Sjaan Koppel

The Candrive/Ozcandrive prospective older driver study: Methodology and early study findings

Although the vast majority of active, older drivers are safe drivers, health conditions and related functional declines associated with increasing age can affect driving ability. This is a concern for older drivers, their families, and the public, as well as government agencies. To address these issues, the Canadian Institutes of Health Research (CIHR) Team in Driving in Older Persons (Candrive II) Research Program was funded in 2008 to create a prospective cohort of older active drivers to be followed for several years. In 2009 an Australian collaboration (Ozcandrive) joined the project funded by an Australian Research Council (ARC) Linkage Grant. This special issue describes the preliminary findings of the Candrive/Ozcandrive prospective study of 1300 older drivers in Canada, Australia and New Zealand. The methodology for the study, description of the cohort and findings related to older driver health and effects on driving, as well as the utility of some existing older driver assessment tools used on this population, are described. Future findings from this ongoing study will lead to insights into older driver safety and tools that will ideally help keep older drivers safely on the road.

Reprint of “Driving avoidance by older adults: Is it always self-regulation?” ☆

Self-regulation shows promise as a means by which older adults can continue to drive at some level without having to stop altogether. Self-regulation is generally described as the process of modifying or adjusting ones driving patterns by driving less or intentionally avoiding driving situations considered to be challenging, typically in response to an awareness that driving skills have declined. However, most studies asking older adults whether they avoid certain driving situations or have reduced the amount of driving they do under certain circumstances have not delved deeper into the motivations for such avoidance or driving reduction. There are many reasons for modifying driving that have nothing to do with self-regulation, such as no longer needing to take trips at certain times of day because of changes in preferences or lifestyles. The purpose of this study was to examine self-regulatory practices among older adults at multiple levels of driver performance and decision making, taking into account the specific motivations for avoiding particular driving situations or engaging in other driving practices. Study participants completed a computer-based questionnaire on driving self-regulation. Results suggest that self-regulation is a complex process that cannot be defined simply by the reported driving modifications made by drivers. Understanding the motivations for these behaviors is necessary and the study showed that they are varied and differ considerably across driving situations. Reasons for driving avoidance or other practices were often more closely related to lifestyle or preferences than to self-regulation. Based on these findings, three distinct groups were identified with regard to whether and for what reasons participants modified their driving.

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

RÉSUMÉ: 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 manoeuvres 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 manoeuvres 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. ABSTRACT: This study examined a cohort of 227 older drivers and investigated the relationship between performance on the electronic Driver Observation Schedule (eDOS) driving task and: (1) driver characteristics; (2) functional abilities; (3) perceptions of driving comfort and abilities; and (4) self-reported driving restrictions. Participants (male: 70%; age: M = 81.53 years, SD = 3.37 years) completed a series of functional ability measures and scales on perceived driving comfort, abilities, and driving restrictions from the Year 2 Candrive/Ozcandrive assessment protocol, along with an eDOS driving task. Observations of participants’ driving behaviours during the driving task were recorded for intersection negotiation, lane-changing, merging, low-speed maneuvers, and maneuver-free driving. eDOS driving task scores were high (M = 94.74; SD = 5.70) and significantly related to participants’ perceived driving abilities, reported frequency of driving in challenging situations, and number of driving restrictions. Future analyses will explore potential changes in driving task scores over time.

Computer vision and driver distraction: Developing a behaviour-flagging protocol for naturalistic driving data

Naturalistic driving studies (NDS) allow researchers to discreetly observe everyday, real-world driving to better understand the risk factors that contribute to hazardous situations. In particular, NDS designs provide high ecological validity in the study of driver distraction. With increasing dataset sizes, current best practice of manually reviewing videos to classify the occurrence of driving behaviours, including those that are indicative of distraction, is becoming increasingly impractical. Current statistical solutions underutilise available data and create further epistemic problems. Similarly, technical solutions such as eye-tracking often require dedicated hardware that is not readily accessible or feasible to use. A computer vision solution based on open-source software was developed and tested to improve the accuracy and speed of processing NDS video data for the purpose of quantifying the occurrence of driver distraction. Using classifier cascades, manually-reviewed video data from a previously published NDS was reanalysed and used as a benchmark of current best practice for performance comparison. Two software coding systems were developed - one based on hierarchical clustering (HC), and one based on gender differences (MF). Compared to manual video coding, HC achieved 86 percent concordance, 55 percent reduction in processing time, and classified an additional 69 percent of target behaviour not previously identified through manual review. MF achieved 67 percent concordance, a 75 percent reduction in processing time, and classified an additional 35 percent of target behaviour not identified through manual review. The findings highlight the improvements in processing speed and correctly classifying target behaviours achievable through the use of custom developed computer vision solutions. Suggestions for improved system performance and wider implementation are discussed.

Understanding fatal older road user crash circumstances and risk factors

ABSTRACT Objective: This study used medicolegal data to investigate fatal older road user (ORU) crash circumstances and risk factors relating to four key components of the Safe System approach (e.g., roads and roadsides, vehicles, road users, and speeds) to identify areas of priority for targeted prevention activity. Methods: The Coroners Court of Victorias Surveillance Database was searched to identify coronial records with at least one deceased ORU in the state of Victoria, Australia, for 2013–2014. Information relating to the ORU, crash characteristics and circumstances, and risk factors was extracted and analyzed. Results: The average rate of fatal ORU crashes per 100,000 population was 8.1 (95% confidence interval [CI] 6.0–10.2), which was more than double the average rate of fatal middle-aged road user crashes (3.6, 95% CI 2.5–4.6). There was a significant relationship between age group and deceased road user type (χ2(15, N = 226) = 3.56, p < 0.001). The proportion of deceased drivers decreased with age, whereas the proportion of deceased pedestrians increased with age. The majority of fatal ORU crashes involved a counterpart (another vehicle: 59.4%; fixed/stationary object: 25.4%), and occurred “on road” (87.0%), on roads that were paved (94.2%), dry (74.2%), and had light traffic volume (38.3%). Road user error was identified by the police and/or coroner for the majority of fatal ORU crashes (57.9%), with a significant proportion of deceased ORU deemed to have “misjudged” (40.9%) or “failed to yield” (37.9%). Conclusions: Road user error was the most significant risk factor identified in fatal ORU crashes, which suggests that there is a limited capacity of the Victorian road system to fully accommodate road user errors. Initiatives related to safer roads and roadsides, vehicles, and speed zones, as well as behavioral approaches, are key areas of priority for targeted activity to prevent fatal older road user crashes in the future.

Frontal and oblique crash tests of HIII 6-year-old child ATD using real-world, observed child passenger postures

ABSTRACT Objective: The aim of this study was to evaluate the consequences of frontal and oblique crashes when positioning a Hybrid III (HIII) 6-year-old child anthropometric test device (ATD) using observed child passenger postures from a naturalistic driving study (NDS). Methods: Five positions for booster-seated children aged 4–7 years were selected, including one reference position according to the FMVSS 213 ATD seating protocol and 4 based on real-world observed child passenger postures from an NDS including 2 user positions with forward tilting torso and 2 that combined both forward and lateral inboard tilting of the torso. Seventeen sled tests were conducted in a mid-sized vehicle body at 64 km/h (European New Car Assessment Programme [Euro NCAP] Offset Deformable Barrier [ODB] pulse), in full frontal and oblique (15°) crash directions. The rear-seated HIII 6-year-old child ATD was restrained on a high-back booster seat. In 10 tests, the booster seat was also attached with a top tether. In the oblique tests, the ATD was positioned on the far side. Three camera views and ATD responses (head, neck, and chest) were analyzed. Results: The shoulder belt slipped off the shoulder in all ATD positions in the oblique test configuration. In full frontal tests, the shoulder belt stayed on the shoulder in 3 out of 9 tests. Head acceleration and neck tension were decreased in the forward leaning positions; however, the total head excursion increased up to 210 mm compared to te reference position, due to belt slip-off and initial forward leaning position. Conclusions: These results suggest that real-world child passenger postures may contribute to shoulder belt slip-off and increased head excursion, thus increasing the risk of head injury. Restraint system development needs to include a wider range of sitting postures that children may choose, in addition to the specified postures of ATDs in seating test protocols, to ensure robust performance across diverse use cases. In addition, these tests revealed that the child ATD is limited in its ability to mimic real-world child passenger postures. There is a need to develop child human body models that may offer greater flexibility for these types of crash evaluations.

Can child restraint product information developed using consumer testing sustain correct use 6 months after child restraint purchase? Study protocol for a cluster randomised controlled trial

Background With long-standing and widespread high rates of errors in child restraint use, there is a need to identify effective methods to address this problem. Information supplied with products at the point of sale may be a potentially efficient delivery point for such a countermeasure. The aim of this study is to establish whether product materials developed using a consumer-driven approach reduce errors in restraint use among purchasers of new child restraint systems. Methods A cluster randomised controlled trial (cRCT) will be conducted. Retail stores (n=22) in the greater Sydney area will be randomised into intervention sites (n=11) and control sites (n=11), stratified by geographical and socioeconomic indicators. Participants (n=836) will enter the study on purchase of a restraint. Outcome measures are errors in installation of the restraint as observed by a trained researcher during a 6-month follow-up home assessment, and adjustment checks made by the parent when the child is placed into the restraint (observed using naturalistic methods). Process evaluation measures will also be collected during the home visit. An intention-to-treat approach will be used for all analyses. Correct use and adjustment checks made by the parent will be compared between control and intervention groups using a logistic regression model. The number of installation errors between groups will be compared using Poisson regression. Discussion This cRCT will determine the effectiveness of targeted, consumer-driven information on actual error rates in use of restraints. More broadly, it may provide a best practice model for developing safety product information. Trial registration number ACTRN12617001252303p; Pre-results.

Fatal road transport crashes among Australian residential aged care facility residents

To examine fatal road transport crashes of residential aged care facility (RACF) residents to determine crash characteristics and risk factors.

PW 1875 Do we already have the answers to prevent deaths on our roads? in-depth analysis of coroners’ recommendations

In Australia, all fatal transport crashes are investigated by Coroners. Detailed information on a range of factors generated for these investigations is not available elsewhere, yet to date, this data and the coroners’ recommendations are not being maximised to inform road safety policy and practice to reduce trauma on the roads. Further, the insights from these investigations are not being shared internationally to benefit road safety efforts globally. This study is a retrospective, descriptive study examining coroners’ recommendations from 2000 to 2017. During that period, there were over 24 000 deaths on Australian roads resulting in more than 2000 coroners’ recommendations to analyse. The recommendations are being examined in terms of: target population; risk/contributing factor; countermeasure; intervention level; implementation strategy; organisation, and; implementation timeframe. Analysis is currently underway. To date, fatalities involving vulnerable road users and heavy vehicle have been examined. In the main, the recommendations related vehicle modification (rear vision camera, warning technology for older style truck cabins with visibility restrictions) and education in relation to driver behaviour and expectation of vulnerable road users as well as public education about safe behaviour around heavy vehicles and visibility restrictions. Analysis is continuing and will include all road user types. Findings from this study will provide a systematic analysis of the medico-legal death investigations conducted for road deaths in Australia. It is anticipated that findings will contribute to the United Nation’s Sustainable Goal 11.2 to provide access to safe, affordable, accessible and sustainable transport systems as insights will be transferrable internationally.

Automated recognition of rear seat occupants' head position using Kinect™ 3D point cloud

INTRODUCTION Child occupant safety in motor-vehicle crashes is evaluated using Anthropomorphic Test Devices (ATD) seated in optimal positions. However, child occupants often assume suboptimal positions during real-world driving trips. Head impact to the seat back has been identified as one important injury causation scenario for seat belt restrained, head-injured children (Bohman et al., 2011). There is therefore a need to understand the interaction of children with the Child Restraint System to optimize protection. METHOD Naturalistic driving studies (NDS) will improve understanding of out-of-position (OOP) trends. To quantify OOP positions, an NDS was conducted. Families used a study vehicle for two weeks during their everyday driving trips. The positions of rear-seated child occupants, representing 22 families, were evaluated. The study vehicle - instrumented with data acquisition systems, including Microsoft Kinect™ V1 - recorded rear seat occupants in 1120 driving 26 trips. Three novel analytical methods were used to analyze data. To assess skeletal tracking accuracy, analysts recorded occurrences where Kinect™ exhibited invalid head recognition among a randomly-selected subset (81 trips). Errors included incorrect target detection (e.g., vehicle headrest) or environmental interference (e.g., sunlight). When head data was present, Kinect™ was correct 41% of the time; two other algorithms - filtering for extreme motion, and background subtraction/head-based depth detection are described in this paper and preliminary results are presented. Accuracy estimates were not possible because of their experimental nature and the difficulty to use a ground truth for this large database. This NDS tested methods to quantify the frequency and magnitude of head positions for rear-seated child occupants utilizing Kinect™ motion-tracking. RESULTS This studys results informed recent ATD sled tests that replicated observed positions (most common and most extreme), and assessed the validity of child occupant protection on these typical CRS uses. SUMMARY Optimal protection in vehicles requires an understanding of how child occupants use the rear seat space. This study explored the feasibility of using Kinect™ to log positions of rear seated child occupants. Initial analysis used the Kinect™ systems skeleton recognition and two novel analytical algorithms to log head location. PRACTICAL APPLICATIONS This research will lead to further analysis leveraging Kinect™ raw data - and other NDS data - to quantify the frequency/magnitude of OOP situations, ATD sled tests that replicate observed positions, and advances in the design and testing of child occupant protection technology.