate that the volume of highly cited American occupational therapy peer-reviewed literature has grown over the last two decades. There is need for the profession to strategize methods to enhance the publication metrics of occupational therapy-specific journals to reduce the loss of high quality publications to external periodicals.

Older Adults with Mild Cognitive Impairments Show Less Driving Errors after a Multiple Sessions Simulator Training Program but Do Not Exhibit Long Term Retention

The driving performance of individuals with mild cognitive impairment (MCI) is suboptimal when compared to healthy older adults. It is expected that the driving will worsen with the progression of the cognitive decline and thus, whether or not these individuals should continue to drive is a matter of debate. The aim of the study was to provide support to the claim that individuals with MCI can benefit from a training program and improve their overall driving performance in a driving simulator. Fifteen older drivers with MCI participated in five training sessions in a simulator (over a 21-day period) and in a 6-month recall session. During training, they received automated auditory feedback on their performance when an error was noted about various maneuvers known to be suboptimal in MCI individuals (for instance, weaving, omitting to indicate a lane change, to verify a blind spot, or to engage in a visual search before crossing an intersection). The number of errors was compiled for eight different maneuvers for all sessions. For the initial five sessions, a gradual and significant decrease in the number of errors was observed, indicating learning and safer driving. The level of performance, however, was not maintained at the 6-month recall session. Nevertheless, the initial learning observed opens up possibilities to undertake more regular interventions to maintain driving skills and safe driving in MCI individuals.

A simulated driving evaluation for patients with Alzheimer's disease

A prospective study concerning the driving ability of 41 patients with the diagnosis of Alzheimer's disease (AD) was performed. Using a simulated driving test we evaluated the predictive value of the MMSE,'4ADL,5-7and IADL&9to determine the ability of a person with Alzheimer's disease to drive. All patients were driving at the time of the evaluation.

There was no correlation between driving performance and functional status evaluated by ADL and IADL. When comparing driving performance with cognitive evaluation by MMSE, a significant number of patients with MMSE c 22failed the test, compared to patients with MMSE > 22 (P = 0.01, Fisher's exact test).

No patient with a MMSE < 20 passed the driving test. The authors recommend that health care professionals who are caring for people with Alzheimer's disease with a MMSE of22 or less should request a driving evaluation.

The “Co-pilot driveer syndrome:” A newly-reported driving habit in patients with Alzheimer's diseas

When should I take away the car keys? Is it still safe for him/her to drive? Are all patients diagnosed with Alzheimer's disease (AD) a hazard on the road? What about driving for short distances in a familiar territory? Can people with AD drive with family or caregiver supervision? Those are but a few of the difficult questions asked by caregivers of people with AD. There is confusion regarding the optimal time to recommend that a patient with AD stop driving.1-5 In an attempt to assist caregivers with this difficult question, guidelines have been issued, although they frequently have conflicting recommendations in this matter.6-10

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

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

Awareness Deficits in Alzheimer's Disease: Issues in Assessment and Intervention

Unawareness of deficits is a challenging problem frequently encountered in individuals with Alzheimer's disease (AD). Understanding mediating and causative factors of unawareness is important for accurate assessment and effective intervention. However, clinicians should also consider the variability that is often present between and within AD patients and should avoid the use of dichotomous classifications of unawareness. In this article, current knowledge generated by both neurosciences and behavioral sciences provides the basis for identifying issues and offering recommendations pertinent to assessment and intervention of awareness deficits m AD. Remedial and compensatory efforts used with head-injured patients may have potential application to dementia patients with awareness deficits, especially for those in earlier stages. Knowledge in this area is still in an early stage of investigation. As more is known about the nature of awareness deficits, it will be possible to design more effective approaches based on the characteristics of individual patients.

The Functional Spatial Abilities Questionnaire for Use with Persons Who are in the Early Stages of Alzheimer Disease: Preliminary Data on Reliability and Validity

The 12-item Functional Spatial Abilities Questionnaire (FSAQ) was developed for evaluating spatial orientation in clients who have progressive dementia of the Alzheimer type. Twenty-five clients in the early stages of Alzheimer disease, ten clients in the later stage of the disease and 97 normal subjects rated themselves on the questionnaire. A proxy version of the questionnaire was administered to a caregiver or relative of each subject in the three groups. The FSAQ demonstrated acceptable test-retest reliability (ICCs = .84 to .85). Construct validity was examined in three ways. First, using the known group method, the proxy-ratings were shown to discriminate between early and late Alzheimer clients, but not the self-ratings. Second, there was a high agreement between the self-and proxy-ratings in the early Alzheimer group indicating concurrent validity. Third, the FSAQ scores did not correlate with mental status examination scores which provides evidence for discriminant validity. The FSAQ is quick to administer and provides occupational therapists with a basis for further evaluation of a client's ability to find his or her way in new or familiar environments.

Prediction of Fitness to Drive in Patients with Alzheimer's Dementia

The number of patients with Alzheimer’s disease (AD) is increasing and so is the number of patients driving a car. To enable patients to retain their mobility while at the same time not endangering public safety, each patient should be assessed for fitness to drive. The aim of this study is to develop a method to assess fitness to drive in a clinical setting, using three types of assessments, i.e. clinical interviews, neuropsychological assessment and driving simulator rides. The goals are (1) to determine for each type of assessment which combination of measures is most predictive for on-road driving performance, (2) to compare the predictive value of clinical interviews, neuropsychological assessment and driving simulator evaluation and (3) to determine which combination of these assessments provides the best prediction of fitness to drive. Eighty-one patients with AD and 45 healthy individuals participated. All participated in a clinical interview, and were administered a neuropsychological test battery and a driving simulator ride (predictors). The criterion fitness to drive was determined in an on-road driving assessment by experts of the CBR Dutch driving test organisation according to their official protocol. The validity of the predictors to determine fitness to drive was explored by means of logistic regression analyses, discriminant function analyses, as well as receiver operating curve analyses. We found that all three types of assessments are predictive of on-road driving performance. Neuropsychological assessment had the highest classification accuracy followed by driving simulator rides and clinical interviews. However, combining all three types of assessments yielded the best prediction for fitness to drive in patients with AD with an overall accuracy of 92.7%, which makes this method highly valid for assessing fitness to drive in AD. This method may be used to advise patients with AD and their family members about fitness to drive.

Comparing caregiver and clinician predictions of fitness to drive in people with Alzheimer's disease

This observational study investigated family caregiver and clinician ratings of 75 drivers with Alzheimer's disease against scores on a standardized road test and a naturalistic driving evaluation. Clinician ratings by a physician specialized in dementia were significantly associated with road test error scores (r=.25, p=.03) but not naturalistic driving errors or global ratings of road test and naturalistic driving performance. Caregiver ratings were unrelated to either driving assessment, with two exceptions; adult child ratings of driving ability were correlated with road test error scores (r=.43, p=.02), and spousal ratings were inversely correlated with global ratings. Clinician ratings of driving competence were modestly correlated with road test performance, but caregiver ratings were more complex. Adult children may be more accurate reporters of driving ability than spouses, possibly because of less personal bias, but the reasons behind this discrepancy need further investigation.

Reactions to driving cessation: a qualitative study of people with dementia and their families

OBJECTIVES

A proportion of older people with mild dementia are safe to drive. However, driving cessation is recommended at some point as the disease progresses. Driving cessation can have significant psychological and social consequences on people with dementia and their carers. This paper aims to explore the psychosocial and adjustment issues following driving cessation for people with dementia and their supporters.

METHOD

Participants and their supporters were interviewed within 1 month of driving-cessation advice, and again 6 months later. Issues associated with driving cessation were explored in semi-structured interviews.

RESULTS

Seven participants and their supporters were recruited. This has generated a total of 22 transcripts for qualitative analysis including follow-up interviews. For those who could remember the details of driving cessation, most were unhappy with the decision. Carers who were supportive of driving cessation questioned the legality of it. Most participants minimised the impact of their driving cessation on their supporters. Most supporters were negatively affected by the decision.

CONCLUSIONS

The preliminary findings highlight the need for a more comprehensive process for driving cessation in those with dementia, with closer links to regulatory bodies, and increased support for their families/carers.

Performance of the Maze Navigation Test in a sample of older New Zealanders

OBJECTIVE

It is often difficult to assess the driving performance of people with mild dementia. The Maze Navigation Test (MNT) was developed in the USA and has been shown to predict driving performance. The aim of this study is to evaluate how the MNT is performed against three commonly used bedside cognitive screening tools and compare our findings with the US population.

METHODS

A convenience sample of 42 cognitively intact older people (age ≥65) completed the MNT, Mini-Mental State Examination, the revised Addenbrooke's Cognitive Examination and the Trail Making Tests.

RESULTS

The mean MNT completion time was 307.6 (SD=85.6) and 444.5 (SD=157.3) for the 65-74 years and 75-84 years age group, respectively. Pearson's product-moment correlations were strongest with the Trail Making Test Part B (r=0.602).

CONCLUSIONS

The findings of this study were comparable with the initial US data. The MNT is an easy-to-administer bedside cognitive screening tool. Further validation studies using the MNT and driving performance are warranted.

A roadmap for interpreting the literature on vision and driving

Over the past several decades there has been a sharp increase in the number of studies focused on the relationship between vision and driving. The intensified attention to this topic has most likely been stimulated by the lack of an evidence basis for determining vision standards for driving licensure and a poor understanding about how vision impairment impacts driver safety and performance. Clinicians depend on the literature on vision and driving to advise visually impaired patients appropriately about driving fitness. Policy makers also depend on the scientific literature in order to develop guidelines that are evidence-based and are thus fair to persons who are visually impaired. Thus it is important for clinicians and policy makers alike to understand how various study designs and measurement methods should be interpreted so that the conclusions and recommendations they make are not overly broad, too narrowly constrained, or even misguided. We offer a methodological framework to guide interpretations of studies on vision and driving that can also serve as a heuristic for researchers in the area. Here, we discuss research designs and general measurement methods for the study of vision as they relate to driver safety, driver performance, and driver-centered (self-reported) outcomes.

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

Introduction

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

Method

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

Results

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

Conclusion

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

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

Introduction

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

Method

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

Results

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

Conclusion

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

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

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

The impact of subclinical sleep problems on self-reported driving patterns and perceived driving abilities in a cohort of active older drivers

The present study sought to investigate the influence of subclinical sleep disturbances on driving practices and driver perceptions in a large cohort of healthy older drivers. Participants from the Candrive II prospective cohort study were investigated. Self-reported measures of sleep problems were used to determine the influence of sleep disturbance on self-reported driving practices and perceived driving abilities, as measured by the Situational Driving Frequency, Situational Driving Avoidance, and Perceived Driving Abilities scales. Hierarchical regression analyses were used to estimate whether mild self-reported sleep problems were predictive of driving restrictions and perceived abilities, while controlling for a variety of health-related factors and demographic variables known to mediate sleep problems or to impact driving. Cross-sectional analysis of baseline data from the Candrive II study suggests that subclinical sleep problems do not significantly influence self-reported driving patterns or perceived driving abilities in older drivers once control variables are considered. The relationship between sleep problems, driving frequency, avoidance and perceived abilities is better explained by mediating demographic, health, and cognitive factors. Further research examining sleep disturbances and driving should include objective measures of driving practices (exposure, patterns) and outcomes (crashes, violations) and should take in consideration the severity of sleep problems.

Driving assessment for maintaining mobility and safety in drivers with dementia

BACKGROUND

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

OBJECTIVES

PRIMARY OBJECTIVES

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

SECONDARY OBJECTIVE

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Cognitive deficits are associated with poorer simulated driving in older adults with heart failure

BACKGROUND

Cognitive impairment is prevalent in older adults with heart failure (HF) and associated with reduced functional independence. HF patients appear at risk for reduced driving ability, as past work in other medical samples has shown cognitive dysfunction to be an important contributor to driving performance. The current study examined whether cognitive dysfunction was independently associated with reduced driving simulation performance in a sample of HF patients.

METHODS

18 persons with HF (67.72; SD = 8.56 year) completed echocardiogram and a brief neuropsychological test battery assessing global cognitive function, attention/executive function, memory and motor function. All participants then completed the Kent Multidimensional Assessment Driving Simulation (K-MADS), a driving simulator scenario with good psychometric properties.

RESULTS

The sample exhibited an average Mini Mental State Examination (MMSE) score of 27.83 (SD = 2.09). Independent sample t-tests showed that HF patients performed worse than healthy adults on the driving simulation scenario. Finally, partial correlations showed worse attention/executive and motor function were independently associated with poorer driving simulation performance across several indices reflective of driving ability (i.e., centerline crossings, number of collisions, % of time over the speed limit, among others).

CONCLUSION

The current findings showed that reduced cognitive function was associated with poor simulated driving performance in older adults with HF. If replicated using behind-the-wheel testing, HF patients may be at elevated risk for unsafe driving and routine driving evaluations in this population may be warranted.

Driving assessment for maintaining mobility and safety in drivers with dementia

BACKGROUND

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

PRIMARY OBJECTIVES

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

SECONDARY OBJECTIVE

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Executive function and activities of daily living in Alzheimer's disease: a correlational meta-analysis

BACKGROUND

The assessment of executive function (EF) and activities of daily living (ADL) are important elements in the diagnosis of Alzheimer's disease.

METHODS

Following a comprehensive search in three databases, a random-effects meta-analysis was used to investigate the association between ADL ability and seventeen tests of EF, three tests of attention and working memory and the Mini-Mental State Examination. The association between EF and ADL ability was further investigated in relation to four different methods of assessing ADL, and one specific ADL, driving.

RESULTS

Forty-nine studies met the inclusion criteria, and a total of 3,663 participants were included, the majority of whom were diagnosed with Alzheimer's disease. Most of the individual tests, including commonly used tests of EF such as the Clock Drawing Test, Letter Fluency and the Trail Making Test Part B, showed a significant moderate association with ADL. Associations between EF and ADL ability were similar for all four methods of assessing ADL ability. Driving ability was also moderately associated with EF.

CONCLUSION

The meta-analysis suggests a consistent moderate association between ADL and EF, supporting the growing evidence for a link between ADL and executive dysfunction in early dementia.

Investigating driving behaviour of older drivers with mild cognitive impairment using a portable driving simulator

While there is a large body of research indicating that individuals with moderate to severe dementia are unfit to drive, relatively little is known about the driving performance of older drivers with mild cognitive impairment (MCI). The aim of the current study was to examine the driving performance of older drivers with MCI on approach to intersections, and to investigate how their healthy counterparts perform on the same driving tasks using a portable driving simulator. Fourteen drivers with MCI and 14 age-matched healthy older drivers (aged 65-87 years) completed a 10-min simulator drive in an urban environment. The simulator drive consisted of stop-sign controlled and signal-controlled intersections. Drivers were required to stop at the stop-sign controlled intersections and to decide whether or not to proceed through a critical light change at the signal-controlled intersections. The specific performance measures included; approach speed, number of brake applications on approach to the intersection (either excessive or minimal), failure to comply with stop signs, and slower braking response times on approach to a critical light change. MCI patients in our sample performed more poorly than controls across a number of variables. However, because the trends failed to reach statistical significance it will be important to replicate the study using a larger sample to qualify whether the results can be generalised to the broader population.

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

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

The influence of cognitive impairment with no dementia on driving restriction and cessation in older adults

Cognitively impaired older adults may be at increased risk of unsafe driving. Individuals with insight into their own impairments may minimize their risk by restricting or stopping driving. The purpose of this study was to examine the influence of cognitive impairment on driving status and driving habits and intentions. Participants were classified as cognitively impaired, no dementia single (CIND-single), CIND-multiple, or not cognitively impaired (NCI) and compared on their self-reported driving status, habits, and intentions to restrict or quit driving in the future. The groups differed significantly in driving status, but not in whether they restricted their driving or reduced their driving frequency. CIND-multiple group also had significantly higher intention to restrict/stop driving than the NCI group. Reasons for restricting and quitting driving were varied and many individuals reported multiple reasons, both external and internal, for their driving habits and intentions. Regardless of cognitive status, none of the current drivers were seriously thinking of restricting or quitting driving in the next 6 months. It will be important to determine, in future research, how driving practices change over time and what factors influence decisions to restrict or stop driving for people with cognitive impairment.

Dual-task effects of simulated lane navigation and story recall in older adults with and without memory impairment

While driving is a complex task, it becomes relatively automatic over time although unfamiliar situations require increased cognitive effort. Much research has examined driving risk in cognitively impaired elders and found little effect. This study assessed whether mildly memory impaired elders made disproportionate errors in driving or story recall, under simultaneous simulated driving and story recall. Forty-six healthy (61% women; mean age = 76.4) and 15 memory impaired (66% women, mean age = 79.4) elders participated. Cognitive status was determined by neuropsychological performance. Results showed that during dual-task conditions, participants stayed in lane more, and recalled stories more poorly, than when they did the tasks separately. Follow-up analysis revealed that verbatim recall, in particular, was reduced while driving for healthy participants. While memory impaired participants performed more poorly than healthy controls on both tasks, cognitive status was not associated with greater dual-task costs when driving and story recall were combined.

Do Complex Models Increase Prediction of Complex Behaviours? Predicting Driving Ability in People with Brain Disorders

Prediction of complex behavioural tasks via relatively simple modelling techniques, such as logistic regression and discriminant analysis, often has limited success. We hypothesized that to more accurately model complex behaviour, more complex models, such as kernel-based methods, would be needed. To test this hypothesis, we assessed the value of six modelling approaches for predicting driving ability based on performance on computerized sensory–motor and cognitive tests ( SMCTests™) in 501 people with brain disorders. The models included three models previously used to predict driving ability (discriminant analysis, DA; binary logistic regression, BLR; and nonlinear causal resource analysis, NCRA) and three kernel methods (support vector machine, SVM; product kernel density, PK; and kernel product density, KP). At the classification level, two kernel methods were substantially more accurate at classifying on-road pass or fail (SVM 99.6%, PK 99.8%) than the other models (DA 76%, BLR 78%, NCRA 74%, KP 81%). However, accuracy decreased substantially for all of the kernel models when cross-validation techniques were used to estimate prediction of on-road pass or fail in an independent referral group (SVM 73–76%, PK 72–73%, KP 71–72%) but decreased only slightly for DA (74–75%) and BLR (75–76%). Cross-validation of NCRA was not possible. In conclusion, while kernel-based models are successful at modelling complex data at a classification level, this is likely to be due to overfitting of the data, which does not lead to an improvement in accuracy in independent data over and above the accuracy of other less complex modelling techniques.

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".

Different models for predicting driving performance in people with brain disorders

Data from performance on a computerized battery of driving-related sensory-motor and cognitive tests (SMCTests™) were used to predict outcome on a blinded on-road driving assessment in 501 people with brain disorders. Six modelling approaches were assessed: discriminant analysis (DA), binary logistic regression (BLR), nonlinear causal resource analysis (NCRA), and three kernel methods (product kernel density (PK), kernel-product density (KP), and support vector machine (SVM)). At the classification level, the three kernel methods were more accurate for predicting on-road Pass or Fail (SVM 99%, PK 99%, KP 80%) than the other models (DA 75%, BLR 77%, NCRA 66%). However, accuracy decreased substantially across the kernel models when leave-one-out cross-validation was used to estimate how accurately the models would predict on-road Pass or Fail in an independent referral group (SVM 76%, PK 73%, KP 72%) but remained fairly constant for DA (74%) and BLR (76%). Cross-validation of NCRA was not possible. While kernel-based models are successful at modelling complex data at a classification level, this appears to be due to overfitting of the data which does not improve accuracy in an independent data set over and above the accuracy of other modelling techniques.

Factors affecting return to driving post-stroke

BACKGROUND

Stroke can affect a person's ability to drive, an important means of transportation in the developed world.

AIMS

To determine percentage of patients and factors associated with return to driving post-stroke in a service with emphasis on driver assessment.

METHODS

Retrospective study of patients discharged from the Stroke Service of our 470-bed teaching hospital from 1998 to 2002.

RESULTS

Of 72 drivers pre-stroke, 54% recalled a driving assessment and 68% returned to driving. Younger patients (58.6 ± 12.0 vs. 66.5 ± 10.5, p = 0.008) with lower Modified Rankin Score (median 1 vs. 2, p = 0.0001) and normal cognition (55 vs. 43%, p = 0.45) were more likely to resume driving. More patients who were assessed returned to driving than those who were not (74 vs. 61%, p = 0.31).

CONCLUSIONS

A relatively high level of return to driving can be achieved post-stroke with a pro-active approach to driver assessment and rehabilitation. A structured assessment and referral programme should be offered where appropriate.

Prediction of driving ability with neuropsychological tests: demographic adjustments diminish accuracy

Demographically adjusted norms generally enhance accuracy of inferences based on neuropsychological assessment. However, we hypothesized that demographic corrections diminish predictive accuracy for real-world activities with absolute cognitive demands. Driving ability was assessed with a 45-minute drive along a standardized on-road route in participants aged 65+ (24 healthy elderly, 26 probable Alzheimer's disease, 33 Parkinson's disease). Neuropsychological measures included: Trail-Making A and B, Complex Figure, Benton Visual Retention, and Block Design tests. A multiple regression model with raw neuropsychological scores was significantly predictive of driving errors (R2 = .199, p = .005); a model with demographically adjusted scores was not (R2 = .113, p = .107). Raw scores were more highly correlated with driving errors than were adjusted scores for each neuropsychological measure, and among healthy elderly and Parkinson's patients. When predicting real-world activities that depend on absolute levels of cognitive abilities regardless of demographic considerations, predictive accuracy is diminished by demographic corrections.