Measurement of driving patterns of older adults using data logging devices with and without global positioning system capability

Revision of the driver behavior questionnaire for Chinese drivers' aberrant driving behaviors using naturalistic driving data

The Manchester Driver Behavior Questionnaire (DBQ) is a widely used self-reported measure of aberrant driving behaviors. It provides a standardized way of evaluating drivers' safety awareness and motivation, but the effectiveness of the DBQ's application in different regions can be influenced by culture, social norms, and time period. Several studies have adjusted DBQ items to reflect driver behavior native to particular regions or times, but few have used objective measurements to make proper adjustments. A naturalistic driving study (NDS) provides vehicle kinematic data and in-vehicle videos that objectively capture actual driving behaviors. The gender, age, and driving experience characteristics of aberrant driving behaviors were analyzed, and, based on comparisons between the DBQ self-reported driving behaviors and those observed in the Shanghai, China, NDS, the existing items from the Manchester DBQ were subsequently adjusted. Sixty-two types of real-world aberrant driving behaviors were extracted from 490 valid crash and near crash events observed in the Shanghai NDS. Aberrant driving behavior rates were calculated for individual characteristics (gender, age, and driving experience), and factor rates were calculated based on the three DBQ factor types of violation, error, and lapse. Results revealed that (a) male drivers, drivers in their thirties, and those with three to five years of driving experience demonstrated higher rates of aberrant driving behaviors; and (b) there were weak correlations between observed NDS factor rates and self-reported DBQ scores, and only slight differences among drivers divided by factor rate level (e.g., high violation rate). The questionnaire calibrated for Chinese drivers includes 23 items. Five of the original 24 DBQ items were modified, eight were left unchanged, eleven were deleted, and ten field-observed combined behaviors were added. In addition to the importance of adjusting the DBQ for today's Chinese drivers, this study provides a method for objectively modifying DBQ items in the future in accord with observed driving behaviors in an NDS.

Subjective evaluations of self and others' driving behaviors: A comparative study involving data from drivers in Japan, China, and Vietnam

INTRODUCTION

This study explored the influence of personal attributes on subjectively-reported aggressive driving behaviors, with an emphasis on the inter-influences between subjectively-reported aggressive driving behaviors between self and other individuals. To determine this, a survey was conducted comprising participants' socio-demographic data, information on their history with automotive accidents, and subjective scales to report on the driving behaviors between self and others. More specifically, a four-factor shortened version of the Manchester Driver Behavior Questionnaire was used to collect data on the aberrant driving behaviors of "self" and "others."

METHOD

Participants were recruited from three countries, namely, Japan (1,250 responses), China (1,250), and Vietnam (1,000). This study only considered the "aggressive violations' factor," which was referred to as self-aggressive driving behaviors (SADB) and others' aggressive driving behaviors (OADB). After collecting the data, univariate and bivariate multiple regression models were employed to better understand the response patterns from both scales.

RESULTS

This study found that accident experience had the strongest influence on the reporting of aggressive driving behaviors (followed by education level). However, variation in countries was also found between both the rate of engagement in aggressive driving behavior and its recognition. In this study, highly educated Japanese drivers tended to evaluate others as safe, whereas highly educated Chinese drivers tended to evaluate others as aggressive. This discrepancy can likely be attributed to cultural norms and values. Meanwhile, evaluations from Vietnamese drivers seemed to differ depending on whether they drove cars or bikes, with additional influences as a result of the driving frequency. Furthermore, this study found that it was most difficult to explain the driving behaviors on the "other" scale reported by Japanese drivers.

PRACTICAL APPLICATIONS

These findings can aid policymakers and planners to develop road safety measures that reflect the behaviors of drivers in their respective countries.

The influence of achievement goals on objective driving behavior

Investigating psychological characteristics through self-reported measures (e.g., anger, sensation seeking) and dynamic behaviors through objective measures (e.g., speed, 2D acceleration, GPS position etc.) may allow us to better understand the behavior of at-risk drivers. To assess drivers' motivation, the theoretical framework of achievement goals has been studied recently. These achievement goals can influence the decision-making and behaviors of individuals engaged in driving. The four achievement goals in driving are: seeking to improve or to drive as well as possible (mastery-approach), to outperform other drivers (performance-approach), to avoid driving badly (mastery-avoidance), and to avoid being the worst driver (performance-avoidance). Naturalistic Driving Studies (NDS) provide access to the objective measurements of data not accessible through self-reported measurements (i.e., speed, accelerations, GPS position). Three dynamic criteria have been developed to characterize the behavior of motorists objectively: driving events, time spent above acceleration thresholds (longitudinal and transversal), and the extent of dynamic demands. All these criteria have been measured in different road contexts (e.g., plain). The aim of this study was to examine the predictive role of the four achievement goals on these objective driving behaviors. 266 drivers (96 women, 117 men) took part in the study, and 4 242 482 km was recorded during 8 months. Simultaneously, they completed the Achievement Goals in Driving Questionnaire. The main results highlighted that mastery-approach goals negatively predicted hard braking and the extent of dynamic demands on plain and hilly roads. Mastery-approach goals seem to be the most protective goals in driving. Future research on the promotion of mastery-approach goals in driving may be able to modify the behavior of at-risk drivers.

Modeling of older adults' driving exposure and avoidance using objective driving data in a naturalistic driving study

Older adults in the United States rely heavily on driving their own vehicles to commute to work, shop for groceries, and access public services. To effectively help older adults maintain mobility and independence,we need to better understand how thecognitive, visual functioning, and health declines influence their tendency to self-restrict their driving. The objective of this study is to develop a causal model to examine the effects of age, gender, household status (specifically living alone), physical, cognitive, visual abilities, and health status on older adults' driving mobility in terms of driving exposure and avoidance. Driving exposure was measured by actual driving data, whereas driving avoidance was assessed by both self-report data and actual driving exposure to challenging situations. Structural equation modeling was used to analyze data collectedin the Second Strategic Highway Research Program Naturalistic Driving Study for establishing relationships between the selected factors and mobility. The structural equation model included a total of794 participants aged 65 and over (367 or 46.22%femalesand 427 or 53.78% males). Results indicate that poorer health is associated with less driving exposure; deteriorating cognitive and physical capabilities are associated with more self-reported driving avoidance and less actual driving in challenging situations; visual function is associated with self-reported avoidance; living alone is associated with higher driving exposure in general as well as in challenging situations; self-reported driving avoidance of challenging situations has a negative association with actual driving in those same situations. The final model could be applied to predict older adults' mobility changes according to their age, gender, household status, as well as their visual, physical, cognitive and health status.

Overestimation of self-reported driving exposure: Results from the SHRP2 Naturalistic Driving Study

OBJECTIVES

The accuracy of self-reported driving exposure has questioned the validity of using self-reported mileage to inform research questions. Studies examining the accuracy of self-reported driving exposure compared to objective measures find low validity, with drivers overestimating and underestimating driving distance. The aims of the current study were to (1) examine the discrepancy between self-reported annual mileage and driving exposure the following year and (2) investigate whether these differences depended on age and annual mileage.

METHODS

Two estimates of drivers' self-reported annual mileage collected during vehicle installation (obtained via prestudy questionnaires) and approximated annual mileage driven (based upon Global Positioning System data) were acquired from 3,323 participants who participated in the Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study.

RESULTS

A Wilcoxon signed rank test showed that there was a significant difference between self-reported and annual driving exposure during participation in SHRP 2, with the majority of self-reported responses overestimating annual mileage the following year, irrespective of whether an ordinal or ratio variable was examined. Over 15% of participants provided self-reported responses with over 100% deviation, which were exclusive to participants underestimating annual mileage. Further, deviations in reporting differed between participants who had low, medium, and high exposure, as well as between participants in different age groups.

CONCLUSIONS

These findings indicate that although self-reported annual mileage is heavily relied on for research, such estimates of driving distance may be an overestimate of current or future mileage and can influence the validity of prior research that has utilized estimates of driving exposure.

Prevalence and determinants of driving habits in the oldest old: Results of the multicenter prospective AgeCoDe-AgeQualiDe study

AIM

To present data on the prevalence of driving habits and to identify the determinants of driving habits among the oldest old in Germany.

METHODS

Cross-sectional data were used from the "Study on Needs, health service use, costs and health-related quality of life in a large sample of oldest-old primary care patients (85+)" (AgeQualiDe), including primary care patients aged 85 years and above (n = 549 at FU 9, mean age was 90.3 years; 86-101 years). Driving habits were measured (driving a car; frequency of driving a car and driving duration). Correlates were quantified using widely established scales (e.g., Geriatric Depression Scale, Instrumental Activities of Daily Living Scale). Multiple regression models were used to identify the determinants of driving habits.

RESULTS

Sixteen percent (87 out of 549) drove a car. Among the car-drivers, about 80% drove at least several times a week and about two-thirds drove longer distances (>15 min). Multiple logistic regressions showed that among the oldest old being a male was more likely to be a current driver compared to being a female. Other significant factors were subjective memory impairment, severe visual impairment, functional and cognitive impairment. Correlates of frequency of driving a car and driving duration were further identified.

CONCLUSION

About one in six very old Germans is still a regular car driver. Several determinants of driving habits among the oldest old were identified. Future longitudinal studies are required to clarify the factors leading to changes in driving habits.

Comparison of self-report and objective measures of driving behavior and road safety: A systematic review

INTRODUCTION

This research systematically reviewed the existing literature in regards to studies which have used both self-report and objective measures of driving behavior. The objective of the current review was to evaluate disparities or similarities between self-report and objective measures of driving behavior.

METHODS

Searches were undertaken in the following electronic databases, PsycINFO, PubMed, and Scopus, for peer-reviewed full-text articles that (1) focused on road safety, and (2) compared both subjective and objective measures of driving performance or driver safety. A total of 22,728 articles were identified, with 19 articles, comprising 20 studies, included as part of the review.

RESULTS

The research reported herein suggested that for some behaviors (e.g., driving in stressful situations) there were similarities between self-report and objective measures while for other behaviors (e.g., sleepiness and vigilance states) there were differences between these measurement techniques. In addition, findings from some studies suggested that in-vehicle devices may be a valid measurement tool to assess driving exposure in older drivers.

CONCLUSIONS

Further research is needed to examine the correspondence between self-report and objective measures of driving behavior. In particular, there is a need to increase the number of studies which compare "like with like" as it is difficult to draw comparisons when there are variations in measurement tools used.

PRACTICAL APPLICATIONS

Incorporating a range of objective and self-report measurements tools in research would help to ensure that the methods used offer the most reliable measures of assessing on-road behaviors.

Louis R, Zanier N, Ryan L, LeBlanc D, Smith J, Yung R, Nyquist L, DiGuiseppi C, Li G, Mielenz T, Strogatz D. The effects of demographics, functioning, and perceptions on the relationship between self-reported and objective measures of driving exposure and patterns among older adults

The exploratory study reported here was intended to examine: how strongly subjectively reported driving avoidance behaviors (commonly referred to as self-regulation) and exposure were related to their objectively measured counterparts and whether it depended on the specific behavior; the extent to which gender and age play a role in the association between subjectively reported driving avoidance behaviors and exposure and their objectively measured counterparts; and the extent to which demographics, health and functioning, driving-related perceptions, and cognition influence the association between subjective and objective driving avoidance behaviors overall. The study used data from the Longitudinal Research on Aging Drivers (LongROAD) study, a multisite, prospective cohort study designed to generate empirical data for understanding the role of medical, behavioral, environmental, and technological factors in driving safety during the process of aging. Objective driving measures were derived from GPS/datalogger data from 2131 LongROAD participants' vehicles. The corresponding subjective measures came from a comprehensive questionnaire administered to participants at baseline that asked them to report on their driving exposure, patterns, and other aspects of driving. Several other variables used in the analyses came from the comprehensive questionnaire and an inperson clinical assessment administered to participants at baseline. A series of simple linear and logistic models were fitted to examine the relationship between the subjective and objective driving measures of interest, and a multivariable analysis was conducted to examine the potential role of selected factors in the relationship between objective and subjective driving avoidance behaviors. Results of the models are presented and overall findings are discussed within the context of the existing research literature.

Naturalistic Driving: A Framework and Advances in Using Big Data

Driving is an activity that facilitates physical, cognitive, and social stimulation in older adults, ultimately leading to better physical and cognitive health. However, aging is associated with declines in vision, physical health, and cognitive health, all of which can affect driving ability. One way of assessing driving ability is with the use of sensors in the older adult’s own vehicle. This paper provides a framework for driving assessment and addresses how naturalistic driving studies can assist in such assessments. The framework includes driving characteristics (how much driving, speed, position, type of road), actions and reactions (lane changes, intersections, passing, merging, traffic lights, pedestrians, other vehicles), destinations (variety and distance, sequencing and route planning), and driving conditions (time of day and season). Data from a subset of Ottawa drivers from the Candrive study is used to illustrate the use of naturalistic driving data. Challenges in using naturalistic driving big data and the changing technology in vehicles are discussed.

Using naturalistic driving data to better understand the driving exposure and patterns of older drivers

OBJECTIVE

The aging of the population in the United States and elsewhere has brought increasing attention to the issue of safe driving and mobility among older adults. The overall objective of this research was to use naturalistic data collection to better understand driving exposure and driving patterns, 2 important contributors to crash risk.

METHODS

Data came from a study conducted at the University of Michigan Transportation Research Institute as part of the Integrated Vehicle-Based Safety System (IVBSS) program. A total of 108 randomly sampled drivers took part, with the sample stratified by age and sex. The age groups examined were 20 to 30 (younger), 40 to 50 (middle-aged), and 60 to 70 years old (older). Sixteen late-model Honda Accords were used as research vehicles and were driven by participants as their personal vehicles over the study period. Roughly the first 2 weeks of vehicle use comprised the baseline driving period, during which the IVBSS technologies were turned off (i.e., no warnings were presented to the drivers) but all onboard data were collected. For this article, only data from the baseline period were analyzed to limit any confounding effects that the safety technology may have had on driving behavior.

RESULTS

Results indicated that when looking at age independent of sex, older drivers (age 60-70) took fewer trips, drove fewer minutes, were less likely to drive at night, and had fewer high decelerations and speeding events than the youngest age group (20-30). They were also less likely to drive during peak morning traffic and on high-speed roads than their middle-age counterparts (40-50). Across all age groups, there were few differences by sex, with the exception that females drove fewer miles and fewer minutes and had fewer high decelerations than males. When both age and sex were taken into account, it was often the group of females age 60-70 that appeared to account for many of the age and sex differences found in driving exposure and patterns.

CONCLUSIONS

Future research in this area would benefit from larger scale and longitudinal study designs so that changes in driving exposure and patterns over time among large samples of drivers could be examined.

Identifying compensatory driving behavior among older adults using the situational avoidance questionnaire

INTRODUCTION

Driving self-regulation is considered a means through which older drivers can compensate for perceived declines in driving skill or more general feelings of discomfort on the road. One form of driving self-regulation is situational avoidance, the purposeful avoidance of situations perceived as challenging or potentially hazardous. This study aimed to validate the Situational Avoidance Questionnaire (SAQ, Davis, Conlon, Ownsworth, & Morrissey, 2016) and identify the point on the scale at which drivers practicing compensatory avoidance behavior could be distinguished from those whose driving is unrestricted, or who are avoiding situations for other, non-compensatory reasons (e.g., time or convenience).

METHOD

Seventy-nine Australian drivers (M_age=71.48, SD=7.16, range: 55 to 86years) completed the SAQ and were classified as a compensatory-restricted or a non-restricted driver based on a semi-structured interview designed to assess the motivations underlying avoidance behavior reported on the SAQ.

RESULTS

Using receiver-operator characteristic (ROC) analysis, the SAQ was found to have high diagnostic accuracy (sensitivity: 85%, specificity: 82%) in correctly classifying the driver groups. Group comparisons confirmed that compensatory-restricted drivers were self-regulating their driving behavior to reduce the perceived demands of the driving task. This group had, on average, slower hazard perception reaction times, and reported greater difficulty with driving, more discomfort when driving due to difficulty with hazard perception skills, and greater changes in cognition over the past five years.

CONCLUSIONS

The SAQ is a psychometrically sound measure of situational avoidance for drivers in baby boomer and older adult generations.

PRACTICAL APPLICATIONS

Use of validated measures of driving self-regulation that distinguish between compensatory and non-compensatory behavior, such as the SAQ, will advance our understanding of the driving self-regulation construct and its potential safety benefits for older road users.

A validation study comparing self-reported travel diaries and objective data obtained from in-vehicle monitoring devices in older drivers with bilateral cataract

BACKGROUND

Advances in technology have made it possible to examine real-world driving using naturalistic data obtained from in-vehicle monitoring devices. These devices overcome the weaknesses of self-report methods and can provide comprehensive insights into driving exposure, habits and practices of older drivers.

AIM

The aim of this study is to compare self-reported and objectively measured driving exposure, habits and practices using a travel diary and an in-vehicle driver monitoring device in older drivers with bilateral cataract.

METHODS

A cross-sectional study was undertaken. Forty seven participants aged 58-89 years old (mean=74.1; S.D.=7.73) were recruited from three eye clinics over a one year period. Data collection consisted of a cognitive test, a researcher-administered questionnaire, a travel diary and an in-vehicle monitoring device. Participants' driving exposure and patterns were recorded for one week using in-vehicle monitoring devices. They also completed a travel diary each time they drove a motor vehicle as the driver. Paired t-tests were used to examine differences/agreement between the two instruments under different driving circumstances.

RESULTS

The data from the older drivers' travel diaries significantly underestimated the number of overall trips (p<0.001), weekend trips (p=0.002) and trips during peak hour (p=0.004). The travel diaries also significantly overestimated overall driving duration (p<0.001) and weekend driving duration (p=0.003), compared to the data obtained from the in-vehicle monitoring devices. No significant differences were found between instruments for kilometres travelled under any of the driving circumstances.

CONCLUSIONS

The results of this study found that relying solely on self-reported travel diaries to assess driving outcomes may not be accurate, particularly for estimates of the number of trips made and duration of trips. The clear advantages of using in-vehicle monitoring devices over travel diaries to monitor driving habits and exposure among an older population are evident.

Young drivers' responses to anti-speeding advertisements: Comparison of self-report and objective measures of persuasive processing and outcomes

OBJECTIVE

Self-report measures are typically used to assess the effectiveness of road safety advertisements. However, psychophysiological measures of persuasive processing (i.e., skin conductance response [SCR]) and objective driving measures of persuasive outcomes (i.e., in-vehicle Global Positioning System [GPS] devices) may provide further insights into the effectiveness of these advertisements. This study aimed to explore the persuasive processing and outcomes of 2 anti-speeding advertisements by incorporating both self-report and objective measures of speeding behavior. In addition, this study aimed to compare the findings derived from these different measurement approaches.

METHODS

Young drivers (N = 20, M age = 21.01 years) viewed either a positive or negative emotion-based anti-speeding television advertisement. While viewing the advertisement, SCR activity was measured to assess ad-evoked arousal responses. The RoadScout GPS device was then installed in participants' vehicles for 1 week to measure on-road speed-related driving behavior. Self-report measures assessed persuasive processing (emotional and arousal responses) and actual driving behavior.

RESULTS

There was general correspondence between the self-report measures of arousal and the SCR and between the self-report measure of actual driving behavior and the objective driving data (as assessed via the GPS devices).

CONCLUSIONS

This study provides insights into how psychophysiological and GPS devices could be used as objective measures in conjunction with self-report measures to further understand the persuasive processes and outcomes of emotion-based anti-speeding advertisements.

Seasonal and Weather Effects on Older Drivers' Trip Distances

The purpose of this study was to determine if season or weather affected the objectively measured trip distances of older drivers (≥ 70 years; n = 279) at seven Canadian sites. During winter, for all trips taken, trip distance was 7 per cent shorter when controlling for site and whether the trip occurred during the day. In addition, for trips taken within city limits, trip distance was 1 per cent shorter during winter and 5 per cent longer during rain when compared to no precipitation when controlling for weather (or season respectively), time of day, and site. At night, trip distance was about 30 per cent longer when controlling for season and site (and weather), contrary to expectations. Together, these results suggest that older Canadian drivers alter their trip distances based on season, weather conditions, and time of day, although not always in the expected direction.

Seat belt use and fit among drivers aged 75 years and older in their own vehicles

OBJECTIVE

This article aims to describe seat belt wearing patterns and quality of seat belt fit among drivers aged 75 years and older. A secondary aim is to explore associations between body shape, comfort, and seat belt use patterns.

METHODS

This is an observation and survey study of a cohort of 380 drivers aged 75 years and over. During home visits, photographs were taken of the drivers in their vehicles for later analysis of belt fit and a short survey was also administered to collect demographic data and information about seat belt use and comfort. Seat belt fit and use of belt and seat accessories were analyzed from the photographs.

RESULTS

Data from 367 participants with photographs were analyzed. Whereas 97% reported using a seat belt and 90% reported their seat belt to be comfortable, 21% reported repositioning their seat belt to improve comfort. Good sash and lap belt fit were achieved in 53 and 59% of participants, respectively, but only 35% achieved overall good fit. Both poor sash and lap belt fit were observed in 23% of participants. Drivers who were in the obese category had over twice the odds (95% confidence interval [CI], 1.2-4.1) of having a poor lap belt fit than those in the normal body mass index [BMI] range, and drivers who were overweight had 1.8 times the odds (95% CI, 1.1-2.9) of having poor lap belt fit. Older females also had twice the odds (95% CI, 1.3-3.5) of poor lap belt fit compared to older males, regardless of BMI. Sash belt fit did not vary significantly by BMI, stature, or gender. However older drivers who reported that they had not made any adjustments to the D-ring height had 1.7 times the odds of having poor sash belt fit than those who made adjustments (1.2-2.9). Females were 7.3 times more likely to report comfort problems than males (95% CI, 3.2, 16.3) but there was no association between reported comfort and BMI or seat belt fit. Drivers who reported comfort problems had 6 times the odds (3.2-13.6) of also reporting active repositioning of the belt.

CONCLUSIONS

The results suggest that older drivers face challenges in achieving comfortable and correct seat belt fit. This may have a negative impact on crash protection. Belt fit problems appear to be associated with body shape, particularly high BMI and gender. There is a need for further investigation of comfort accessories; in the interim, older drivers and occupants should be encouraged to use features such as D-ring adjusters to improve sash belt fit.

Self-regulation of older drivers with cognitive impairment: a systematic review

BACKGROUND

Cognitive decline contributes significantly to the safety risk of older drivers. Some drivers may be able to compensate for the increased crash risk by avoiding complex driving situations or restricting their driving.

OBJECTIVE AND METHOD

A comprehensive English-language systematic review was conducted to determine the level of evidence for older adult drivers with cognitive impairment engaging in self-regulation.

RESULTS

Twelve studies were included in the review. The majority of studies investigated driver avoidance, followed by driver restriction. Few studies ascertained the reasons for changing driving behaviour.

CONCLUSIONS

The evidence supports the view that drivers with cognitive impairment do restrict their driving and avoid complex driving situations. However, it remains to be determined whether the drivers who engage in self-regulation have insight into their own driving abilities or whether external factors result in self-regulation of driving behaviour.

CAN INTERMITTENT VIDEO SAMPLING CAPTURE INDIVIDUAL DIFFERENCES IN NATURALISTIC DRIVING?

We examined the utility and validity of intermittent video samples from black box devices for capturing individual difference variability in real-world driving performance in an ongoing study of obstructive sleep apnea (OSA) and community controls. Three types of video clips were coded for several dimensions of interest to driving research including safety, exposure, and driver state. The preliminary findings indicated that clip types successfully captured variability along targeted dimensions such as highway vs. city driving, driver state such as distraction and sleepiness, and safety. Sleepiness metrics were meaningfully associated with adherence to PAP (positive airway pressure) therapy. OSA patients who were PAP adherent showed less sleepiness and less non-driving related gaze movements than nonadherent patients. Simple differences in sleepiness did not readily translate to improvements in driver safety, consistent with epidemiologic evidence to date.

The Canadian Safe Driving Study-Phase I pilot: Examining potential logistical barriers to the full cohort study

Multiple organizations and task forces have called for a reliable and valid method to identify older drivers who are medically unfit to drive. The development of a clinical decision rule for this type of screening requires data from a longitudinal prospective cohort of older drivers. The aim of this article is to identify potential design, sampling and data collection barriers to such studies based on an analysis of the Canadian Safe Driving Study-phase I pilot (Candrive I). A convenience sample of 100 active older drivers aged 70 years or more was recruited through the aid of a seniors' organization, 94 of whom completed the full study (retention rate 94%). Data were collected over the course of 1 year on various driving behaviours, as well as on cognitive, physical and mental functioning. Driving patterns were recorded using driving diaries, logs and electronic devices. Driving records from the Ministry of Transportation of Ontario (MTO) were obtained for the 3-year period preceding the study initiation and up to 1 year following study completion. An increased burden of illness was observed as the number of medical diagnoses and medication use increased over the study period. Study participants were involved in a total of five motor vehicle collisions identified through MTO records, which was comparable to the Ontario annual collision rate of 4.1% for drivers aged 75 years or older. In sum, many of the relevant logistical and practical barriers to studying a large sample of older drivers longitudinally have been shown to be addressable, supporting the feasibility of completing a large prospective cohort study of older drivers.

Self-rated driving habits among older adults with clinically-defined mild cognitive impairment, clinically-defined dementia, and normal cognition

Older adults with clinically-defined dementia may report reducing their driving more than cognitively normal controls. However, it is unclear how these groups compare to individuals with clinically-defined mild cognitive impairment (MCI) in terms of driving behaviors. The current study investigated self-reported driving habits among adults age 60 and older with clinical MCI (n=41), clinical mild dementia (n=40), and normal cognition (n=43). Participants reported their driving status, driving frequency (days per week), and how often they avoided accessing the community, making left turns, driving at night, driving in unfamiliar areas, driving on high-traffic roads, and driving in bad weather. After adjusting for education, a MANCOVA revealed that participants with MCI and dementia avoided unfamiliar areas and high-traffic roads significantly more than normal participants. Participants with dementia also avoided left turns and accessing the community more than those with normal cognition and MCI (p<0.05 for all). The other driving variables did not significantly differ between groups. Thus, older adults with clinically-defined MCI, as well as those with dementia, avoided some complex driving situations more than cognitively intact adults. However, all diagnostic groups had similar rates of driving cessation and frequency. Future research should examine the safety implications of such findings.

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

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

Determining the validity of the AMA guide: A historical cohort analysis of the assessment of driving related skills and crash rate among older drivers

BACKGROUND

Chronic health conditions associated with ageing can lead to changes in driving ability. The Canadian Driving Research Initiative for Vehicular Safety in the Elderly (Candrive II) is a 5-year prospective study funded by the Canadian Institutes of Health Research aiming to develop an in-office screening tool that will help clinicians identify potentially at-risk older drivers. Currently, no tools exist to directly predict the risk of motor vehicle collision (MVC) in this population. The American Medical Association (AMA), in collaboration with the National Highway Traffic Safety Association, has designed an opinion-based guide for assessing medical fitness to drive in older adults and recommends that physicians use the Assessment of Driving Related Skills (ADReS) as a test battery to measure vision, cognition and motor/somatosensory functions related to driving. The ADReS consists of the Snellen visual acuity test, visual fields by confrontation test, Trail Making Test part B, clock drawing test, Rapid Pace Walk, and manual tests of range of motion and motor strength. We used baseline data from the Candrive/Ozcandrive common cohort of older drivers to evaluate the validity of the ADReS subtests. We hypothesized that participants who crashed in the 2 years before the baseline assessment would have poorer scores on the ADReS subtests than participants who had not crashed.

METHODS

In the Candrive/Ozcandrive study, 1230 participants aged 70 years or older were recruited from 7 Canadian cities, 1 Australian city and 1 New Zealand city, all of whom completed a comprehensive clinical assessment at study entry. The assessment included all tests selected as part of the ADReS. For this historical cohort study, data on all crashes (at-fault and non-at-fault) that occurred within 2 years preceding the baseline assessment were obtained from the respective licensing jurisdictions. Those who crashed were compared to those who had not crashed on their ADReS subtest scores using Pearson's chi-squared test and Student's t-test.

RESULTS

Sixty-three of the 1230 participants (5.1%) were involved in an MVC within the 2 years preceding the baseline assessment. Contrary to our hypothesis, there were no statistically significant associations between abnormal performance on the tests constituting the ADReS and history of crash in the previous 2 years (p>0.01).

DISCUSSION

We found that a history of crash in the previous 2 years was not associated with abnormalities on the subtests comprising the ADReS. This suggests the need for prospective analyses of risk factors over time to establish sensitive, valid predictors of crash that can be incorporated in clinical practice guidelines.

Effect of cognitive status on self-regulatory driving behavior in older adults: an assessment of naturalistic driving using in-car video recordings

Previous findings that older drivers engage in strategic self-regulatory behaviors to minimize perceived safety risks are primarily based on survey reports rather than actual behavior. This study analyzed in-car video recording of naturalistic driving of 18 patients with Alzheimer disease (AD) and 20 age-matched controls in order to (1) characterize self-regulatory behaviors engaged by older drivers and (2) assess how behaviors change with cognitive impairment. Only participants who were rated "safe" on a prior standardized road test were selected for this study. Both groups drove primarily in environments that minimized the demands on driving skill and that incurred the least risk for involvement in major crashes. Patients with AD displayed further restrictions of driving behavior beyond those of healthy elderly individuals, suggesting additional regulation on the basis of cognitive status. These data provide critical empirical support for findings from previous survey studies indicating an overall reduction in driving mobility among older drivers with cognitive impairment.

Patterns of level and change in self-reported driving behaviors among older adults: who self-regulates?

OBJECTIVES

The present study investigated patterns of self-reported driving habits among healthy older adults over 5 years, as well as characteristics that distinguished subgroups with different patterns.

METHODS

Participants were drivers from the control group of the Advanced Cognitive Training for Independent and Vital Elderly study at the baseline assessment (N = 597). The outcome was a composite of driving frequency, driving space, and perceived driving difficulty. Growth mixture models identified classes of participants with different baseline scores and change trajectories, and classes were compared in terms of baseline sensory, physical, and cognitive functioning.

RESULTS

A 3-class model was indicated, consisting of 2 classes with intercept differences and stability over time, "above-average stable" (39%) and "average stable" drivers (44%), and 1 class with a lower intercept and negative slope, "decreasers" (17%). Relative to stable drivers, decreasers exhibited significantly more depressive symptoms and poorer self-rated health, balance, everyday functioning, and speed of processing after controlling for age and education (p < .05).

DISCUSSION

The majority of older drivers maintained their driving over time at different levels, whereas a subgroup of individuals with poorer baseline functioning self-regulated by reducing their driving. Future studies should determine how such patterns affect driving safety.

Naturalistic Study of Winter Driving Practices by Older Men and Women: Examination of Weather, Road Conditions, Trip Purposes, and Comfort

La plupart des études sur les pratiques de conduite des aînés sont basées sur des données d’autoévaluation ; aucune n’a examiné objectivement leurs habitudes de conduite hivernale. Nous avons utilisé des appareils électroniques associés à des journaux de voyages, des cartes numériques et des archives météorologiques, afin d’examinerétudier les modes de conduite des personnes âgées de 65 à 91 sur deux semaines consécutives entre novembre 2008 et mars 2009. La conduite de nuit différait selon le mois, montrant l’importance des facteurs saisonniers, en particulier la quantité de lumière du jour. Bien que 69 pour cent de notre échantillon ait conduit les jours de mauvais temps, les aînés ont montré être significativement plus susceptibles de faire des voyages à des fins sociales ou de divertissement les jours de beau temps, et ils ont entrepris des voyages plus longs les jours offrant de bonnes conditions routières. Les scores de confort de conduite, notamment pour la conduite de nuit, étaient liés de manière significative aux indicateurs multiples de l’exposition et des habitudes, y compris au rayon autour du domicile. Comparativement aux hommes, les femmes ont obtenu des scores de conduite significativement plus bas, et ont été moins susceptibles de conduire quand les conditions metéorologiques et routières étaient défavorables.

Correspondence between self-reported and objective measures of driving exposure and patterns in older drivers

The driving behavior of older adults has been traditionally examined using questionnaires and diaries. The accuracy of self-reports has been questioned, and in-vehicle recording devices touted as more objective measures of real-world driving. The purposes of this study were to replicate and extend prior research comparing self-report and actual measures of driving exposure and patterns. Two electronic devices were installed in the vehicles of 61 drivers (67-92 years, 59% women) who were instructed to drive as usual over 1-week. Participants completed trip logs, daily diaries, a questionnaire on usual driving habits, ratings of situational driving frequency and avoidance and a follow-up interview. Only 53% of the sample attempted to estimate how far they had driven over the week and self-estimates were inaccurate (ME=77.5 km; CV=44.5%). Drivers tended to miss a significant number of trips and stops in their diaries. Driving behavior over the week was fairly consistent with usual practices regarding time of day, driving in certain areas, and night driving. However, subjects drove in challenging situations more than usual. Triangulating multiple sources of electronic and self-reported data provided a better understanding about the behavior of older drivers.