Traffic climate and driver behaviors: The moderating role of driving skills in Turkey and China

Introduction: While road traffic accidents and fatalities are a worldwide problem, the rates of road traffic accidents and fatalities show differences among countries. Similarly, driver behaviors, traffic climate, and their relationships also show differences among countries. The aim of the current study is to investigate the moderating effect of driving skills on the relationship between traffic climate and driver behaviors by country. (Turkey and China). Method: There were 294 Turkish drivers and 292 Chinese drivers, and they completed the Traffic Climate Scale, the Driving Skills Inventory, and the Driver Behavior Questionnaire. The moderated moderation analyses were conducted with Hayes PROCESS tool on SPSS. Results: The results showed that safety skills moderated the relationship between internal requirements and violations both in Turkey and China. Safety skills also moderated the relationship between internal requirements and errors only in China and the relationship between functionality and violations in Turkey. Perceptual-motor skills moderated the relationships between external affective demands and errors, and also the relationship between internal requirements and positive driver behaviors in Turkey. It can be inferred that driving skills has different influences on traffic climate-driver behaviors relationship in different cultures and there might be cultural differences in the evaluation of drivers’ own driving skills. Practical Applications: Among driving skills, safety skills have a more critical role to increase road safety by decreasing number of violations. Interventions to increase safety skills of drivers might be promising for road safety.     

Cycle Aware Package: Using Haddon’s matrix to reduce novice driver crashes with cyclists

Abstract

Objectives: What are we teaching drivers about safely interacting with cyclists? This is the main objective of the Cycle Aware project. As part of the study, a teaching and learning package is being developed to fill this gap in Australia.

Methods: Cycle Aware is a major national project that takes a mixed methods approach to investigate how cyclists are taught to share the road with cyclists when learning to drive. The project has five stages: (1) a national review of the driver licensing documentation; (2) interviews with key stakeholders (n?=?35) involved with novice driver education; (3) analysis of cyclist-novice driver crash data to identify the most frequent crash types; (4) develop a teaching and learning package (Cycle Aware Package), and; trial and evaluate Cycle Aware Package.

Results: Overall, drivers are taught little about sharing the road with cyclists. Representation of cyclists in government documentation is mixed and mostly negative and interviews identified driver-cyclist tensions related to attitudes and awareness of sharing the road. Crash types were similar among novice and experienced drivers. The Cycle Aware Package is being finalised and will be trialled in South Australia and Northern Territory in early 2019.

Conclusions: Cycle Aware will provide new insights into the way drivers are taught to share the road with cyclists. The Cycle Aware Package with interactive online content and driver competencies will facilitate a new approach to addressing this gap among Australia drivers.     

Impact of medical fitness to drive policies in preventing property damage,injury, and death from motor vehicle collisions in Ontario,Canada

Introduction: Drivers with medical conditions and functional impairments are at increased collision risk. A challenge lies in identifying the point at which such risk becomes unacceptable to society and requires mitigating measures. This study models the road safety impact of medical fitness-to-drive policy in Ontario. Method: Using data from 2005 to 2014, we estimated the losses to road safety incurred during the time medically-at-risk drivers were under review, as well as the savings to road safety accrued as a result of licensing decisions made after the review process. Results: While under review, drivers with medical conditions had an age- and sex-standardized collision rate no different from the general driver population, suggesting no road safety losses occurred (RR = 1.02; 95% CI: 0.93–1.12). Licensing decisions were estimated to have subsequently prevented 1,211 (95% CI: 780–1,730) collisions, indicating net road safety savings resulting from medical fitness to drive policies. However, more collisions occurred than were prevented for drivers with musculoskeletal disorders, sleep apnea, and diabetes. We theorize on these findings and discuss its multiple implications. Conclusions: Minimizing the impact of medical conditions on collision occurrence requires robust policies that balance fairness and safety. It is dependent on efforts by academic researchers (who study fitness to drive); policymakers (who set driver medical standards); licensing authorities (who make licensing decisions under such standards); and clinicians (who counsel patients on their driving risk and liaise with licensing authorities). Practical Applications: Further efforts are needed to improve understanding of the effects of medical conditions on collision risk, especially for the identified conditions and combinations of conditions. Results reinforce the value of optimizing the processes by which information is solicited from physicians in order to better assess the functional impact of drivers’ medical conditions on driving and to take suitable licensing action.     

Gender differences of young drivers on injury severity outcome of highway crashes

ProblemGender differences of young drivers involved in crashes and the associated differences in risk factors have not been fully explored in the United States (U.S.). Accordingly, this study investigated the topic, where the odds ratios (ORs) were used to identify differences in crash involvements between male and female young drivers.MethodLogistic regression models for injury severity of young male drivers and young female drivers were developed. Different driver, environmental, vehicle, and road related factors that have affected young female drivers' and young male drivers' crash involvements were identified using the models.ResultsResults indicated that some variables are significantly related to female drivers' injury risk but not male drivers' injury risk and vice versa. Variables such as driving with valid licenses, driving on weekends, avoidance or slow maneuvers at time of crash, non-collision and overturn crashes, and collision with a pedestrian were significant variables in female driver injury severity model but not in young male driver severity model. Travel on graded roadways, concrete surfaces, and wet road surfaces, collision with another vehicle, and rear-end collisions were variables that were significant in male-driver severity model but not in female-driver severity model.SummaryFactors which increase young female drivers' injury severity and young male drivers' injury severity were identified. This study adds detailed information about gender differences and similarities in injury severity risk of young drivers.Practical applicationsIt is important to note that the findings of this study show that gender differences do exists among young drivers. This sends a message to the industry that the transportation professionals and researchers, who are developing countermeasures to increase the traffic safety, may need to pay attention to the differences. This might be particularly true when developing education materials for driver training for young/inexperienced drivers.     

Driving safety improves after individualized training: An RCT involving older drivers in an urban area

Objective: This study aimed to reproduce the results of a previous investigation on the safety benefits of individualized training for older drivers. We modified our method to address validity and generalizability issues.

Methods: Older drivers were randomly assigned to one of the 3 arms: (1) education alone, (2) education?+?on road training, and (3) education?+?on road?+?simulator training. Older drivers were recruited from a larger urban community. At the pre- and posttests (separated by 4 to 8 weeks) participants followed driving directions using a Global Positioning System (GPS) navigation system.

Results: Our findings support the positive influence of individualized on-road training for urban-dwelling older drivers. Overall, driving safety improved among drivers who received on-road training over those who were only exposed to an education session, F(1, 40) = 11.66, P = .001 (26% reduction in total unsafe driving actions [UDAs]). Statistically significant improvements were observed on observation UDAs (e.g., scanning at intersections, etc.), compliance UDAs (e.g., incomplete stop), and procedural UDAs (e.g., position in lane).

Conclusion: This study adds to the growing evidence base in support of individualized older driver training to optimize older drivers’ safety and promote continued safe driving.     

Prevalence and characteristics of road traffic injuries among young drivers in Oman, 2009–2011

Objectives: Studies from different parts of the world have indicated that the impact of road traffic incidents disproportionally affects young adults. Few known studies have been forthcoming from Arabian Gulf countries. Within Oman, a high proportion of the population is under the age of 20. Coupled with the drastic increase in motorization in recent years, there is a need to understand the state of road safety among young people in Oman. The current research aimed to explore the prevalence and characteristics of road traffic injuries among young drivers aged 17–25 years.

Methods: Crash data from 2009 to 2011 were extracted from the Directorate General of Traffic, Royal Oman Police (ROP) database in Oman. The data were analyzed to explore the impact of road crashes on young people (17–25 years), the characteristics of young driver crashes, and how these differ from older drivers and to identify key predictors of fatalities in young driver crashes.

Results: Overall, young people were overrepresented in injuries and fatalities within the sample time period. Though it is true that many young people in crashes were driving at the time, it was also evident that young people were often victims in a crash caused by someone else. Thus, to reduce the impact of road crashes on young people, there is a need to generally address road safety within Oman. When young drivers were involved in crashes they were predominantly male. The types of crashes these drivers have can be broadly attributed to risk taking and inexperience. Speeding and nighttime driving were the key risk factors for fatalities.

Conclusion: The results highlight the need to address young driver safety in Oman. From these findings, the introduction of a graduated driver licensing system with nighttime driving restrictions could significantly improve young driver safety.     

Older driver training programs: A systematic review of evidence aimed at improving behind-the-wheel performance

IntroductionAge- and health-related changes, alongside declines in driving confidence and on-road exposure, have been implicated in crashes involving older drivers. Interventions aimed at improving behind-the-wheel behavior are diverse and their associated impact remains unclear. This systematic review examined evidence on older driver training with respect to (1) road safety knowledge; (2) self-perceived changes in driving abilities; and (3) behind-the-wheel performance. Method Nine databases were searched for English-language articles describing randomized controlled trials (RCTs) and non-RCTs of driver training interventions aimed at those aged 55+ who did not have medical or other impairments that precluded licensure. Quality appraisals were conducted using Cochrane’s Risk of Bias Tool (RoB) and Risk Of Bias In Non-randomized Studies – of Interventions tool (ROBINS – I). [PROSPERO; registration no. CRD42018087366]. Results Twenty-five RCTs and eight non-RCTs met the inclusion criteria. Interventions varied in their design and delivery where classroom-based education, or a combination of classroom-based education with on-road feedback, improved road safety knowledge. Training tailored to individual participants was found to improve self-perceived and behind-the-wheel outcomes, including crashes. Conclusions Interventions comprised of tailored training can improve knowledge of road safety, changes to self-perception of driving abilities, and improved behind-the-wheel performance of older drivers. Future research should compare modes of training delivery for this driver population to determine the optimal combinations of off- and/or on-road training. Practical applications Training programs aimed at older drivers should be supported by theory and research evidence. By conducting comparative trials with a sufficient sample size alongside well-defined outcomes that are designed in accordance with reporting guidelines, the most effective approaches for training older drivers will be identified.     

Driver behavior analysis for right-turn drivers at signalized intersections using SHRP 2 naturalistic driving study data

IntroductionUnderstanding driver behavior is important for traffic safety and operation, especially at intersections where different traffic movements conflict. While most driver-behavior studies are based on simulation, this paper documents the analysis of driver-behavior at signalized intersections with the SHRP 2 Naturalistic Driving Study (NDS) data. This study analyzes the different influencing factors on the operation (speed control) and observation of right-turn drivers.MethodA total of 300 NDS trips at six signalized intersections were used, including the NDS time-series sensor data, the forward videos and driver face videos. Different factors of drivers, vehicles, roads and environments were studied for their influence on driver behavior. An influencing index function was developed and the index was calculated for each influencing factor to quantitatively describe its influencing level. The influencing index was applied to prioritize the factors, which facilitates development and selection of safety countermeasures to improve intersection safety. Drivers' speed control was analyzed under different conditions with consideration of the prioritized influencing factors.ResultsVehicle type, traffic signal status, conflicting traffic, conflicting pedestrian and driver age group were identified as the five major influencing factors on driver observation.ConclusionsThis research revealed that drivers have high acceleration and low observation frequency under Right-Turn-On-Red (RTOR), which constituted potential danger for other roadway users, especially for pedestrians.Practical applicationsAs speed has a direct influence on crash rates and severities, the revealed speed patterns of the different situations also benefit selection of safety countermeasures at signalized intersections.     

An Analysis of Young Driver Crash Types and the Associated Lifetime Care Cost in Victoria,Australia

Objective: The elevated crash involvement rate of young drivers is well documented. Given the higher crash risk of young drivers and the need for innovative policy and programs, it remains important to fully understand the type of crashes young drivers are involved in, and knowledge of the lifetime care cost of crashes can support effective policy development. The aim of this article is to document the number and type of young driver crashes, as well as the associated lifetime care cost over a 9-year period (2005–2013) in Victoria, Australia.

Methods: In Victoria, Australia, the Transport Accident Commission (TAC) has legislated responsibility for road safety and the care of persons injured in road crashes, irrespective of fault. TAC claims data for the period 2005–2013 were used to document the number and type of young driver crashes. Lifetime care costs (past and future payment liabilities) were calculated by Taylor Fry actuarial consultancy. License and population data were used to define the crash involvement rate of young drivers.

Results: Over the 9-year period, 16,817 claims were lodged to the TAC by drivers 18–25 years of age following a crash. There were 646 fewer drivers aged 18–25 killed and injured in 2013, compared to 2005, representing an unadjusted change of ?28.7% (?29.8% males; ?28.4% females). The total lifetime care cost of young drivers killed and injured in Victoria for the period 2005–2013 was estimated to be AU$634 million (US$493 million). Differences between males and females, single- and multivehicle crashes, and fatalities and injuries were found to be statistically significant. Run-off-road crashes and crashes from opposing direction were overrepresented in the lifetime care costs for young driver claimants. Twenty-eight injured drivers were classified as high-severity claims. These 28 claimants require additional long-term care, which was estimated to be AU$219 million; of these 28, 24 were male (85.7%). The long-term care costs for these 28 drivers (0.16%) accounts for 34.5% of the total lifetime care cost of all 18- to 25-year-old injured drivers.

Conclusions: By using no-fault lifetime care costs that account for medical and like expenses, rehabilitation, and social reintegration costs, a more accurate understanding of the cost of young driver crashes can be determined. Application of these costs to specific crash types highlights new priorities and opportunities for developing programs to reduce young driver crashes.     

Medical review process and license disposition of drivers referred by law enforcement in Virginia

IntroductionMedically at-risk drivers come to the attention of licensing authorities through referrals from a variety of sources, including: physicians, family members, court systems, and law enforcement. A recently sponsored project by the National Highway Traffic Safety Administration examined a training intervention for law enforcement to increase their awareness of medical conditions and medications that impair driving and the procedures for reporting these drivers in Virginia.MethodA component of this project included an evaluation of the medical review process and licensing outcomes for 100 drivers randomly selected from a pool of over 1,000 drivers referred from law enforcement officers to the Virginia Department of Motor Vehicles over a 6-month period in 2007 and 2008 prior to any training program intervention.ResultsKey findings from the evaluation of 100 drivers referred for medical review by law enforcement were as follows. Over two-thirds of the drivers came to the attention of the referring officer because they were involved in a crash. The most prevalent indications of a medical condition or functional impairment provided by law enforcement for these referrals were: loss of consciousness, blackout, or seizures (28%); disorientation, confusion, and mental disability (16%); and physical impairments (8%). Eighty-eight percent of the drivers received some type of licensing action (e.g., restriction, suspension, or periodic review). Only 12% of the referred drivers did not require any licensing action.ConclusionsLaw enforcement provides a vital role in the identification and referral of medically impaired drivers to licensing authorities for reexamination. Training programs can inform law enforcement officers of the signs of medical impairment (both on-road behavior, and physical and psychological clues once a driver has been pulled over), and procedures for reporting their observations and concern for safety to licensing authorities.Impact on IndustryReexamination of drivers with functional and medical impairments and any consequent restrictions and/or periodic reporting requirements can improve the safety and mobility of these drivers, and the motoring public as well.     

The sex disparity in risky driving: A survey of Colombian young drivers

Objective: The overrepresentation of young drivers in poor road safety outcomes has long been recognized as a global road safety issue. In addition, the overrepresentation of males in crash statistics has been recognized as a pervasive young driver problem. Though progress in road safety evidenced as a stabilization and/or reduction in poor road safety outcomes has been made in developed nations, less-developed nations contribute the greatest road safety trauma, and developing nations such as Colombia continue to experience increasing trends in fatality rates. The aim of the research was to explore sex differences in self-reported risky driving behaviors of young drivers, including the associations with crash involvement, in a sample of young drivers attending university in Colombia.

Methods: The Spanish version of the Behaviour of Young Novice Drivers Scale (BYNDS-Sp) was applied in an online survey to a sample of 392 students (225 males) aged 16–24 years attending a major university. Appropriate comparative statistics and logistic regression modeling were used when analyzing the data.

Results: Males reported consistently more risky driving behaviors, with approximately one quarter of all participants reporting risky driving exposure. Males reported greater crash involvement, with violations such as speeding associated with crash involvement for both males and females.

Conclusion: Young drivers in Colombia appear to engage in the same risky driving behaviors as young drivers in developed nations. In addition, young male drivers in Colombia reported greater engagement in risky driving behaviors than young female drivers, a finding consistent with the behaviors of young male drivers in developed nations. As such, the research findings suggest that general interventions such as education, engineering, and enforcement should target transient rule violations such as speeding and using a handheld mobile phone while driving for young drivers in Colombia. Future research should investigate how these interventions could be tailored specifically for the Colombian cultural context, including how their effects can be evaluated, prior to implementation.     

A new approach to managing work-related road traffic injury: The development of a health investment framework

Objective: Statistics indicate that employees commuting or traveling as part of their work are overrepresented in workplace injury and death. Despite this, many organizations are unaware of the factors within their organizations that are likely to influence potential reductions in work-related road traffic injury.

Methods: This article presents a multilevel conceptual framework that identifies health investment as the central feature in reducing work-related road traffic injury. Within this framework, we explore factors operating at the individual driver, workgroup supervisor, and organizational senior management levels that create a mutually reinforcing system of safety.

Results: The health investment framework identifies key factors at the senior manager, supervisor, and driver levels to cultivating a safe working environment. These factors are high-performance workplace systems, leader–member exchange and autonomy, trust and empowerment, respectively. The framework demonstrates the important interactions between these factors and how they create a self-sustaining organizational safety system.

Conclusions: The framework aims to provide insight into the future development of interventions that are strategically aligned with the organization and target elements that facilitate and enhance driver safety and ultimately reduce work-related road traffic injury and death.     

Assessing the safety criticality of driver behavior toward cyclists at intersections

Abstract

Objective: Detailed analyses of car-to-cyclist accidents show that drivers intending to turn right at T-junctions collide more often with cyclists crossing from the right side on the bicycle lane than drivers intending to turn left. This fact has led to numerous studies examining the behavior of drivers turning left and right. However, the most essential question still has not been sufficiently answered: is the behavior of drivers intending to turn right generally more safety critical than the behavior of those intending to turn left? The purpose of this article is to provide a method that allows to determine whether a driver’s behavior toward cyclists can retrospectively be assessed as critical or non-critical.

Methods: Several theoretical considerations enriched by findings of experimental studies were employed to devise a multi-measure method. This method was applied to a dataset containing real-world approaching behavior of 48 drivers turning right and left at four T-junctions with different sight obstructions. For each driver a behavior-specific criticality was defined based on both, their driving and gaze behavior. Moreover, based on the behavior-specific criticality of each driver, the required field of view to see a cyclist from the right was defined and was set into relation with the available field of view of the T-junction.

Results: The results show that only a small portion of the drivers within the dataset would have posed an actual risk to cyclists crossing from the right side. Those situations with a higher safety criticality did not only arise when drivers intended to turn right, but also left.

Conclusion: Therefore, the analysis can only provide an explanation for the higher proportion of accidents between drivers turning right and cyclists crossing from the right side in certain situations. Further research, for example analyses of exposure data regarding the frequency of turning manoeuvers at T-junctions, is needed in order to explain the higher proportion of accidents between drivers turning right and cyclists crossing from the right side.     

Taxi driver speeding: Who,when, where and how? A comparative study between Shanghai and New York City

Objective: The 3 objectives of this study are to (1) identify the driving style characteristics of taxi drivers in Shanghai and New York City (NYC) using taxi Global Positioning System (GPS) data and make a comparative analysis; (2) explore the influence of different driving style characteristics on the frequency of speeding (who and how?) and (3) explore the influence of driving style characteristics, road attributes, and environmental factors on the speeding rate (when, where, and how?)

Methods: This study proposes a driver–road–environment identification (DREI) method to investigate the determinant factors of taxi speeding violations. Driving style characteristics, together with road and environment variables, were obtained based on the GPS data and auxiliary spatiotemporal data in Shanghai and NYC.

Results: The daily working hours of taxi drivers in Shanghai (18.6 h) was far more than in NYC (8.5 h). The average occupancy speed of taxi drivers in Shanghai (21.3 km/h) was similar to that of NYC (20.3 km/h). Speeders in both cities had shorter working hours and longer daily driving distance than other taxi drivers, though their daily income was similar. Speeding drivers routinely took long-distance trips (>10 km) and preferred relatively faster routes. Length of segments (1.0–1.5 km) and good traffic condition were associated with high speeding rates, whereas central business district area and secondary road were associated with low speeding rates. Moreover, many speeding violations were identified between 4:00 a.m. and 7:00 a.m. in both Shanghai and NYC and the worst period was between 5:00 a.m. and 6:00 a.m. in both cities.

Conclusions: Characteristics of drivers, road attributes, and environment variables should be considered together when studying driver speeding behavior. Findings of this study may assist in stipulating relevant laws and regulations such as stricter offense monitoring in the early morning, long segment supervision, shift rule regulation, and working hour restriction to mitigate the risk of potential crashes.     

A novel driver hazard perception sensitivity model based on drivers’ characteristics: A simulator study

Objective: Considering the high annual number of fatal driving accidents in Iran, any approach for reducing the number or severity of driving accidents is a positive step toward decreasing accident-related losses. Accidents can often be avoided by a timely reaction of the driver. One of the steps before reacting to a hazard is perception. Some driver characteristics may affect road hazard perception. In this research, it was assumed that various driver characteristics, including demographic characteristics and cognitive characteristics, have an impact on driver perception.

Methods: The driving simulator used in this research provides various scenarios; for example, passing a pedestrian or animal across the road or placing fixed objects in a 2-lane separated rural road for 2 groups of experienced and inexperienced drivers under day and night lighting conditions. The go/no-go test was carried out in order to assess drivers’ attention to driving tasks and inhibitory control. A structural equation model (SEM) was used to estimate the relation between driver characteristics and sensitivity to road hazard perception. A new hazard perception index was proposed based on the time intervals in the hazard vulnerability.

Results: The results show that the most effective variables in the analysis of sensitivity to hazard perception are driving experience (in kilometers) during the last 3 years and road lighting conditions. Moreover, hazard perception sensitivity was improved by better inhibitory control, selective attention, and decision making, more carefulness, the average amount of daily sleep, and marital status.

Conclusion: The results of this research may be useful in educating and advertising programs. It also could enhance sensitivity to perception of hazards such as pedestrians, animals, and fixed obstacles among young and novice drivers.     

Assessing drivers' response during automated driver support system failures with non-driving tasks

IntroductionWith the increase in automated driver support systems, drivers are shifting from operating their vehicles to supervising their automation. As a result, it is important to understand how drivers interact with these automated systems and evaluate their effect on driver responses to safety critical events. This study aimed to identify how drivers responded when experiencing a safety critical event in automated vehicles while also engaged in non-driving tasks.MethodIn total 48 participants were included in this driving simulator study with two levels of automated driving: (a) driving with no automation and (b) driving with adaptive cruise control (ACC) and lane keeping (LK) systems engaged; and also two levels of a non-driving task (a) watching a movie or (b) no non-driving task. In addition to driving performance measures, non-driving task performance and the mean glance duration for the non-driving task were compared between the two levels of automated driving.ResultsDrivers using the automated systems responded worse than those manually driving in terms of reaction time, lane departure duration, and maximum steering wheel angle to an induced lane departure event. These results also found that non-driving tasks further impaired driver responses to a safety critical event in the automated system condition.ConclusionIn the automated driving condition, driver responses to the safety critical events were slower, especially when engaged in a non-driving task.Practical applicationTraditional driver performance variables may not necessarily effectively and accurately evaluate driver responses to events when supervising autonomous vehicle systems. Thus, it is important to develop and use appropriate variables to quantify drivers' performance under these conditions.     

Driving while impaired by alcohol: An analysis of drink-drivers involved in UK collisions

Objective: Drink-driving represents a critical issue on international organizations’ agendas as one of the key behavioral risk factors in road traffic safety, alongside speed and nonuse of motorcycle helmets, seat belts, and child restraints. Changing road user behaviors regarding these 5 factors is a critical component in reducing road traffic injuries and casualties. The objective of this study is the identification of drivers who are more likely to contribute to crashes in the UK while impaired by alcohol to design targeted drink drive compliance campaigns.

Method: To profile drivers with the factor “impaired by alcohol” assigned in collisions, an extensive data set is used, including all reported injury collisions between 2011 and 2015 in the UK (police records), merged with the Experian Mosaic Database. A multilevel mixed-effects logistic regression is conducted, utilizing the hierarchical nature of the data (drivers within Mosaic types).

Results: Using multilevel mixed-effects logistic regression analysis, the finding is that some driver profiles are more likely to contribute to crashes and are assigned the contributory factor “impaired by alcohol.” Drink-related crashes are more common in some circumstances or for some crash-involved driver groups than others. For instance, alcohol-related crashes are more likely to occur on single carriageways and among males and 25- to 35-year-olds. Drink-drive-related crashes are found to be strongly associated with dark lighting conditions and, more specifically, with late night hours (the interval between 3:00 a.m. and 4:00 a.m. accounts for a third of the drink-drive-related collisions). Using the Experian Mosaic Database which divides the UK population into 66 types based on demographic, lifestyle, and behavior characteristics, the finding is that, among crash-involved drivers, some Mosaic types are significantly more likely (e.g., pocket pensions, dependent greys, streetwise singles) and others are significantly less likely (e.g., crowded kaleidoscope, cultural comfort, penthouse chic) to contribute to a drink-related crash.

Conclusions: The outcome is a more nuanced understanding of drivers contributing to drink-related crashes in the UK. The study concludes by discussing the implications for governments and other interested bodies for better targeting and delivery of public education campaigns and interventions.     

The effects of drug and alcohol consumption on driver injury severities in single-vehicle crashes

Objective: It is well known that alcohol and drugs influence driving behavior by affecting the central nervous system, awareness, vision, and perception/reaction times, but the resulting effect on driver injuries in car crashes is not fully understood. The purpose of this study was to identify factors affecting the injury severities of unimpaired, alcohol-impaired, and drug-impaired drivers.

Method: The current article applies a random parameters logit model to study the differences in injury severities among unimpaired, alcohol-impaired, and drug-impaired drivers. Using data from single-vehicle crashes in Cook County, Illinois, over a 9-year period from January 1, 2004, to December 31, 2012, separate models for unimpaired, alcohol-impaired, and drug-impaired drivers were estimated. A wide range of variables potentially affecting driver injury severity was considered, including roadway and environmental conditions, driver attributes, time and location of the crash, and crash-specific factors.

Results: The estimation results show significant differences in the determinants of driver injury severities across groups of unimpaired, alcohol-impaired, and drug-impaired drivers. The findings also show that unimpaired drivers are understandably more responsive to variations in lighting, adverse weather, and road conditions, but these drivers also tend to have much more heterogeneity in their behavioral responses to these conditions, relative to impaired drivers. In addition, age and gender were found to be important determinants of injury severity, but the effects varied significantly across all drivers, particularly among alcohol-impaired drivers.

Conclusions: The model estimation results show that statistically significant differences exist in driver injury severities among the unimpaired, alcohol-impaired, and drug-impaired driver groups considered. Specifically, we find that unimpaired drivers tend to have more heterogeneity in their injury outcomes in the presence potentially adverse weather and road surface conditions. This makes sense because one would expect unimpaired drivers to apply their full knowledge/judgment range to deal with these conditions, and the variability of this range across the driver population (with different driving experiences, etc.) should be great. In contrast, we find, for the most part, that alcohol-impaired and drug-impaired drivers have far less heterogeneity in the factors that affect injury severity, suggesting an equalizing effect resulting from the decision-impairing substance.     

Assessing characteristics related to the use of seatbelts and cell phones by drivers: Application of a bivariate probit model

IntroductionThe effects of cell phone use and safety belt use have been an important focus of research related to driver safety. Cell phone use has been shown to be a significant source of driver distraction contributing to substantial degradations in driver performance, while safety belts have been demonstrated to play a vital role in mitigating injuries to crash-involved occupants.MethodThis study examines the prevalence of cell phone use and safety belt non-use among the driving population through direct observation surveys. A bivariate probit model is developed to simultaneously examine the factors that affect cell phone and safety belt use among motor vehicle drivers.ResultsThe results show that several factors may influence drivers' decision to use cell phones and safety belts, and that these decisions are correlated.Practical applicationsUnderstanding the factors that affect both cell phone use and safety belt non-use is essential to targeting policy and programs that reduce such behavior.     

Modelling the relationship of driver license and offense history with fatal and serious injury (FSI) crash involvement

Introduction: Previous research has indicated that increases in traffic offenses are linked to increased crash involvement rates, making reductions in offending an appropriate measure for evaluating road safety interventions in the short-term. However, the extent to which traffic offending predicts fatal and serious injury (FSI) crash involvement risk is not well established, prompting this new Victorian (Australia) study. Method: A preliminary cluster analysis was performed to describe the offense data and assess FSI crash involvement risk for each cluster. While controlling demographic and licensing variables, the key traffic offenses that predict future FSI crash involvement were then identified. The large sample size allowed the use of machine learning methods such as random forests, gradient boosting, and Least Absolute Shrinkage and Selection Operator (LASSO) regression. This was done for the ‘all driver’ sample and five sometimes overlapping groups of drivers; the young, the elderly, and those with a motorcycle license, a heavy vehicle license endorsement and/or a history of license bans. Results: With the exception of the group of drivers who had a history of bans, offense history significantly improved the accuracy of models predicting future FSI crash involvement using demographic and licensing data, suggesting that traffic offenses may be an important factor to consider when analyzing FSI crash involvement risk and the effects of road safety countermeasures. Conclusions: The results are helpful for identifying driver groups to target with further road safety countermeasures, and for showing that machine learning methods have an important role to play in research of this nature. Practical Application: This research indicates with whom road safety interventions should particularly be applied. Changes to driver demerit policies to better target offenses related to FSI crash involvement and repeat traffic offenders, who are at greater risk of FSI crash involvement, are recommended.