Road Safety Outcomes Research Articles

Analyzing the Impact of Alcohol on Driving Performance and Road Traffic Accidents: Evidence from Simulations and Limited-Time Data from Bangladesh

This study evaluated the effects of alcohol consumption on driving performance and its contribution to road traffic accidents using simulated experiments and real-world data from 2016 to 2018. The simulated experiments involved 25 drivers, revealing significant impairments in reaction time, vigilance, perception, and control at varying blood alcohol concentration (BAC) levels. Higher BAC levels were associated with increased accident rates, with statistical analysis demonstrating a linear trend between BAC and performance metrics such as average speed (p < 0.05), speed variability (p < 0.01), and lane position deviation (p < 0.01). Real-world data indicated a total of 6,114 accidents in 2016, 5,345 in 2017, and 5,367 in 2018, with a notable decline in serious and fatal accidents by 2018 (fatal accidents decreased from 2,197 in 2016 to 219 in 2018). However, slight accidents rose sharply from 2,662 in 2017 to 4,673 in 2018. Alcohol-related cases peaked at 163 in 2017 before dropping to 125 in 2018. Chi-square analysis found no statistically significant relationship between fatalities and exceeding the legal BAC limit (p = 0.1013 for 2016, p = 0.0981 for 2017, p = 0.1923 for 2018). The study emphasizes the persistent role of alcohol in increasing road safety risks, particularly in accident severity. These findings highlight the importance of stricter enforcement of BAC regulations, public awareness campaigns, and targeted interventions to mitigate high-risk behaviors, such as speeding and poor vehicle control, to enhance road safety outcomes.

Beyond behavior: Understanding the role of values and personality on pedestrian behaviors

Understanding pedestrian behaviors is crucial due to their responsibility for road safety outcomes. Young road users are the most vulnerable group regarding road traffic crashes. This study explores, for the first time in literature, the moderating effect of personality on the relationship between values and pedestrian behaviors among young adults using two major theories in psychology research, The Big Five Personality Model and Schwartz Value Theory. A sample of 389 young adults (Female = 261; Mage = 22.12;SD = 1.89) completed a set of questionnaires. Moderation analyses revealed that conscientiousness and neuroticism emerged as significant moderators. Specifically, increased self-enhancement is associated with more violations at low levels of conscientiousness. Conversely, a low level of conscientiousness, accompanied by increased self-enhancement and openness to change values, is associated with decreased aberrant pedestrian behaviors among young adults. High neuroticism, accompanied by increased openness to change and self-transcendence, is associated with decreased aggressive behaviors. Increased conservation is associated with higher positive behaviors at low levels of neuroticism, while higher self-transcendence is associated with fewer positive behaviors at high levels of neuroticism. The results highlight the interaction between values and personality in influencing pedestrian behaviors, which could be used in pedestrian-specific interventions and educational programs to reduce the unsafe behaviors of pedestrians. The findings are presented in detail and discussed in the context of the relevant literature.

The impact of the Korean safe rates system on work environment and road safety

Abstract The regulation of road transport supply chains has recently become a subject of international concern. A significant body of research shows that ensuring minimum rates of pay for truck drivers is important, not only to workers’ health and safety but also to achieving improved road safety outcomes and other policy objectives related to the viability of the road transport industry. For this study, we used an empirical analysis to quantitatively demonstrate the impact of South Korea’s Safe Rates System on factors of the work environment and driver behaviours that affect road safety. Specifically, we looked at the impact of the system on market structure, truck drivers’ monthly net income, average working time, time spent on maintenance, and the frequency of overloading, speeding, and drowsiness while driving. Our results suggest that increased rates of pay for owner truck drivers resulting from the implementation of the Safe Rates System led to a reduction in the average number of contracting steps between client companies who ship goods and the truck drivers who transport them, improvement in the level of market transparency, increased monthly income, decrease in total time worked, decrease in the frequency of overloading, speeding, and drowsiness while driving, and increase in time spent on vehicle maintenance. The level of compliance with the system by clients and transport companies also had an overall positive impact on the industry structure. By empirically demonstrating the system’s impact, our results provide statistical evidence useful to the debate on reintroduction of the Safe Rates System in Korea.

Role of Culture, Income Level and Governance Quality on Driver Behaviours

The regional differences in road safety parameters have been attributed to cultural and economic factors. Nevertheless, there are differences in road safety outcomes between countries with similar cultural backgrounds and income levels. The current study examines this fact by considering the role of governance quality in the relationship between culture, income level, and driver behaviours. In this study, we modelled driver behaviour scores from 65 countries with Hofstede’s cultural dimensions, Schwartz’s cultural values, and the worldwide governance indicators from the World Bank’s database. Hayes’ PROCESS macro was utilised to analyse the moderation roles of governance quality and income level in the relationship between culture and driver behaviours. High governance quality can prevent or discourage drivers to commit non-speeding violations. Governance quality could regulate the relationship between cultural variables, income level, and driver behaviours. The Power Distance dimension was associated with non-speeding violations in high-income countries with medium or low governance quality. The embeddedness value was associated with speeding behaviours in countries with low governance quality and high/medium income. Governance quality is a critical factor of road safety in high- and middle-income countries. Where there is a lack of qualified governance to establish and enforce rules and individuals have access to social and material power, the culture becomes the determinant of aberrant driver behaviours. This is the first study relating governance quality to driver behaviours at the country level. The implications and limitations of the study were acknowledged.

Multigroup invariance of measure for angry drivers (MAD) scale using a representative sample of drivers in Australia

Introduction: Driver anger and aggression have been linked to crash involvement and injury outcomes. Improved road safety outcomes may be achieved through understanding the causes of driver anger, and interventions designed to reduce this anger or prevent it from becoming aggression. Scales to measure anger propensities will be an important tool in this work. The measure for angry drivers (MAD; Stephens et al., 2019) is a contemporary scale designed to measure tendencies for anger across three types of driving scenarios: perceived danger from others, travel delays, and hostility or aggression from other drivers. Method: This study aimed to validate MAD using a representative sample of Australian drivers, stratified across age, gender, and location. Participants completed a 10-minute online survey that included MAD, sought demographic information (age, gender, driving purpose, crash history), as well as the frequency of aggressive driving. Multigroup confirmatory factor analyses (MGCFA) assessed how stable the structure of the MAD was across drivers of different ages, gender, purposes for driving and those who do or do not display anger aggressively. MAD was invariant across all groups, showing that all drivers interpreted and responded to MAD in the same way. Results: A comparison of latent means showed anger tendencies were higher for men compared to women, for younger drivers compared to older drivers, and for those who drive mainly for work compared to those who mainly drive for other reasons. When controlling for driver factors, driving anger was associated with increased odds of being aggressive while driving. Practical Applications: Overall, this study demonstrated that MAD is an appropriate scale to measure anger tendencies and can be used to support interventions, and evaluation of interventions, to reduce anger and aggressive driving.

Developing improved crash prevention approaches through in-depth investigation of motorcycle crash causation patterns

Despite advancements in road safety, Powered Two-Wheelers (PTWs) remain a vulnerable group with disproportionately high crash rates. This paper presents an in-depth analysis of PTW crashes in six European countries, with a case study of Loss of Control in Curves (LoCC), to address the gap between crash causation and prevention. By examining crash causation factors and their linkage to prevention strategies, the study illustrates various approaches for connecting causes and countermeasures. These approaches, which are applicable to different crash scenarios, include looking forward in the crash causation chains, looking backward, looking at only the last cause (critical events), or the first cause, or following a systemic approach. The research introduces a set of guidelines following the safe system approach, aiming to enhance the understanding of crash prevention among policymakers. The systemic approach to countermeasures, bridges the shortcomings of traditional crash causation studies that may exhibit bias or a narrow focus on “root causes”. The proposed approach emphasizes the need for a comprehensive view of crash scenarios (i.e., considering the entire crash causation chain or multiple causation chains) and ensuring that preventive measures address the full spectrum of the system. It also takes in to account external factors such as cost, benefits, and politics, leading to improved road safety outcomes. The study findings are significant for researchers, since it is a step forward in in-depth crash causation studies, as well as road practitioners and policymakers, in providing a strategic framework for more effective and efficient road safety interventions.

The impact of methamphetamine use and dependence: A systematic review on the cognitive-behavioural implications for road safety

Methamphetamine (MA) users are over-represented in vehicle crash statistics but under-represented in the road safety research literature. This systematic review evaluates the current research base relating to MA use and its associated cognitive-behavioural outcomes; and aims to discuss the implications that these findings may have towards driving and future road safety research directions. Following PRISMA guidelines, a literature search was conducted on research studies using six different databases. Inclusion criteria were acute and chronic MA use in humans, with outcome variables relating to cognitive performance, behavioural tendencies, or psychopathology. Primary exclusion criteria included outcomes that were not directly translatable to road safety outcomes (e.g., health) or very specific samples that may have confounded the effects of MA use (e.g., prisoners). In total, 101 publications met the criteria for inclusion in the review. The literature showed that firstly, acute use (but not abuse) of MA may lead to cognitive enhancements, although these findings are not likely translatable to real-world use. Secondly, evidence suggested that chronic MA use is associated with cognitive impairments, self-regulatory difficulties, and increased aggression, suggesting that MA users may be at a significantly increased risk on the road, in a variety of domains. In addition, chronic MA use has been linked to a range of psychological issues (e.g., psychosis; anxiety; depression), which may exacerbate the negative cognitive-behavioural effects of MA. Finally, abstinence from MA was shown to reduce the aversive impacts of chronic MA use, although cognitive improvements have been demonstrated to take much longer, compared to behavioural and psychopathology conditions. The limitations associated with the current MA literature base were evaluated and methodological suggestions were made for future research to better understand the effect of MA use patterns on driving performance and behaviour.

Impact of Speed Limit Enforcement Cameras on Speed Behavior: Naturalistic Evidence from Brazil

Speeding is widely recognized as a key contributor to the occurrence and severity of road crashes, making studies on speed reduction devices particularly relevant given poor road safety outcomes worldwide. This study investigates the impact of fixed speed cameras on driver behavior and speed reduction in urban arterials using a naturalistic driving study methodology. Data from 13 drivers and 116 trips in Curitiba, Brazil, were analyzed, with a focus on speed cameras placed on arterial roads. Speed data were grouped and analyzed by various categories, including topographic profile, day and week periods, and rain conditions. Mean comparisons were used to compare data sets, revealing an overall speed reduction effect of 0.69 km/h (−1.33%) around the speed camera. The study identified a pattern of punctual speed reduction, known as a “kangaroo jump,” a speed reduction followed by an increase in speed, referred to as the “compensation effect,” and a new pattern characterized by a non-significant speed reduction at the speed camera site followed by an increase in speed, referred to as the “cobra strike effect” because of its curve pattern. The largest speed reductions were observed for flat topographic profiles (−2.98%), daytime travel (−1.58%), and travel on working days (−1.75%) with rain (−1.80%). Conversely, the speed camera had little impact on vehicle speed for uphill topographic profiles, no rain conditions, and travels during weekend.

Traffic safety for all road users: A paired comparison study of small & mid-sized U.S. cities with high/low bicycling rates

Cities with high levels of bicycling tend to be some of the safest cities for all road users. This paper investigates why this relationship exists for fourteen small and mid-sized cities across the U.S. (seven with high bicycling rates and seven paired comparison cities) using ten years of data and hierarchical negative binomial regression models. Findings confirm that higher-bicycling cities are significantly associated with better overall road safety outcomes. In terms of mode choice differences, pedestrian ‘safety in numbers’ as well as reduced driving activity had a positive impact on pedestrian safety. Results from hierarchical negative binomial regressions also suggest that more compact cities were significantly associated with better road safety outcomes for all road users. In terms of socio-demographic and socio-economic factors, the results reveal equity concerns with areas with lower incomes and more non-White residents seeing more overall road fatalities.

Android accident detection and alert system

Android smartphone app will automatically detect the accident that will be occurred. The app immediately retrieves the GPS location and activates an alarm screen. With one tap, the user can request emergency assistance. The app calls the local emergency number and sends SMS alerts to predefined contacts. The alerts provide accident details including location coordinates, number of passengers, and crash characteristics. Development challenges include accurately identifying crashes across varying conditions while minimizing false positives, integrating with onboard vehicle systems for additional data, addressing cybersecurity risks, optimizing for minimal battery usage, and easing privacy concerns over data collection. If technical obstacles can be overcome, such an automated crash detection and emergency alert app could help expedite emergency responses and improve road safety outcomes. Intended as an low-cost, scalable supplementary crash alert system, it has the potential to save lives worldwide.

How to Successfully Engage a Community in Road Safety

Lack of community engagement in road safety issues has been a difficult barrier to achieving greater road safety outcomes. In this project, our aim was to develop a road safety campaign that humanises cyclists. We devised a four-step approach to develop and implement the campaign to engage the community and achieve positive outcomes. The four steps were: 1) key stakeholder engagement, 2) community consultation, 3) campaign creation and delivery and, 4) evaluation. As this project was conducted in 2020/2021, we address how we managed disruptions caused by COVID-19. Key findings show the campaign was successful and increased understanding of safe behaviours and positive influence on attitudes about cyclists. The frameworks used for this project are provided and while the insights from this project apply to cyclist safety, the steps can be applied to improve collaborative projects to include community engagement in any area of road safety.

Anytime, anywhere: Understanding random breath testing deployments at the local level

The impact of random breath testing (RBT) on alcohol-related traffic crashes has been the subject of numerous studies over the past 30 years. The existing body of research clearly identifies the positive impact of RBT programmes around the world. However, very little is known about when and where RBT is deployed locally to achieve the desired outcomes. By understanding how RBT is being deployed in space and time opportunities may be identified to improve current practices. To start addressing this gap, the current paper characterises the location and timing of RBT within a Queensland Police District. Results identify RBT is more likely to be conducted within specific locations, on particular days and at particular times. These outcomes provide a level of clarity over the operationalisation of RBT, offering opportunities to explore how this strategy could be varied to try and improve road safety outcomes, for example, increasing the diversity of RBT locations or evening out the number of tests conducted each day of the week to increase the perceived certainty of sanctions. The results also have implications for future research. Of interest would be the impact of RBT predictability on perceptions of avoidance. The repeat police presence also provides an opportunity for future research to explore a potential diffusion of benefit, crime reduction. These implications are discussed, within the context of the extant literature, to guide future research aiming to maximise the efficacy and efficiency of RBT programmes.

Short‐ and long‐run impacts of gasoline price and macroeconomic factors on road traffic safety in Nigeria

AbstractThis paper examined the short‐ and long‐run impacts of gasoline price, macroeconomic factors and road length on road traffic crashes, injuries and fatalities in Nigeria. Annual data from 1995 to 2019 and autoregressive distributed lag approach were employed. Results suggest that gasoline price, per capita income, road length and population density significantly influence road safety outcomes. Gasoline price has a positive short‐run impact on crashes, injuries, and fatalities contrary to findings in developed countries. Road crashes tend to decrease when income increases in the short term. Population density leads to improvement in road safety outcomes while road length exacerbates it. Government's policy on gasoline price increase could worsen road safety outcomes unless it is accompanied by improvement in road infrastructure, safe public transport and economic growth,

The influences of strict and post-strict lockdowns due to the Covid-19 pandemic on crash severity on rural roads: A case study of Khorasan Razavi, Iran

Covid-19 has influenced traffic patterns due to restrictions on travel. During COVID-19 restrictions, many people opted to travel by private cars for their mandatory trips instead of using public transportation, while many non-essential trips were cancelled. The changes in travel restrictions have influenced road safety outcomes. Utilizing decision tree modelling, the current research seeks to evaluate the impact of the COVID-19 pandemic on the severity of road traffic crashes, considering two severity levels: fatal and non-fatal crashes in Iran's Khorasan Razavi province. The analysis considers the time period from May 2019 to October 2021 and includes three main intervals: the pre-COVID-19, strict lockdown period, and post-strict lockdown period. A spatial–temporal analysis of crash data was performed utilizing a data fusion approach with results presented using a Classification and Regression Tree (CART) model. The data fusion approach uses a variety of data sources in order to obtain a thorough overview of the phenomenon being studied. In this study, independent descriptive factors, such as geometric design, weather, temporal variables, driver behavior, crash type, and traffic attributes, were included in the analysis. A similar pattern for crash severity was observed during the pre-COVID-19 and post-strict lockdown phases, with the majority of crashes being non-fatal. However, fatal crashes were more prevalent during the strict lockdown period. Among the independent variables associated with fatalities were traffic volume. In this study we identified that higher traffic volumes resulted in a higher crash frequency, however they were also associated with lower speeds, resulting in a decline in the severity of crashes. Other variables included lack of awareness as a driver behavior and cloudiness as a weather condition.

Road safety and road infrastructure expenditure: A bivariate analysis

A considerable body of earlier literature has analysed the determinants of road safety outcomes at the aggregate level. A sub-set of that literature has sought to assess the effect of road expenditure, both investment and maintenance spending, on road safety. The results have been inconclusive and, in part, counterintuitive. To clarify that relationship, this paper undertakes a bivariate analysis using European panel data. Three main results emerge. First, there is only limited evidence of longer-term relationships (common stochastic trends) among different measures of the variables. Second, causality tests on stationary variables suggest that the direction of causality depends on how the variables are measured. Third, unrestricted Vector Autoregression (VAR) analyses suggest that there is a positive relationship from some measures of road safety outcomes to road infrastructure investment, and that an increase in one real measure of road infrastructure investment reduces fatalities permanently, if with a lag. While not modelling the true and complex data generating processes, these bivariate analyses help address the salient empirical issues emerging from earlier literature, and the results provide a detailed description of the relationship between road safety and infrastructure expenditure.

A Review of Surrogate Safety Measures Uses in Historical Crash Investigations

Historical road crash data are the main indicator for measuring road safety outcomes. Over the past few decades, significant efforts have been made in obtaining and exploiting Surrogate Safety Measures (SSMs). SSMs have the potential to provide excellent sustainable road safety indicators and proxy measurements which can complement traditional historical crash analyses or even substitute them. By using SSMs, crash data collection demands can be bypassed and areas can be investigated before crashes occur. Due to such advantages, the objective of the present research is to provide a review of the scientific literature regarding studies exploiting SSMs for historical crash record investigations. Specifically, 34 studies were examined, providing insights on the different types of SSMs collected under real road environment conditions, the way they are collected, their connection with specific road crash types, and the type of the developed statistical models are examined and discussed. Particular focus is also placed on the temporal dimension of the collection period of both SSMs and road crashes. Finally, the overall trends deriving from the reviewed studies are summarized and future research directions are provided.

Did the cannabis recreational use law affect traffic crash outcomes in Toronto? Building evidence for the adequate number of authorised cannabis stores' thresholds.

In the past decade, a group of studies has begun to explore the association between cannabis recreational use policies and traffic crashes. After these policies are set in place, several factors may affect cannabis consumption, including the number of cannabis stores (NCS) per capita. This study examines the association between the enactment of Canada's Cannabis Act (CCA) (18 October 2018) and the NCS (allowed to function from 1 April 2019) with traffic injuries in Toronto. We explored the association of the CCA and the NCS with traffic crashes. We applied two methods: hybrid difference-in-difference (DID) and hybrid-fuzzy DID. We used generalised linear models using CCA and the NCS per capita as the main variables of interest. We adjusted for precipitation, temperature and snow. Information is gathered from Toronto Police Service, Alcohol and Gaming Commission of Ontario, and Environment Canada. The period of analysis was from 1 January 2016 to 31 December 2019. Regardless of the outcome, neither the CCA nor the NCS is associated with concomitant changes in the outcomes. In hybrid DID models, the CCA is associated with non-significant decreases of 9% (incidence rate ratio 0.91, 95% confidence interval 0.74,1.11) in traffic crashes and in the hybrid-fuzzy DID models, the NCS are associated with nonsignificant decreases of 3% (95% confidence interval - 9%, 4%) in the same outcome. This study observes that more research is needed to better understand the short-term effects (April to December 2019) of NCS in Toronto on road safety outcomes.

Alcohol and driving—How bad is the combination? A meta-analysis

Objective The objective of this study was to summarize existing knowledge on the association between driving under the influence of alcohol and road safety outcomes and to assess factors that may explain why these estimates vary. Methods Based on studies of the association between blood alcohol concentration (BAC) levels and crashes, we used multilevel metaregression to calculate summary effects of BAC level and analyze potential moderators of the association. Results Based on 60 studies and 393 effect estimates, we found that BAC level, outcome severity, use of hospital data, and geographical region contributed to heterogeneity in results. Conclusion The effect of BAC on crash and injury risk and culpability is stronger at higher BAC levels and for more serious outcomes. The relationship between BAC level and outcome is approximately exponential. The relationship is stronger in studies from Nordic countries than in studies from other countries, possibly because of the relatively low level of drunk driving in these countries. Studies based on hospital data and studies using non-crash-involved control groups find smaller effects on average.

Reexamination of the association between development patterns and truck crashes: A case study in Dallas-Fort Worth, TX

Over the last decade, urban logistics operations have changed significantly due to globalized production and distribution systems and expanding online shopping sales. On the one hand, goods are distributed on a greater scale through large-scale transportation infrastructure. On the other, exploding online shopping shipment has added another layer of complexity to urban logistics operations. Nowadays, instant home delivery has become prevalent. Provided that the geography, extent, and frequency of freight trip generation have completely changed, it can be assumed that the relationship between the development pattern characteristics and road safety outcomes has also changed, accordingly. Then, it is imperative that the spatial distribution of truck crashes, in conjunction with development pattern characteristics, is reexamined. As a Dallas-Fort Worth, TX metro area case study, this research examines whether the spatial distribution of truck crashes on city streets is different from that of other vehicle crashes and tests whether truck crashes have a unique association with development patterns. Results show that truck and passenger car crashes are distinguished in terms of how they are associated with urban density and employment sector compositions. The explanatory variables with significant and expected signs of relationship are VMT per network mile (exposure), intersection density, household income, % non-white, and % no high school diploma. Results indicate that the spatial heterogeneity in goods shipment intensity has strong implications for the variation in truck crash patterns. Results also call for a comprehensive reexamination of trucking activity in dense urban areas.

The role of safety in modal choice and shift: A transport expert perspective in the state of Victoria (Australia).

Previous research showed differences in the exposure to risk from using different modes of transport and that modal choice can significantly impact road safety outcomes. Though, a modal shift to a safer mode is not commonly discussed as part of road safety strategies. This study aimed to explore the perspectives of transport policymakers about the role of safety in modal choice and if it can be one of the main factors for modal choice and shift. Seven semi-structured interviews were conducted with transport experts from government (n = 5) and private (n = 2) organisations in the state of Victoria. Interview transcripts were analysed using a thematic approach to identify the key perspectives of the experts. Overall, the analyses indicated uncertainty of the ability to use safety in modal choice as a road safety strategy and identified two main issues; 1) the perceived limited role that safety plays in people's modal choice, and 2) that safety is perceived to be a barrier to modal choice and modal shift towards public and active travel. Experts suggested that when considering transport modes other factors such as convenience, availability, speed, cost, trip purpose and income are more influential than safety in modal choice. They also suggested that safety might play a role within the chosen mode, but not in choosing between modes, such as considering safety features when purchasing a car after deciding to drive a car. It was also stated that safety could act as a barrier preventing people from choosing sustainable transport modes of public transport and active travel. Theoretically, it is argued that safety and mobility cannot be traded against each other, and that mobility becomes a function of safety, not vice-versa. However, our findings indicated that the transport experts did not believe that safety is the main factor in the modal choice process. Transport experts believed users choose their mode of transport mainly to achieve mobility benefits without necessarily considering how safe is their choice as a differentiator factor. While the shift to a safer mode of transport would help improve road safety outcomes, further investigations are needed to inform how can we influence the consideration of safety as the main factor in modal choice and removing barriers to using the relatively safest available mode of transport.