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

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

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

Investigating feasibility and preliminary efficacy of a simulator-based driving intervention for people with acquired brain injury: A randomised controlled pilot study

OBJECTIVE

To investigate the feasibility and preliminary efficacy of a driving simulator intervention on driving outcomes following acquired brain injury.

DESIGN

Pilot randomised controlled trial.

SETTING

Occupational therapy driver assessment and rehabilitation service.

SUBJECTS

Individuals post-acquired brain injury aiming to return to driving.

INTERVENTION

Eight sessions of simulated driver training over four weeks, in addition to usual care. Control: Usual care only.

MAIN MEASURES

Feasibility outcomes: Participant recruitment and retention; data completeness; therapy attendance and fidelity; adverse events. Performance outcomes: on-road driving performance; Simulator Sickness Questionnaire; Brain Injury Driving Self-Awareness Measure and Driving Comfort Scale - Daytime, assessed at baseline and five weeks post-randomisation.

RESULTS

Out of 523 individuals screened, 22 (4%) were recruited and randomised, with 20 completing their allocated group (n = 12 Simulator, n = 8 Usual Care). For those who completed training, session attendance was 100% with simulator sickness rated, on average, as mild. Six individuals (50%) in the Simulator group failed the on-road assessment, versus two (25%) in the Usual Care group (P = 0.373). On average, the Simulator group reported a positive change in confidence ratings (M = 5.77, SD = 13.96) compared to the Usual Care group, who reported a negative change (M = -6.97, SD = 8.47), P = 0.034. The Simulator group (M = 0.67, SD = 3.34) demonstrated no significant change in self-awareness relative to the Usual Care group (M = -0.83, SD = 1.83, P = 0.325).

CONCLUSIONS

With adjustments to inclusion criteria and recruitment strategies, it may be feasible to deliver the intervention and conduct a larger trial. There is potential benefit of simulator training for improving driver confidence after acquired brain injury.

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

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

Changes in older drivers' self-awareness of driving ability over one year

Older drivers' self-awareness of driving ability can prompt self-regulatory behaviors and modifications of their everyday driving performance. To date, studies have yet to examine how older drivers' self-awareness of changes in driving ability over time or identify the characteristics of those who can accurately monitor such changes. 64 older drivers (Age: Mean = 80.0 years, SD = 5.4; male: 70 %) were recruited and categorized into four groups based on the correspondence of changes in their perceived and actual driving ability over one year: 40 % of the participants were accurate in their stable or better driving ability over time, 30 % did not detect their driving performance had worsened and over-estimated their driving ability, and the remainder either accurately detected their performance had worsened or under-estimated their driving performance. No demographic or clinical factors were associated with older drivers' self-awareness of changes in driving ability over time, except the mental processing and executive functioning measured using the Trail Making Tests Part B, showed a marginal effect. Implications for clinical importance are discussed.

Standardized on-road tests assessing fitness-to-drive in people with cognitive impairments: A systematic review

Objective

The on-road assessment is the gold standard because of its ecological validity. Yet existing instruments are heterogeneous and little is known about their psychometric properties. This study identified existing on-road assessment instruments and extracted data on psychometric properties and usability in clinical settings.

Method

A systematic review identified studies evaluating standardized on-road evaluation instruments adapted for people with cognitive impairment. Published articles were searched on PubMed, CINHAL, PsycINFO, Web of Science, and ScienceDirect. Study quality and the level of evidence were assessed using the COSMIN checklist. The collected data were synthetized using a narrative approach. Usability was subjectively assessed for each instrument by extracting information on acceptability, access, cost, and training.

Results

The review identified 18 published studies between 1994 and 2016 that investigated 12 different on-road evaluation instruments: the Performance-Based Driving Evaluation, the Washington University Road Test, the New Haven, the Test Ride for Practical Fitness to Drive, the Rhode Island Road Test, the Sum of Manoeuvres Score, the Performance Analysis of Driving Ability, the Composite Driving Assessment Scale, the Nottingham Neurological Driving Assessment, the Driving Observation Schedule, the Record of Driving Errors, and the Western University’s On-road Assessment. Participants were mainly male (64%), between 48 and 80 years old, and had a broad variety of cognitive disorders. Most instruments showed reasonable psychometric values for internal consistency, criterion validity, and reliability. However, the level of evidence was poor to support any of the instruments given the low number of studies for each.

Conclusion

Despite the social and health consequences of decisions taken using these instruments, little is known about the value of a single evaluation and the ability of instruments to identify expected changes. None of the identified on-road evaluation instruments seem currently adapted for clinical settings targeting rehabilitation and occupational priorities rather than road security alone.

Study registration

PROSPERO registration number CRD42018103276.

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.

User experiences and perspectives of a driving simulator intervention for individuals with acquired brain injury: A qualitative study

Driving a motor vehicle is a common rehabilitation goal following acquired brain injury (ABI). There is increasing interest in the use of driving simulators for driver rehabilitation post-ABI; however, there is still limited research demonstrating efficacy and acceptability. This study sought to examine the user experience of a driving simulator intervention for ABI survivors. Semi-structured interviews were conducted with 14 individuals, including 12 ABI survivors (42% male; Mean age = 53.92 years, SD age = 17.63) who completed the intervention, and 2 occupational therapist driver assessors who facilitated the intervention. Thematic analysis was adopted to analyse interview data. Findings suggest that individual differences (e.g., anxiety, previous experience) influenced participant response to training. The intervention allowed participants to practise various driving skills, re-familiarize themselves with the task of driving, and prepare for return to on-road driving within a safe environment. The intervention was perceived to be useful for enhancing driver self-awareness, autonomy, confidence and patience. Fidelity and simulator sickness were considered limitations of the simulator technology. Subjective accounts of the appropriateness of intervention components are also documented. Overall, the simulator intervention was reported to be a positive experience for participants. Themes emerging from this study can inform future driving simulator interventions for ABI survivors.

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.

Speeding and Speed Modification of Older Drivers: Does Vehicle Type Make a Difference?

The purpose of this study was to examine whether vehicle type based on size (car vs. other = truck/van/SUV) had an impact on the speeding, acceleration, and braking patterns of older male and female drivers (70 years and older) from a Canadian longitudinal study. The primary hypothesis was that older adults driving larger vehicles (e.g., trucks, SUVs, or vans) would be more likely to speed than those driving cars. Participants (n = 493) had a device installed in their vehicles that recorded their everyday driving. The findings suggest that the type of vehicle driven had little or no impact on per cent of time speeding or on the braking and accelerating patterns of older drivers. Given that the propensity for exceeding the speed limit was high among these older drivers, regardless of vehicle type, future research should examine what effect this behaviour has on older-driver road safety.

Interrater reliability of Western University's on-road assessment

BACKGROUND

Little empirical support exists for interrater reliability between evaluators from different backgrounds when assessing on-road outcomes of drivers.

PURPOSE

We quantified interrater reliability of on-road outcomes between a certified driving school instructor (DI) and an occupational therapist and certified driver rehabilitation specialist (CDRS).

METHOD

Both raters used the Global Rating Score (GRS) with two levels (pass, fail), the GRS with four levels (pass, pass with recommendations, fail remediable, fail), and the priority error rating score (PERS; most frequently occurring on-road errors in priority order) to assess 35 drivers (age, M = 48.31 years, SD = 9.76 years; 40% male; 86% with multiple sclerosis).

FINDINGS

The DI and occupational therapist CDRS had excellent agreement on the GRS with two levels (κ = .892, p < .0001), GRS with four levels (κ = .952, p < .0001), and the PERS (κ = .847-.902, p < .0001), indicating interrater reliability.

IMPLICATIONS

This research contributes to empirical support for the on-road assessment.

Predictors of older drivers' involvement in high-range speeding behavior

OBJECTIVE

Even small increases in vehicle speed raise crash risk and resulting injury severity. Older drivers are at increased risk of involvement in casualty crashes and injury compared to younger drivers. However, there is little objective evidence about older drivers' speeding. This study investigates the nature and predictors of high-range speeding among drivers aged 75-94 years.

METHODS

Speed per second was estimated using Global Positioning System devices installed in participants' vehicles. High-range speeding events were defined as traveling an average 10+km/h above the speed limit over 30 seconds. Descriptive analysis examined speeding events by participant characteristics and mileage driven. Regression analyses were used to examine the association between involvement in high-range speeding events and possible predictive factors.

RESULTS

Most (96%, 182/190) participants agreed to have their vehicle instrumented, and speeding events were accurately recorded for 97% (177/182) of participants. While 77% (136/177) of participants were involved in one or more high-range events, 42% (75/177) were involved in greater than five events during 12-months of data collection. Participants involved in high-range events drove approximately twice as many kilometres as those not involved. High-range events tended to be infrequent (median = 6 per 10,000 km; IQR = 2-18). The rate of high-range speeding was associated with better cognitive function and attention to the driving environment.

CONCLUSION

This suggests those older drivers with poorer cognition and visual attention may drive more cautiously, thereby reducing their high-range speeding behavior.

Assessment of Drivers with Alzheimer's Disease in High Demand Driving Situations: Coping with Intersections in a Driving Simulator

Intersections are one of the most complex and cognitively demanding driving situations. Individuals with dementia and, more precisely, Alzheimer's disease (AD), may face additional challenges negotiating intersections given the nature of their cognitive decline, which often includes deficits of attention. We developed a comprehensive evaluation scheme to assess simulated driving performance at intersections. The evaluation scheme captured all types of errors that could occur during preparation (i.e., prior to the intersection), execution (i.e., during the intersection), and recovery (i.e., after the intersection). Using the evaluation scheme, intersection behaviour in a driving simulator among 17 drivers with mild AD was compared to that of 21 healthy controls. The results indicated that across all types of intersections, mild AD drivers exhibited a greater number of errors relative to controls. Drivers with mild AD made the most errors during the preparation period leading up to the intersection. These findings present a novel approach to analyzing intersection behaviour and contribute to the growing body of research on dementia and driving.

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

Cette étude a examiné une cohorte de 227 conducteurs âgés et a étudié la relation entre leur performance sur la grille d’observation e-DOS pour manœuvres de conduite et (1) les caractéristiques des conducteurs; (2) les capacités fonctionnelles; (3) les perceptions des capacités et le confort pendant la conduite, ainsi que (4) les restrictions auto-déclarées de la conduite. Les participants (hommes: 70%; âge: M = 81.53 ans, É-T = 3,37 ans) a achevé une série de mesures de la capacité fonctionnelle et d’écailles sur le confort, les capacités et les restrictions aperçut du Candrive / Ozcandrive protocole d’évaluation Année 2, avec une tâche de conduite e-DOS. Les observations des comportements de conduite des participants au cours de la tâche de conduite ont été enregistrées pour : la négociation au carrefour, le changement de voie, la fusion, les manœuvres à basse vitesse, et la conduite sans manoeuvres. Les scores de conduite e-DOS étaient élevés (M = 94,74; É-T = 5,70) et étaient liés d’une façon significative aux capacité de conduite perçu des participants, la fréquence rapporté de la conduite dans des situations difficiles, et le nombre de restrictions de la conduite. Les analyses futures exploreront les changements potentiels dans les scores de tâches de conduite au fil du temps.

Determining fitness to drive among drivers with Alzheimer’s disease or cognitive decline

Introduction

Fitness to drive skills progressively deteriorate following a diagnosis of Alzheimer’s disease/cognitive decline. Occupational therapists require standardised assessments to help them make recommendations to clients and licensing authorities regarding client fitness to drive. This research aimed to determine whether drivers in the early stages of Alzheimer’s disease/cognitive decline can drive safely, and if this could be predicted using the occupational therapy – driver off-road assessment battery (OT-DORA Battery).

Method

Drivers with Alzheimer’s disease/cognitive decline were assessed by one of nine driver assessors over 18 months. Client data were collected on the OT-DORA Battery and following on-road assessment; the outcome was recorded as pass, pass with conditions, or fail.

Results

A total of 63 clients were assessed, and n  =  40 (63.5%) were passed as fit to drive, of whom 33(83%) had at least one condition placed on their licence. Client age and scores on four subtests of the OT-DORA Battery were predictive of outcome.

Conclusion

A diagnosis of Alzheimer’s disease/cognitive decline should not automatically preclude driving. Scores on four of the subtests from the OT-DORA Battery may be used to help determine whether a client is fit to drive or not fit to drive, or whether a client should be referred for specialist occupational therapy driver assessment.

Car Licensing Trends of the Babyboomer Cohort (b. 1946-1965) Compared to Earlier Birth Cohorts: Effects on the Driving Population in the State of Victoria, Australia

OBJECTIVE

The objective of this article was to explore trends in licensing among babyboomer older drivers in the state of Victoria, Australia. The study aims were to (1) compare the car licensing trends of the babyboomer cohort to that of previous birth cohorts and (2) predict the number of babyboomers licensed to drive a car in 2021 when the babyboomer cohort reaches an average age of 65 years.

METHODS

The residential population of Victoria, Australia, for 2001-2013 was obtained from the Australian Bureau of Statistics; car licensing statistics were obtained from VicRoads. Birth cohorts from 1916 to 1975 were defined in 10-year birth-year intervals. Population size was modeled using logistic regression. License prevalence was modeled using a logit model.

RESULTS

The babyboomer cohort (1946-1965) in Victoria is 1.7 times larger than the cohort before them. At age 60 years, license prevalence among babyboomers was higher than in previous cohorts: 88% in the 1936-1945 cohort vs. 96% in the 1946-1955 cohort. When the babyboomers reach 65 years (average) in 2021, we estimate there to be over twice as many license holders among them than in the preceding cohort (n = 1,300,094 vs. 630,830, respectively).

CONCLUSIONS

Aging of the babyboomer cohort will have a greater impact on the driving population than on the general population, due to the multiplicative effect of cohort size and license prevalence. The impact of road user aging on burden of injury can be minimized by focusing prevention at crashes typical to older drivers, such as intersection crashes, and promoting car safety features among older drivers.

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.

Examining physiological responses across different driving maneuvers during an on-road driving task: a pilot study comparing older and younger drivers

OBJECTIVE

This pilot study aimed to investigate physiological responses during an on-road driving task for older and younger drivers.

METHODS

Five older drivers (mean age = 74.60 years [2.97]) and 5 younger drivers (mean age = 30.00 years [3.08]) completed a series of cognitive assessments (Montreal Cognitive Assessment [MoCA], Mini Mental Status Examination [MMSE]; Trail Making Test [Trails A and Trails B]) and an on-road driving task along a predetermined, standardized urban route in their own vehicle. Driving performance was observed and scored by a single trained observer using a standardized procedure, where driving behaviors (appropriate and inappropriate) were scored for intersection negotiation, lane changing, and merging. During the on-road driving task, participants' heart rate (HR) was monitored with an unobtrusive physiological monitor.

RESULTS

Younger drivers performed significantly better on all cognitive assessments compared to older drivers (MoCA: t(8) = 3.882, P <.01; MMSE: t(8) = 2.954, P <.05; Trails A: t(8) = -2.499, P <.05; Trails B: t(8) = -3.262, P <.05). Analyses of participants' performance during the on-road driving task revealed a high level of appropriate overall driving behavior (M = 87%, SD = 7.62, range = 73-95%), including intersection negotiation (M = 89%, SD = 8.37%), lane changing (M = 100%), and merging (M = 53%, SD = 28.28%). The overall proportion of appropriate driving behavior did not significantly differ across age groups (younger drivers: M = 87.6%, SD = 9.04; older drivers: M = 87.0%, SD = 6.96; t(8) = 0.118, P =.91).

CONCLUSIONS

Although older drivers scored lower than younger drivers on the cognitive assessments, there was no indication of cognitive overload among older drivers based on HR response to the on-road driving task. The results provide preliminary evidence that mild age-related cognitive impairment may not pose a motor vehicle crash hazard for the wider older driver population. To maintain safe mobility of the aging population, further research into the specific crash risk factors in the older driver population is warranted.