Does gender moderate the relationship between driver aggression and its risk factors?

Aim

The current study assessed gender as a potential moderator of the relationship between self-reported driver aggression and various demographic variables, general and driving-related risk factors.

Methods

Using data from a general-population telephone survey conducted from July 2002 through June 2005, two approaches to binary logistic regression were adopted. Based on the full dataset (n = 6259), the initial analysis was a hierarchical-entry regression examining self-reported driver aggression in the last 12 months. All demographic variables (i.e., gender, age, income, education, marital status), general risk factors (i.e., psychological distress, binge drinking, cannabis use), and driving-related risk factors (i.e., driving exposure, stressful driving, exposure to busy roads, driving after drinking, driving after cannabis use) were entered in the first block, and all two-way interactions with gender were entered stepwise in the second block. The subsequent analysis involved dividing the sample by gender and conducting logistic regressions with main effects only for males (n = 2921) and females (n = 3338) separately.

Results

Although the prevalence of driver aggression in the current sample was slightly higher among males (38.5%) than females (32.9%), the difference was small, and gender did not enter as a significant predictor of driver aggression in the overall logistic regression. In that analysis, difficulty with social functioning and being older were associated with a reduced risk of driver aggression. Marital status and education were unrelated to aggression, and all other variables were associated with an increased risk of aggression. Gender was found to moderate the relationships between driver aggression and only three variables: income, psychological distress, and driving exposure. Separate analyses on the male and female sub-samples also found differences in the predictive value of income and driving exposure; however, the difference for psychological distress could not be detected using this separate regression approach. The secondary analysis also identified slight differences in the predictive value of four of the risk factors, where the odds ratios for both males and females were in the same direction but only one of the two was statistically significant.

Conclusions

The results demonstrate the importance of conducting the gender analysis using both regression approaches. With few exceptions, factors that were predictive of driver aggression were generally the same for both male and female drivers.     

Can we improve clinical prediction of at-risk older drivers?

Objectives

To conduct a pilot study to evaluate the predictive value of the Montreal Cognitive Assessment test (MoCA) and a brief test of multiple object tracking (MOT) relative to other tests of cognition and attention in identifying at-risk older drivers, and to determine which combination of tests provided the best overall prediction.

Methods

Forty-seven currently licensed drivers (58–95 years), primarily from a clinical driving evaluation program, participated. Their performance was measured on: (1) a screening test battery, comprising MoCA, MOT, Mini-Mental State Examination (MMSE), Trail-Making Test, visual acuity, contrast sensitivity, and Useful Field of View (UFOV) and (2) a standardized road test.

Results

Eighteen participants were rated at-risk on the road test. UFOV subtest 2 was the best single predictor with an area under the curve (AUC) of .84. Neither MoCA nor MOT was a better predictor of the at-risk outcome than either MMSE or UFOV, respectively. The best four-test combination (MMSE, UFOV subtest 2, visual acuity and contrast sensitivity) was able to identify at-risk drivers with 95% specificity and 80% sensitivity (.91 AUC).

Conclusions

Although the best four-test combination was much better than a single test in identifying at-risk drivers, there is still much work to do in this field to establish test batteries that have both high sensitivity and specificity.     

A longitudinal investigation of the predictors of older drivers’ speeding behaviour

There is little objective evidence about the extent older drivers’ are involved in speeding or factors that may influence this behaviour. Particular concern exists for the increasing number of older drivers with poor or declining cognitive and visual function. This study investigates whether a reduction in speeding forms part of the self-restrictive driving behaviour evident when older drivers experience poor cognitive and visual function. Driving data over 12 months were collected from 182 volunteers aged 75–94 years. Driving speed was estimated using Global Positioning System location, and speed limit data was based on a service-provider database. Speed events were defined as driving 1 km/h or more, with 3% tolerance, above a single speed limit, averaged over 30 s. Almost all participants (99%) were involved in speed events. While, 16–31% of participants experienced a meaningful decline in cognitive or visual function during the 12-months, these declines were not predictive of a change in speed events. Our results indicate speeding behaviour in this age group was highly prevalent, but less so for the oldest drivers whereby the rate of speed events was 7% lower per year older (IRR = 0.93, 95%CI = 0.89–0.96). Older drivers with worse function were less involved in speed events (unadjusted for distance driven) during 12 months of observation. Weekly distance driven decreased over the year by approximately 0.45 km with every week of monitoring for these older drivers. When distance driven was taken into account, decreased function was not predictive of involvement in speed events, indicating the reduction in speed events may be achieved by older drivers with lower function reducing distance driven. These results are important for developing policy to address speeding behaviour of the growing population of older drivers to reduce the incidence of crashes and resulting casualties.     

Measurement of driver calibration and the impact of feedback on drivers’ estimates of performance

Recent studies focused on driver calibration show that drivers are often miscalibrated, either over confident or under confident, and the magnitude of this miscalibration changes under different conditions. Previous work has demonstrated behavioral and performance benefits of feedback, yet these studies have not explicitly examined the issue of calibration. The objective of this study was to examine driver calibration, i.e., the degree to which drivers are accurately aware of their performance, and determine whether feedback alters driver calibration. Twenty-four drivers completed a series of driving tasks (pace clocks, traffic light, speed maintenance, and traffic cones) on a test track. Drivers drove three different blocks around the test track: (1) baseline block, where no participants received feedback; (2) feedback block, where half of the participants received performance feedback while the other half received no feedback; (3) a no feedback block, where no participants received feedback. Results indicated that across two different calibration measures, drivers were sufficiently calibrated to the pace clocks, traffic light, and traffic cone tasks. Drivers were not accurately aware of their performance regarding speed maintenance, though receiving feedback on this task improved calibration. Proper and accurate measurements of driver calibration are needed before designing performance feedback to improve calibration as these feedback systems may not always yield the intended results.     

Novice drivers’ individual trajectories of driver behavior over the first three years of driving

Identifying the changes in driving behavior that underlie the decrease in crash risk over the first few months of driving is key to efforts to reduce injury and fatality risk in novice drivers. This study represented a secondary data analysis of 1148 drivers who participated in the UK Cohort II study. The Driver Behavior Questionnaire was completed at 6 months and 1, 2 and 3 years after licensure. Linear latent growth models indicated significant increases across development in all four dimensions of aberrant driving behavior under scrutiny: aggressive violations, ordinary violations, errors and slips. Unconditional and conditional latent growth class analyses showed that the observed heterogeneity in individual trajectories was explained by the presence of multiple homogeneous groups of drivers, each exhibiting specific trajectories of aberrant driver behavior. Initial levels of aberrant driver behavior were important in identifying sub-groups of drivers. All classes showed positive slopes; there was no evidence of a group of drivers whose aberrant behavior decreased over time that might explain the decrease in crash involvement observed over this period. Male gender and younger age predicted membership of trajectories with higher levels of aberrant behavior. These findings highlight the importance of early intervention for improving road safety. We discuss the implications of our findings for understanding the behavioral underpinnings of the decrease in crash involvement observed in the early months of driving.     

What can the drivers’ own description from combined sources provide in an analysis of driver distraction and low vigilance in accident situations?

Accident data play an important role in vehicle safety development. Accident data sources are generally limited in terms of how much information is provided on driver states and behaviour prior to an accident. However, the precise limitations vary between databases, due to differences in analysis focus and data collection procedures between organisations. If information about a specific accident can be retrieved from more than one data source it should be possible to combine the available information sets to facilitate data from one source to compensate for limitations in the other(s). To investigate the viability of such compensation, this study identified a set of accidents recorded in two different data sources. The first data source investigated was an accident mail survey and the second data source insurance claims documents consisting predominantly of insurance claims completed by the involved road users. An analysis of survey variables was compared to a case analysis including word data derived from the same survey and filed insurance claims documents. For each accident, the added value of having access to more than one source of information was assessed. To limit the scope of this study, three particular topics were investigated: available information on low vigilance (e.g., being drowsy, ill); secondary task distraction (e.g., talking with passengers, mobile phone use); and distraction related to the driving task (e.g., looking for approaching vehicles). Results suggest that for low vigilance and secondary task distraction, a combination of the mail survey and insurance claims documents provide more reliable and detailed pre-crash information than survey variables alone. However, driving related distraction appears to be more difficult to capture. In order to gain a better understanding of the above issues and how frequently they occur in accidents, the data sources and analysis methods suggested here may be combined with other investigation methods such as in-depth accident investigations and pre-crash data recordings.     

What does the driver look at? The influence of intersection characteristics on attention allocation and driving behavior

One of the main contributing factors with intersection accidents is lack of information due to attention allocation. In many cases, drivers fail to yield right of way to other traffic participants. One reason is that drivers have inappropriate expectations about a traffic situation. They allocate their attention primarily to certain areas of the intersection but neglect others. In a driving simulator study, the influence of intersection complexity on drivers’ expectations and their driving behavior was examined. In two T-intersections, the complexity was varied by the traffic density (low and high) using either one or two important objects: vehicles (left) with or without pedestrians (right). Additionally, the reaction to two critical incidents in close proximity of the intersections was examined. Gaze behavior, vehicle reactions, and subjective data were recorded. 40 subjects (26 male, 14 female, M = 31.0 years, SD = 11.9 years) participated in the study. Interestingly, the least complex intersections showed the most accidents which was interpreted as the result of inadequate attention allocation. It was shown that both the drivers’ attention allocation and vehicle velocity when turning off were responsible for this effect. The results contribute to a better understanding of the role of drivers’ expectation and attention allocation in the causation of intersection accidents.     

Are rural older drivers subject to low-mileage bias?

Comparing exposure-based collision statistics between older drivers based on age alone erroneously assumes a linear relationship between exposure and collision frequency. Research has suggested that low-mileage drivers, of any age, tend to have higher exposure-based collision rates because the majority of their travel is typically on congested city streets with higher potential for collisions, referred to as “low-mileage bias”. It is unclear whether it is appropriate to extend this perspective to rural older drivers, where it could be expected they would likely have very different travel habits than an urban older driver with equivalent annual mileage. Consequently, reliance on “low-mileage-bias” as an explanation for high collision rates among seniors would benefit from the distinction of the differences in the type of driving exposure between urban and rural drivers.This paper used the detailed driving exposure information obtained from a Global Positioning System (GPS) supported travel diary study to explore whether “low-mileage bias” exists for rural older drivers. Revealed behaviour from GPS travel diaries of a convenience sample of 60 rural drivers aged 54–92 years showed the proportion of travel on urban streets increased with self-reported mileage and decreased with age. This finding is contrary to previous results where no distinction was made between urban and rural drivers. These results, combined with previous research showing the oldest rural drivers (81 years and older) have higher collision rates than their urban counterparts, suggests “low-mileage bias” may not exist in the rural context. It is possible the collision risk for the oldest rural drivers is understated, but further research is required. Self-reported mileage groups are a useful way to organize and analyze exposure and collision information, but age group analysis should not be excluded.     

Where are we on driver distraction? Methods,approaches and recommendations

Research within the road transport domain is progressively recognising the importance of taking a systems view of accident analysis. This signals a movement away from the more traditional approaches that aim to determine cause–effect relationships and attribute blame to the end-user. The multiple accidents associated with distracted driving have typically sought to establish the role of the driver and attribute responsibility to the individual. This paper will look at the approach that has been used to study distracted driving, the methods employed to study it and the recommendations they have provided to practise. The role of rapidly developing technology is discussed as more sources of distraction are presented to the driver. The limitations of the current approach lead to the proposition of a systems approach to driver distraction that aligns with the study of safety in other domains. This paper provides a novel overview of the variety of methodologies used to study distracted driving and how they may impact on the resulting countermeasures. The suggestion of a research–practice gap within the road transport domain is explored. The benefits of systems-based approaches, and their place in advancing driver distraction research for the development of future recommendations, are presented.     

Intersection assistance: A safe solution for older drivers?

Within the next few decades, the number of older drivers operating a vehicle will increase rapidly (Eurostat, 2011). As age increases so does physical vulnerability, age-related impairments, and the risk of being involved in a fatal crashes. Older drivers experience problems in driving situations that require divided attention and decision making under time pressure as reflected by their overrepresentation in at-fault crashes on intersections. Advanced Driver Assistance Systems (ADAS) especially designed to support older drivers crossing intersections might counteract these difficulties. In a longer-term driving simulator study, the effects of an intersection assistant on driving were evaluated. 18 older drivers (M = 71.44 years) returned repeatedly completing a ride either with or without a support system in a driving simulator. In order to test the intersection assistance, eight intersections were depicted for further analyses. Results show that ADAS affects driving. Equipped with ADAS, drivers allocated more attention to the road center rather than the left and right, crossed intersections in shorter time, engaged in higher speeds, and crossed more often with a critical time-to-collision (TTC) value. The implications of results are discussed in terms of behavioral adaptation and safety.     

Does early training improve driving skills of young novice French drivers?

The aim of this research was to study drivers’ performances and divided attention depending on their initial training. The performances of young novice drivers who received early training, traditionally trained drivers and more experienced drivers were compared during a dual task consisting of a simulated car-following task and a number’ parity judgment task. It was expected that, due to their limited driving experience, the young novice drivers would have more difficulty in adequately distributing their attention between the two tasks. Poorer performances by novice drivers than experienced drivers were therefore expected. The results indicate that traditionally trained drivers had more difficulties in speed regulation and maintaining their position in the lane than drivers with early training and experienced drivers. Performance impairment linked to driving inexperience was also found in the secondary task. The results were interpreted regarding the attentional resources involved in driving with a secondary task and supported the positive effects of French early training.     

Are aggressive people aggressive drivers? A study of the relationship between self-reported general aggressiveness, driver anger and aggressive driving

In this study the relationships among self-reported general aggressiveness, impulsiveness, driver anger, and aggressive responses to anger-provoking situations on the road were studied. The British version of a driver anger scale (UK DAS), aggression questionnaire (AQ), and an impulsiveness questionnaire (I7) together with background questions (gender, age, annual mileage) were administered to a sample of 270 British drivers. Variation in strength of correlations between anger and aggressive reactions in the 21 UK DAS items showed that the relationship between driver anger and aggression depends in part on the characteristics of the situation. In addition, three path models for describing the relationships among the measures were constructed separately for women and men. The models suggested that the effects of verbal aggressiveness on self-reported driver aggression were mediated by driver anger whereas physical aggressiveness was directly related to aggressive behaviour. Age was negatively related to both driver anger and aggression among men whereas annual mileage was negatively related to aggression among women. The models constructed indicate that aggressive driver behaviour is a complex phenomenon with a range of psychological causes.     

Why have fatality rates among older drivers declined? The relative contributions of changes in survivability and crash involvement

ObjectivesThis study examined the trend in fatality rates per vehicle miles traveled (VMT) among older drivers relative to middle-aged drivers and quantified the contributions of changes in crash involvement and survivability to this trend.MethodsUsing U.S. national databases, changes in driver deaths per crash involvement (marker of death risk when involved in a crash) and crash involvements per VMT (marker of crash risk) from 1995–1998 to 2005–2008 among older drivers aged 70 and over relative to changes among middle-aged drivers aged 35–54 were computed. The contributions of these components to the relative changes in older drivers’ fatality rates per VMT were calculated using the decomposition methodology.ResultsFatality rates per VMT declined more among older drivers than among middle-aged drivers over the study period. Relative to middle-aged drivers, drivers aged 75 and older experienced large declines in crash risk and modest declines in death risk. Relative declines in crash risk accounted for 68–74% of the larger decline in fatalities per VMT among drivers aged 75 and older compared with middle-aged drivers. Drivers aged 70–74 experienced modest relative declines in crash risk and death risk. Declines in death risk among drivers aged 75 and older relative to middle-aged drivers were much larger in side-impact crashes; improvements in crash survivability accounted for nearly half of the relative decline in fatality rates in these crashes. Relative survivability did not change significantly in frontal impacts. Higher death risk was more important than higher crash risk in explaining older drivers’ elevated fatality rates per VMT relative to middle-aged drivers during 1995–1998, and the contribution of heightened death risk was even greater during 2005–2008.ConclusionsMany factors may have reduced crash involvements among drivers 75 and older, including changes in travel patterns, health, and roadway design. In side impacts, side airbags and reduced passenger vehicle incompatibility may have improved survivability for older drivers. Because excess fragility now makes an even larger contribution to older drivers’ elevated fatality rates, future countermeasures that improve survivability can likely provide large benefits.     

Does presence of social media plugins in a journal website result in higher social media attention of its research publications?

Scientometrics - Social media platforms have now emerged as an important medium for wider dissemination of research articles; with authors, readers and publishers creating different kinds of social...     

What are the differences in driver injury outcomes at highway-rail grade crossings? Untangling the role of pre-crash behaviors

Crashes at highway-rail grade crossings can result in severe injuries and fatalities to vehicle occupants. Using a crash database from the Federal Railroad Administration (N = 15,639 for 2004–2013), this study explores differences in safety outcomes from crashes between passive controls (Crossbucks and STOP signs) and active controls (flashing lights, gates, audible warnings and highway signals). To address missing data, an imputation model is developed, creating a complete dataset for estimation. Path analysis is used to quantify the direct and indirect associations of passive and active controls with pre-crash behaviors and crash outcomes in terms of injury severity. The framework untangles direct and indirect associations of controls by estimating two models, one for pre-crash driving behaviors (e.g., driving around active controls), and another model for injury severity. The results show that while the presence of gates is not directly associated with injury severity, the indirect effect through stopping behavior is statistically significant (95% confidence level) and substantial. Drivers are more likely to stop at gates that also have flashing lights and audible warnings, and stopping at gates is associated with lower injury severity. This indirect association lowers the chances of injury by 16%, compared with crashes at crossings without gates. Similar relationships between other controls and injury severity are explored. Generally, crashes occurring at active controls are less severe than crashes at passive controls. The results of study can be used to modify Crash Modification Factors (CMFs) to account for crash injury severity. The study contributes to enhancing the understanding of safety by incorporating pre-crash behaviors in a broader framework that quantifies correlates of crash injury severity at active and passive crossings.     

Does hemodiafiltration improve the removal of homocysteine?

High prevalence of hyperhomocysteinemia is common in hemodialysis (HD) patients and could contribute to worsen the cardiovascular risk. Beyond vitamin B status, dialysis modality itself could influence homocysteine (Hcy) levels. The objective was compare the reduction rate (RR) of Hcy and cysteine in stable dialyzed patients treated by standard HD or hemodiafiltration (HDF). Seventy‐five patients undergoing stable dialysis through standard high‐flux HD (n = 35) or HDF (n = 40) were included. Biological parameters were determined before and after a midweek dialysis session. Urea percent reduction per session and Kt/V index (K, body urea clearance, T, time of dialysis, and V, urea distribution volume), defined as a marker of dialysis efficacy, were similar between HD and HDF groups. By contrast, higher RR of beta2 microglobulin (β2m) was observed in HDF compared with HD (78.6 vs. 72.0%, respectively; P < 0.001). Likewise, higher RR of Hcy was obtained with HDF compared to HD (46.0 vs. 41.5%, respectively; P < 0.05), whereas the RR of cysteine was similar in both groups. Interestingly, a positive correlation between Hcy RR and urea Kt/V index was observed (r = 0.29, P < 0.05) and between Hcy RR and β2m RR (r = 0.45, P < 0.001). Time‐averaged concentration (TAC) of Hcy was lower with HDF compared with HD (17.8 vs. 19.1 μmol/L, respectively), although not significant. There was no difference in median Hcy according to dialysis modality for neither pre‐ nor postdialysis levels. Significant higher removal of Hcy was observed with HDF compared with standard HD, although urea Kt/V index was similar. Enhanced removal of middle molecules, such as β2m, could be involved in Hcy RR improvement with HDF.     

Does the domain of technology impact user trust? Investigating trust in automation across different consumer-oriented domains in young adults,military, and older adults

Trust has been shown to be a determinant of automation usage and reliance. Thus, understanding the factors that affect trust in automation has been a focus of much research. Despite the increased appearance of automation in consumer-oriented domains, the majority of research examining human-automation trust has occurred in highly specialised domains (e.g. flight management, military) and with specific user groups. We investigated trust in technology across three different groups (young adults, military, and older adults), four domains (consumer electronics, banking, transportation, and health), two stages of automation (information and decision automation), and two levels of automation reliability (low and high). Our findings suggest that trust varies on an interaction of domain of technology, reliability, stage, and user group.     

Industry 4.0 and resilience in the supply chain: a driver of capability enhancement or capability loss?

The purpose of this research is to develop a better understanding of smart systems and autonomous processes of the Industry 4.0 era. Does the implementation of Industry 4.0 processes and systems expose firms to higher levels of risk in the supply chain through capability loss or does Industry 4.0 spur capability enhancement and thereby increase supply chain resilience? Industry 4.0 is centred on the idea that certain tasks and decisions can be automated through smart systems and autonomous processes. However, is there a risk of losing critical capabilities and the ability to be flexible, agile and resilient to unexpected disruptions in the supply chain? In order to address these questions, this research presents results from semi-structured interviews across multiple industries to provide findings on firms’ uses of smart systems and capability development associated with these systems. Results from this exploratory study may be classified into two primary insights. First, although Industry 4.0 systems are new and, in many cases untested, firms are eager regarding the potential of smart systems to positively impact firm performance and to leverage Industry 4.0 processes for a competitive supply chain advantage. Second, companies did not claim any human capability loss associated with Industry 4.0. In fact, these smart systems may lead to increased supply chain resilience because of capability enhancement and new skill development.     

Ageing drivers: storm in a teacup?

The purpose of this paper is to address two important issues regarding ageing drivers. First, there is a presumption in the road safety arena that the expected increase in the number of ageing drivers on the roads will lead to an increase in crashes. Second, despite extensive research on ageing drivers, especially on their increased vulnerability and reduced driving abilities, the most widely recommended road safety strategy relates to the control of their driving licenses. This presumption and the associated policy recommendation are based mainly on the higher relative crash risks associated with ageing drivers compared to their younger counterparts. This study, however, argues that the average crash risks obtained in previous studies provide only indirect information concerning these issues and any decision based on these results may produce unexpected outcomes. An analytical framework to examine the marginal effect of changing the driver mix on the roads is proposed and a simple empirical model is estimated as an illustration. In contrast to previous studies, we found that increasing the number of licenses issued to ageing drivers had only an insignificant impact on the number of fatal crashes on the roads, suggesting that the concern over ageing drivers may be a storm in a teacup.