Perception of safety of cyclists in Dublin City

Assessing bicycle safety risks using emerging mobile sensing data

The surge in global electric bicycle ownership has exerted immense pressure on bicycle infrastructure. Theoretically, there's a need to reassess the risk factors associated with multiple bike lane users. Based on this, there's a practical need to re-evaluate the safety and quality of outdated infrastructure. This paper aims to reconsider risk factors related to bicycle infrastructure safety in the context of electric bicycles sharing lanes with traditional bicycles. Moreover, many countries lack precise spatial data concerning bicycle infrastructure. This study introduces a mobile sensing method based on bicycles, aiming to acquire daytime and nighttime bike lane datasets in a cost-effective, efficient, and large-scale manner. A computer vision-based bicycle risk factor assessment model was established, and the distribution of bicycle safety risk factors was visually analyzed. Research data was collected from a representative 59.5-kilometer bicycle lane area in Beijing. The results confirm the significant impact of the surge in electric bicycles, with electric bike users accounting for 72.1% of cyclists, 32.3% wearing helmets, and 8.4% riding against traffic. During the day, the highest-ranking risk factors include the type of bicycle lanes (half lacking dedicated lanes or being shared), roadside parking, and subpar road conditions. At night, insufficient street lighting are notable concerns. The research methodology is easily replicable and can be extended to new multi-user coexistence cycling environments or countries without bicycle spatial data, offering insights for bicycle safety policies and road design.

Computer vision and statistical insights into cycling near miss dynamics

Across the globe, many transport bodies are advocating for increased cycling due to its health and environmental benefits. Yet, the real and perceived dangers of urban cycling remain obstacles. While serious injuries and fatalities in cycling are infrequent, "near misses"-events where a person on a bike is forced to avoid a potential crash or is unsettled by a close vehicle-are more prevalent. To understand these occurrences, researchers have turned to naturalistic studies, attaching various sensors like video cameras to bikes or cyclists. This sensor data holds the potential to unravel the risks cyclists face. Still, the sheer amount of video data often demands manual processing, limiting the scope of such studies. In this paper, we unveil a cutting-edge computer vision framework tailored for automated near-miss video analysis and for detecting various associated risk factors. Additionally, the framework can understand the statistical significance of various risk factors, providing a comprehensive understanding of the issues faced by cyclists. We shed light on the pronounced effects of factors like glare, vehicle and pedestrian presence, examining their roles in near misses through Granger causality with varied time lags. This framework enables the automated detection of multiple factors and understanding their significant weight, thus enhancing the efficiency and scope of naturalistic cycling studies. As future work, this research opens the possibility of integrating this AI framework into edge sensors through embedded AI, enabling real-time analysis.

Are bicycle streets cyclist-friendly? Micro-environmental factors for improving perceived safety when cycling in mixed traffic

A bicycle street is a mixed traffic street where motor vehicles are forced to adapt their speed to bicycle traffic, for example by encouraging cycling in the middle of the street using centered bicycle lanes. The objective safety of cyclists increases with lower vehicle speeds and fewer motor vehicles. Despite this, cyclists' perception of their safety is often reduced in mixed traffic streets. Subjective unsafety and risk constitute a major barrier to increased cycling. This study investigates how the design of the micro-environment of bicycle streets can improve cyclists' perceived safety in mixed traffic. A quasi-experimental survey in which 371 participants rated their perceived safety in photo-manipulated bicycle streets was conducted. 52% of the participants were male, the mean age was 43 (20-77) years, and 76% reported that they cycle 4-5 days a week or more. The focus was on evaluating micro-environmental factors such as different designs of centered bicycle lanes, road markings, signs, traffic volume, and parked cars. It is concluded that the micro-environment has important effects on the perceived safety of cyclists. Important gains in subjective safety can be achieved with fairly simple design efforts. Many participants felt safe when there were clearly demarcated red-colored bicycle lanes in the center of the street accompanied by road markings for cyclists. The strongest effect, however, comes from reducing traffic volume. Most participants felt safe in micro-environments in which the traffic volume had been reduced, including those where no design changes had been made. Important differences between different groups of cyclists were also found.

CYCLANDS: Cycling geo-located accidents, their details and severities

Several cities and national authorities across the globe publish records on road accidents and crashes. This data is vital for road safety analysis, enabling researchers to develop models to understand how different factors impact the frequency and severity of accidents. However, researchers studying cycling safety face additional challenges as datasets containing solely cycling accidents are scarce, may contain errors, among others. Thus, we publish CYCLANDS: CYCling geo-Located AccideNts, their Details and Severities. CYCLANDS is a curated collection of 30 datasets on cycling crashes to lower the barrier in objective cycling research comprising nearly 1.6 M cycling accidents. All observations include the severity and location of the accident. This collection fosters the worldwide study of cycling safety by providing a testbed for researchers to develop tools and models for cycling safety analysis, ultimately improving the safety of those who cycle.

Measurement(s)	Cycling Accident
Technology Type(s)	Reports
Sample Characteristic - Location	World

Unhelmeted Injured Cyclists in a Canadian Emergency Department: Cycling Behavior and Attitudes Towards Helmet Use

Introduction

We seek to characterize unhelmeted injured cyclists presenting to the emergency department: demographics, cycling behavior, and attitudes towards cycling safety and helmet use.

Methods

This was a prospective case series in a downtown teaching hospital. Injured cyclists presenting to the emergency department were recruited for a standardized survey if not wearing a helmet at time of injury and over age 18. Exclusion criteria included inability to consent (language barrier, cognitive impairment) or admission to hospital.

Results

We surveyed 72 UICs (unhelmeted injured cyclists) with mean age of 34.3 years (range 18–68, median 30, IQR 15.8 years). Most UICs cycled daily or most days per week in non-winter months (88.9%, n = 64). Most regarded cycling in Toronto as somewhat dangerous (44.4%, n = 32) or very dangerous (5.9%, n = 4). Almost all (98.6%, n = 71) had planned to cycle when departing home that day. UICs reported rarely (11.1%, n = 8) or never (65.3%, n = 47) wearing a helmet. Reported factors discouraging helmet use included inconvenience (31.9%, n = 23) and lack of ownership (33.3%, n = 24), but few characterized helmets as unnecessary (11.1%, n = 7) or ineffective (1.4%, n = 1).

Conclusions

Unhelmeted injured cyclists were frequent commuter cyclists who generally do not regard cycling as safe yet choose not to wear helmets for reasons largely related to convenience and comfort. Initiatives to increase helmet use should address these perceived barriers, and further explore cyclist perception regarding risk of injury and death.

Influence of familiarity with traffic regulations on delivery riders' e-bike crashes and helmet use: Two mediator ordered logit models

Micro-mobility vehicles such as electric bicycles, or e-bikes, are becoming one of the essential transportation modes in metropolitan areas, and most deliveries in large cities are dependent on them. Due to the e-bike's popularity and vulnerability, e-bike crash occurrence has become a major traffic safety problem in many cities across the world; finding the most important human factors affecting e-bike safety has thus been an important recent issue in traffic safety analysis. Since delivery riders are a key group of e-bike users, and since helmet use plays a crucial role in reducing the severity of a crash, this study conducted a city-wide online survey to analyze the helmet usage of 6,941 delivery riders in Shanghai, China. To determine the in-depth mechanisms influencing helmet use and e-bike crash occurrence, including the direct and indirect effects of the relevant factors, two mediator ordered logistic regression models were employed. The mediator ordered logistic model was compared with the traditional logistic regression model, and was found to be superior for modeling indirect as well as direct influencing factors. Results indicate that riders' familiarity with traffic regulations (FTR) is an extremely important variable mediating between the independent variables of riders' educational level and age, and the dependent variables of helmet use and e-bike crashes. Improving riders' FTR can consequently increase helmet use and decrease crash occurrence. Authorities can apply these findings to develop appropriate countermeasures, particularly in legislation and rider training, to improve e-bike safety.

Subjective experiences of bicyclists being passed by motor vehicles: The relationship to motor vehicle passing distance

BACKGROUND

Feeling unsafe when riding a bicycle is a key barrier to cycling participation. To better understand the experiences of cycling on-road, this study aimed to explore the relationship between cyclists' subjective experiences and the lateral passing distance of motor vehicles.

METHODS

An on-road observational study was conducted in Victoria, Australia. Participants had a custom device installed on their bicycle that measured the lateral passing distance of motor vehicles and included a handlebar mounted "panic button" that participants could press when they felt that a passing event was too close or unsafe. A random effects logistic regression model was used to investigate the relationship between cyclist sex, motor vehicle type and infrastructure characteristics, and button press events.

RESULTS

A total of 217 button press events were recorded (1.2 % of all passing events) from 60 participants. For events with a passing distance closer than 100 cm, 10.4 % of these events had a recorded button press. The adjusted odds of a button press event were over three-fold higher when the rider was passed by a truck, compared to when the rider was passed by a sedan. The predicted probability of a button press event was higher in events occurring in road environments with no bike lane and no parked cars (1.9 %) compared to no bike lane with parked cars (1.2 %), a bike lane with no parked cars (0.9 %) and a bike lane with parked cars (0.7 %).

CONCLUSIONS

The study identified important links between cyclists' subjective experience of unsafe events, motor vehicle types and infrastructure characteristics. Greater emphasis needs to be placed on capturing subjective experiences to inform and advance the development and implementation of safe and comfortable cycling infrastructure.

Studying bicyclists' perceived level of safety using a bicycle simulator combined with immersive virtual reality

There is a need for methods that provide a better understanding of bicyclists' perceived safety and preferences on currently unavailable and/or unknown bicycle facilities. Different survey methods have been used to study bicyclists' behavior, experiences, and preferences; ranging from verbally described facilities to surveys including images and videos. Virtual Reality (VR) experiments blur the boundaries between stated preference (SP) surveys and revealed preference (RP) surveys and provide a realistic sense of design. This research introduces a novel research method in bicycling research and discusses the results of an experiment using a bicycle simulator combined with immersive VR. In total, 150 participants participated in this experiment and were asked about demographics and perceptions and preferences after bicycling in five different environments with an instrumented bicycle in VR. A 5 × 2 mixed design was used with bicycling environment as within-subject factor and pedestrian / traffic volume as between-subject factor. ANOVA tests revealed how each environment and ambient pedestrian / traffic volume affected perceived level of safety (PLOS) and willingness to bicycle (WTB). Pairwise comparison showed that participants felt safer bicycling on the segregated bicycle path compared to bicycling on the painted bicycle path on the road and roadside. There was no meaningful difference between WTB for less than 10 min and WTB for more than 10 min between bicycling on a painted bicycle path on the sidewalk and painted bicycle path on the road. PLOS and WTB ratings of men and women were not significantly different from each other. The older segment of the sample was more worried about roadside bicycling and bicycle commuters were more confident to ride on the roadside. Despite having several limitations, immersive 360-degree VR was found a powerful presentation tool to evaluate future street designs which can inform transport and urban planning.

Characteristics of cyclist collisions in Ireland: Analysis of a self-reported survey

As both a utility mode of transport and recreational activity, cycling has well-known health, environmental, and economic benefits. For these reasons it has been encouraged in many countries, including the Republic of Ireland. However, with increasing popularity there have been concurrent increases in road traffic related cyclist injuries. This study aims to characterise cyclist collisions, which are known to be underreported in Police statistics. For data collection, a survey addressing collisions was distributed to cyclists across the country in 2018. Univariable testing was used to identify differences in collision factors and injury outcomes for cyclist collisions with motorised vehicles, and those where a motorised vehicle is not involved as a collision partner i.e. single cyclist, cyclist-pedestrian, or cyclist-cyclist collisions. Furthermore, binary logistic regression modelling was used to clarify biasing factors for Police reporting of collisions. The largest proportion of collisions was between cyclists and motorised vehicles (56%), followed by single cyclist collisions (29%), collisions with other cyclists (8%), and pedestrians (7%). The odds of Police reporting for collisions with motorised vehicles in this study was 20 times greater than single cyclist collisions, 10 times greater than cyclist-cyclist collisions, and 4 times greater than collisions with pedestrians. The odds of Police reporting of serious injury collisions was 7 times greater than minor injury collisions. There were several differences in road, environmental, and human factors, and injury patterns between cyclist-motorised vehicle collisions and non-motorised vehicle collisions. The findings of this study indicate that greater attention should be paid to the following underreported collision types: 1) those that do not involve collisions with motorised vehicles (single cyclist collisions in particular), which have been shown to have differing collision characteristics to motorised vehicle collisions, and 2) less severe injuries, which have been shown to be a substantial contributor to the cyclist safety problem. Furthermore, surveys have been shown to be a valuable mechanism for investigation of lower severity cyclist injuries, which are largely unrecorded in Police or hospital data.

Cycle Logistics Projects in Europe: Intertwining Bike-Related Success Factors and Region-Specific Public Policies with Economic Results

The aim of this paper is to investigate whether and which specific, distinctive characteristics of European cycle logistics projects and the corresponding supporting policies have an impact on their economic performances in terms of profit and profitability. First, we identify project success factors by geographic area and project-specific characteristics; then, we statistically test possible dependence relationships with supporting policies and economic results. Finally, we provide a value-based identification of those characteristics and policies which more commonly lead to better economic results. This way, our work may serve as a basis for the prioritization and contextualization of those project functionalities and public policies to be implemented in a European context. We found that cycle logistics projects in Europe achieve high profit and profitability levels, and the current policies are generally working well and supporting them. We also found that profit and profitability vary across the bike model utilized: mixing cargo bikes and tricycles generates the highest profit and profitability, whilst a trailer–tricycle–cargo bike mix paves the way for high volumes and market shares.

Did Safe Cycling Infrastructure Still Matter During a COVID-19 Lockdown?

The UK government introduced strict measures (including asking people to work from home and a lockdown) to slow the spread of COVID-19 by limiting people’s movement. This led to substantial reductions in traffic, making roads much safer for cyclists. This provides a unique opportunity to study the role played by safe cycling infrastructure. Many UK cities have provided cycling infrastructure to improve safety and encourage cycling. However, access to safe cycling infrastructure varies across neighbourhoods, potentially contributing to inequality. Since roads became safer due to the unprecedented reduction in traffic during the lockdown, safe cycling infrastructure may not play a significant role during this period. On the other hand, safe cycling lanes are often connected to amenities, potentially attracting cyclists even if they confer no additional safety benefit. That is, connectivity might matter more than safety. In this study, we utilised crowdsourced cycling data and regression models to examine the extent to which cycling intensity for non-commuting purposes changes with different types of cycling infrastructure in the city of Glasgow, Scotland, UK. In addition, we selected some areas with large increases in cycling intensity and examined the surrounding environments using Google Street View. Our results showed that non-commuting cycling activities increased significantly after the government interventions on both typical roads and safe cycling lanes while much higher increases were observed on safe cycling lanes than on other roads. A further analysis showed that there were large increases in cycling volumes on both typical roads and safe cycling lanes with good amenities and connectivity, highlighting the importance of these factors when building new cycling infrastructure. Since safe cycling lanes are not equally accessible to people, providing temporary cycling lanes during the pandemic considering these conditions could encourage people to cycle more, and thereby improve their health.

Risk Perception Sensitivity of Cyclists Based on the Cox Risk Perception Model

To promote the sustainable development and safety of bicycle traffic, survival analysis of the risk perception sensitivity of cyclists is proposed. The cumulative probability of survival serves as an index of risk perception sensitivity, and a Cox regression model is established. The proposed method is applied to middle school cyclists, and the factors of their risk perception are analyzed. Data are collected by questionnaire and traffic conflict survey and are quantified by factor analysis. The model results show that active and extroverted personality, negative peer influence, unsafe riding behavior intention, non-motor vehicle flow and speed, and a lack of separation facilities have negative correlations with risk perception sensitivity. Positive attitude towards traffic rules, good family education, heightened traffic safety awareness, motor vehicle flow and speed, pedestrian flow, and non-motorized lane width have positive correlations with risk perception sensitivity. The conflict type has no correlation with risk perception sensitivity. This study aims to improve the sensitivity of risk perception, prevent traffic conflicts and provide a theoretical basis for risk perception research on vulnerable traffic participants.

Exploring Motivators and Deterrents of Cycling Tourism Using Qualitative Social Research Methods and Participative Analytical Hierarchy Process (AHP)

Cycling tourism is an environmentally friendly way to explore a destination. Nowadays, it is becoming more and more popular worldwide, since it permits an in-depth communication both with nature and people. In this context, the aim of this paper is to explore, in detail, mainly the environmental motivators of cycling tourists, and their significance, in Greece, by using qualitative social research (in-depth interviews and focus groups) and participative analytical hierarchical process. The results show that regarding physical environment, the element which attracts cycle tourists the most is the variety of scenic views along their route. Existence of lakes, rivers and beaches were also valued. On the contrary, “Biodiversity” and “Untouched natural landscapes” were ranked low as a description of the quality of the natural environment. However, the rise of cycling tourism depends considerably on the appropriate infrastructure, namely roads with low slopes, appropriate quality of surfaces and cycling infrastructure. Planners, policy-makers, and competent authorities should give emphasis on the critical factors in order to enhance cycling tourism, thus resulting in positive multiplying effects such as environmental protection and economic growth.

Seasonal variation in risk perception and travel behaviour among cyclists in a Norwegian urban area

The main purpose of the article is to examine the association between risk perception and cyclists' decision as to whether to cycle during the different seasons of the year. The study on which the article is based included worry as a feeling that emerges as a result of an individual's cognitive assessment of risk, attitudes toward traffic rules, risk tolerance and safety priority. The study was based on a questionnaire survey carried out among cyclists from Trondheim Municipality in Norway (n = 291) during spring 2017. The results revealed seasonal differences in perceived risk and that risk perception was an important predictor of both the decision as to whether to cycle and the frequency of cycling during wintertime. The same results were not found for cycling during the other seasons of the year. Additionally, an association was found between risk perception and worry. The respondents were more worried when cycling in winter conditions compared with cycling in summer conditions, and worry was a strong predictor of travel mode behaviour. The authors found that when the respondents' perception of risk was very low, they were not worried and hence their behaviour was not affected. Perceived risk and worry were only associated with cycling behaviour during wintertime. These findings may be used as a guide in measures implemented to increase the number of cyclists during winter and in communications to the public about the risks linked to cycling.

Red-light running behavior of cyclists in Italy: An observational study

Accident analysis and studies on traffic revealed that cyclists' violation of red-light regulation is a typical infringement committed by cyclists. Furthermore, an association between cyclists' crash involvement and red-light violations has been found across different countries. The literature on red-light running cyclists' behavior in relation to their characteristic is still scarce. The present study, adopted an eye-observational methodology to investigates differences in cyclists' crossing behavior at intersections, with a particular attention to their demographical characteristics. The classification of cyclists' red-light behavior in risk-taking, opportunistic and law-obeying, was adopted and re-adapted to reflect more objective behaviors, eliminating any inference or judgment. Two researchers at a time observed unobtrusively at four different intersections, during morning and late afternoon peak hours, 1381 cyclists approaching the traffic light during the red phase. More than 60% of the observed cyclists violated the traffic control. Results showed that the visual search strategy displayed by the cyclists and the presence of other cyclists at the intersection are important factors in predicting the probability of red-light running behavior.

Predictors of the frequency and subjective experience of cycling near misses: Findings from the first two years of the UK Near Miss Project

Using 2014 and 2015 data from the UK Near Miss Project, this paper examines the stability of self-report incident rates for cycling near misses across these two years. It further examines the stability of the individual-level predictors of experiencing a near miss, including what influences the scariness of an incident. The paper uses three questions asked for only in 2015, which allow further exploration of factors shaping near miss rates and impacts of incidents. Firstly, a respondent's level of cycling experience; secondly, whether an incident was perceived as deliberate; and finally, whether the respondent themselves described the incident as a 'near miss' (as opposed to only a frightening and/or annoying non-injury incident). Using this data, we find a decline of almost a third in incident rates in 2015 compared to 2014, which we believe is likely to be largely an artefact due to differences in reporting rates. This suggests caution about interpreting small fluctuations in subjectively reported near miss rates. However, in both years near miss rates are many times more frequent than injury collisions. In both years of data collection our findings are very similar in terms of the patterning of incident types, and how frightening different incident categories are, which increases confidence in these findings. We find that new cyclists experience very high incident rates compared to other cyclists, and test a conceptual model explaining how perceived deliberateness, near-miss status, and scariness are connected. For example, incidents that are perceived to be deliberate are more likely to be experienced as very frightening, independent of their 'near miss' status.

Near miss experiences of transport and recreational cyclists in New South Wales, Australia. Findings from a prospective cohort study

This paper investigates events in which cyclists perceive a cycling crash is narrowly avoided (henceforth, a near miss). A cohort of 2038 adult transport and recreational cyclists from New South Wales (Australia) provided self-reported prospectively collected data from cycling diaries to allow the calculation of an exposure-based rate of near misses and investigation of near miss circumstances. During 25,971days of cycling, 3437 near misses were reported. For a given time cycling, cyclists who rode mainly for transport (compared with those who rode mainly for recreation), and cyclists with less experience (compared to those with more experience) were more likely to report a near miss; older cyclists (60+ years) were less likely to report a near miss than younger cyclists (25-59 years). Where type of near miss was recorded, 72.0% involved motor vehicles, 10.9% involved pedestrians and 6.9% involved other cyclists. Results indicate some similarities between near misses and crashes reported by this cohort during the same reporting period. A bias toward reporting near misses with motor vehicles was suggested, which likely reflects cyclists' perceptions that crashes involving motor vehicles are particularly serious, and highlights their impact on perceived safety. Given the relative rarity of crashes, and the limited breadth and depth of administrative data, collection of near miss data may contribute to our understanding of cycling safety by increasing the volume and detail of information available for analysis. Addressing the causes of near misses may offer an opportunity to improve both perceived and actual safety for cyclists.

Cycling provision separated from motor traffic: a systematic review exploring whether stated preferences vary by gender and age

In this paper, we represent a systematic review of stated preference studies examining the extent to which cycle infrastructure preferences vary by gender and by age. A search of online, English-language academic and policy literature was followed by a three-stage screening process to identify relevant studies. We found 54 studies that investigated whether preferences for cycle infrastructure varied by gender and/or by age. Forty-four of these studies considered the extent of separation from motor traffic. The remainder of the studies covered diverse topics, including preferred winter maintenance methods and attitudes to cycle track lighting. We found that women reported stronger preferences than men for greater separation from motor traffic. There was weaker evidence of stronger preferences among older people. Differences in preferences were quantitative rather than qualitative; that is, preferences for separated infrastructure were stronger in some groups than in others, but no group preferred integration with motor traffic. Thus, in low-cycling countries seeking to increase cycling, this evidence suggests focusing on the stronger preferences of under-represented groups as a necessary element of universal design for cycling.

Social Influence and Different Types of Red-Light Behaviors among Cyclists

Accident analysis and studies on traffic revealed that cyclists’ violation of red-light regulation is one typical infringement committed by cyclists. Furthermore, an association between cyclists’ crash involvement and red-light violations has been found across different countries. The literature on cyclists’ psychosocial determinants of red-light violation is still scarce. The present study, based on the classification of cyclists’ red-light behavior in risk-taking (ignoring the red-light and traveling through the junction without stopping), opportunistic (waiting at red-lights but being too impatient to wait for green signal and subsequently crossing the junction), and law-obeying (stopping to obey the red-light), adopted an eye-observational methodology to investigate differences in cyclists’ crossing behavior at intersections, in relation to traffic light violations and the presence of other cyclists. Based on the social influence explanatory framework, which states that people tend to behave differently in a given situation taking into consideration similar people’s behaviors, and that the effect of social influence is related to the group size, we hypothesized that the number of cyclists at the intersection will have an influence on the cyclists’ behavior. Furthermore, cyclists will be more likely to violate in an opportunistic way when other cyclists are already committing a violation. Two researchers at a time registered unobtrusively at four different intersections during morning and late afternoon peak hour traffic, 1381 cyclists approaching the traffic light during the red phase. The 62.9% violated the traffic control. Results showed that a higher number of cyclists waiting at the intersection is associated with fewer risk-taking violations. Nevertheless, the percentage of opportunistic violation remained high. For the condition of no cyclist present, risk-taking behaviors were significantly higher, whereas, they were significantly lower for conditions of two to four and five or more cyclists present. The percentage of cyclists committing a red-light violation without following any other was higher for those committing a risk-taking violation, whereas those following tended to commit opportunistic violations more often.

Using mental mapping to unpack perceived cycling risk

Cycling is the most energy-efficient mode of transport and can bring extensive environmental, social and economic benefits. Research has highlighted negative perceptions of safety as a major barrier to the growth of cycling. Understanding these perceptions through the application of novel place-sensitive methodological tools such as mental mapping could inform measures to increase cyclist numbers and consequently improve cyclist safety. Key steps to achieving this include: (a) the design of infrastructure to reduce actual risks and (b) targeted work on improving safety perceptions among current and future cyclists. This study combines mental mapping, a stated-preference survey and a transport infrastructure inventory to unpack perceptions of cycling risk and to reveal both overlaps and discrepancies between perceived and actual characteristics of the physical environment. Participants translate mentally mapped cycle routes onto hard-copy base-maps, colour-coding road sections according to risk, while a transport infrastructure inventory captures the objective cycling environment. These qualitative and quantitative data are matched using Geographic Information Systems and exported to statistical analysis software to model the individual and (infra)structural determinants of perceived cycling risk. This method was applied to cycling conditions in Galway City (Ireland). Participants' (n=104) mental maps delivered data-rich perceived safety observations (n=484) and initial comparison with locations of cycling collisions suggests some alignment between perception and reality, particularly relating to danger at roundabouts. Attributing individual and (infra)structural characteristics to each observation, a Generalised Linear Mixed Model statistical analysis identified segregated infrastructure, road width, the number of vehicles as well as gender and cycling experience as significant, and interactions were found between individual and infrastructural variables. The paper concludes that mental mapping is a highly useful tool for assessing perceptions of cycling risk with a strong visual aspect and significant potential for public participation. This distinguishes it from more traditional cycling safety assessment tools that focus solely on the technical assessment of cycling infrastructure. Further development of online mapping tools is recommended as part of bicycle suitability measures to engage cyclists and the general public and to inform 'soft' and 'hard' cycling policy responses.

Potential risk and its influencing factors for separated bicycle paths

In this paper, we propose two potential risk indicators to define and evaluate the safety of bicycle path at the microscopic level. Field bicycle data were collected from three survey sites under different traffic conditions. These two risk indicators based on speed dispersion were proposed and calculated during each 5-min interval. The risk influences of various widths of bicycle path and traffic conditions were analyzed by using one-way ANOVA. We further proposed a generalized linear model (GLM) for modeling and analyzing the relationships between bicycle risks and v/c ratio and percentages of electric bicycles, male cyclists, young cyclists, and loaded cyclists. The stepwise regression models were applied for determination of coefficients. The results show that the influences of gender and age of cyclists on potential risks are not significant. The risks increase with the width of bicycle path and percentage of electric bicycles, while only for wider bicycle path (4-lane case in this study), the risks are associated with whether or not cyclists are loaded. The findings could contribute for analysis and evaluation of the safety for bicycle path.

Trends in local newspaper reporting of London cyclist fatalities 1992-2012: the role of the media in shaping the systems dynamics of cycling

BACKGROUND

Successfully increasing cycling across a broad range of the population would confer important health benefits, but many potential cyclists are deterred by fears about traffic danger. Media coverage of road traffic crashes may reinforce this perception. As part of a wider effort to model the system dynamics of urban cycling, in this paper we examined how media coverage of cyclist fatalities in London changed across a period when the prevalence of cycling doubled. We compared this with changes in the coverage of motorcyclist fatalities as a control group.

METHODS

Police records of traffic crashes (STATS19) were used to identify all cyclist and motorcyclist fatalities in London between 1992 and 2012. We searched electronic archives of London's largest local newspaper to identify relevant articles (January 1992-April 2014), and sought to identify which police-reported fatalities received any media coverage. We repeated this in three smaller English cities.

RESULTS

Across the period when cycling trips doubled in London, the proportion of fatalities covered in the local media increased from 6% in 1992-1994 to 75% in 2010-2012. By contrast, the coverage of motorcyclist fatalities remained low (4% in 1992-1994 versus 5% in 2010-2012; p=0.007 for interaction between mode and time period). Comparisons with other English cities suggested that the changes observed in London might not occur in smaller cities with lower absolute numbers of crashes, as in these settings fatalities are almost always covered regardless of mode share (79-100% coverage for both cyclist and motorcyclist fatalities).

CONCLUSION

In large cities, an increase in the popularity (and therefore 'newsworthiness') of cycling may increase the propensity of the media to cover cyclist fatalities. This has the potential to give the public the impression that cycling has become more dangerous, and thereby initiate a negative feedback loop that dampens down further increases in cycling. Understanding these complex roles of the media in shaping cycling trends may help identify effective policy levers to achieve sustained growth in cycling.

Investigating traffic light violations by cyclists in Dublin City Centre

This research examines the behaviour of cyclists in Dublin City with specific regard to red light running. A number of specific research questions are raised by this study. These questions address the impact of different infrastructure types on red light running, as well as the behavioural patterns and demographics of offending cyclists. Two data collection methods were used to gather information on cyclists in Dublin City - an observational survey and an online questionnaire. The observational surveys examined cyclist compliance with different traffic signal systems and the impact of on-road and off-road cycle infrastructure. An online questionnaire was used to get direct feedback from cyclists in Dublin City on the reasons (if any) they decide to commit infringement at traffic lights. With the recent growth of cycling in Dublin City (as well as many other international cities) it is vital to accommodate and manage this growing demand by ensuring the safety and road discipline of cyclists. The next few years will be crucial for the continued development of cycling in Dublin, particularly due to the increasing investment by transport planners in cycle infrastructure. It is therefore important to identify now the main factors which influence cyclist's decisions to break red lights in order to guide local traffic authorities in their efforts to reduce such transgressions.

Evaluating the effectiveness of on-street bicycle lane and assessing risk to bicyclists in Charlotte, North Carolina

The objectives of this manuscript are (1) to evaluate the effectiveness of on-street bicycle lane in reducing crashes involving bicyclists on urban roads, (2) to quantify and compare risk to bicyclists on road segments with and without on-street bicycle lane, (3) to evaluate the effect of on-street bicycle lane on other road network users (all crashes), and, (4) to assess the role of on-network characteristics (speed limit, the number of lanes, the width of on-street bicycle lane, the width of the right-most travel lane, and, the numbers of driveways, unsignalized approaches and signalized intersections per unit distance) on risk to bicyclists. Data for thirty-six segments with on-street bicycle lane and twenty-six segments without on-street bicycle lane in the city of Charlotte, North Carolina were extracted to compute and compare measures such as the number of bicycle crashes per center-lane mile, the number of bicycle crashes per annual million vehicle miles traveled (MVMT), the number of all crashes per center-lane mile, and the number of all crashes per MVMT. The results obtained from analysis indicate that bicyclists are three to four times at higher risk (based on traffic conditions) on segments without on-street bicycle lane than when compared to segments with on-street bicycle lane. An analysis conducted considering all crashes showed that on-street bicycle lanes do not have a statistically significant negative effect on overall safety. An increase in annual MVMT (exposure) and the number of signalized intersections per mile increases the number of bicycle crashes, while an increase in on-street bicycle lane width or right-most travel lane width (if on-street bicycle lane cannot be provided) decreases the number of bicycle crashes. Installing wider on-street bicycle lanes, limiting driveways to less than 50 per mile and unsignalized approaches to less than 10 per mile, increasing spacing between signalized intersections, and, facilitating wider right-most travel lane if on-street bicycle lane cannot be provided reduces occurrence of bicycle crashes and lowers risk to bicyclists on roads.

A Spatial Analysis of Land Use and Network Effects on Frequency and Severity of Cyclist-Motorist Crashes in the Copenhagen Region

OBJECTIVE

Urban and transport planners worldwide have recently designed and implemented policies for increasing the number of cyclists. Although cycling is on the rise even in car-oriented cities and regions, the fear of being involved in a crash is still the main obstacle to further increases in cycling market shares. The current study proposes the first joint model of frequency and severity of cyclist-motorist collisions with the aim of unraveling the factors contributing to both the probability of being involved in a crash and, conditional on the crash occurrence, experiencing a severe injury outcome.

METHOD

A multivariate Poisson-lognormal model with correlated autoregressive priors was estimated on a sample of 5,349 cyclist-motorist crashes that occurred in the Copenhagen region between 2009 and 2013. The model considered the links of the road network in the region as the unit of observation, controlled for traffic exposure of nonmotorized and motorized transport modes, evaluated the effect of infrastructure and land use, and accounted for heterogeneity and spatial correlation across links.

RESULTS

Results confirmed the existence of the phenomenon of safety in numbers and added to the narrative by emphasizing that the most severe crashes are the ones most benefiting from an increase in the number of cyclists. In addition, results argued that the construction of Copenhagen-style bicycle paths would significantly contribute to increasing safety, especially in suburban areas where the speed differential between cyclists and motorists is greater. Last, results illustrated a need for thinking about cycling safety in intersection design and reflecting on the importance of spatial and aspatial correlation both within and between injury categories.

CONCLUSIONS

The findings from this study illustrated how encouraging cycling would increase safety in relation to the phenomenon of safety in numbers and how, in turn, increasing safety would convince more people to cycle. In addition, they suggested how the design of bicycle infrastructure should not only consider bicycle lanes but in particular focus on bicycle paths where the number of conflicts and the stress for sharing the road are highly reduced and how thinking about road design should extend to the general level and include a discourse about safer intersections. Last, attention should be given to the road design in the city center and to traffic management, because clearly safer traffic implies more cyclists and, in turn, more cyclists imply fewer cars and less congestion.

A hazard-based duration model for analyzing crossing behavior of cyclists and electric bike riders at signalized intersections

This paper presents a hazard-based duration approach to investigate riders' waiting times, violation hazards, associated risk factors, and their differences between cyclists and electric bike riders at signalized intersections. A total of 2322 two-wheeled riders approaching the intersections during red light periods were observed in Beijing, China. The data were classified into censored and uncensored data to distinguish between safe crossing and red-light running behavior. The results indicated that the red-light crossing behavior of most riders was dependent on waiting time. They were inclined to terminate waiting behavior and run against the traffic light with the increase of waiting duration. Over half of the observed riders cannot endure 49s or longer. 25% of the riders can endure 97s or longer. Rider type, gender, waiting position, conformity tendency and crossing traffic volume were identified to have significant effects on riders' waiting times and violation hazards. Electric bike riders were found to be more sensitive to the external risk factors such as other riders' crossing behavior and crossing traffic volume than cyclists. Moreover, unobserved heterogeneity was examined in the proposed models. The finding of this paper can explain when and why cyclists and electric bike riders run against the red light at intersections. The results of this paper are useful for traffic design and management agencies to implement strategies to enhance the safety of riders.

Reconsidering the safety in numbers effect for vulnerable road users: an application of agent-based modeling

OBJECTIVE

Increasing levels of active transport provide benefits in relation to chronic disease and emissions reduction but may be associated with an increased risk of road trauma. The safety in numbers (SiN) effect is often regarded as a solution to this issue; however, the mechanisms underlying its influence are largely unknown. We aimed to (1) replicate the SiN effect within a simple, simulated environment and (2) vary bicycle density within the environment to better understand the circumstances under which SiN applies.

METHODS

Using an agent-based modeling approach, we constructed a virtual transport system that increased the number of bicycles from 9% to 35% of total vehicles over a period of 1,000 time units while holding the number of cars in the system constant. We then repeated this experiment under conditions of progressively decreasing bicycle density.

RESULTS

We demonstrated that the SiN effect can be reproduced in a virtual environment, closely approximating the exponential relationships between cycling numbers and the relative risk of collision as shown in observational studies. The association, however, was highly contingent upon bicycle density. The relative risk of collisions between cars and bicycles with increasing bicycle numbers showed an association that is progressively linear at decreasing levels of density.

CONCLUSIONS

Agent-based modeling may provide a useful tool for understanding the mechanisms underpinning the relationships previously observed between volume and risk under the assumptions of SiN. The SiN effect may apply only under circumstances in which bicycle density also increases over time. Additional mechanisms underpinning the SiN effect, independent of behavioral adjustment by drivers, are explored.

Aggravating and mitigating factors associated with cyclist injury severity in Denmark

INTRODUCTION

Denmark is one of the leading cycling nations, where cycling trips constitute a large share of the total trips, and cycling safety assumes a top priority position in the agenda of policy makers. The current study sheds light on the aggravating and mitigating factors associated with cyclist injury severity on Danish roads by examining a comprehensive set of accidents involving a cyclist and a collision partner between 2007 and 2011.

METHOD

This study estimates a generalized ordered logit model of the severity of cyclist injuries because of its ability to accommodate the ordered-response nature of severity while relaxing the proportional odds assumption.

RESULTS

Model estimates show that cyclist fragility (children under 10 years old and elderly cyclists over 60 years of age) and cyclist intoxication are aggravating individual factors, while helmet use is a mitigating factor. Speed limits above 70-80 km/h, slippery road surface, and location of the crash on road sections are aggravating infrastructure factors, while the availability of cycling paths and dense urban development are mitigating factors. Heavy vehicle involvement and conflicts between cyclists going straight or turning left and other vehicles going straight are aggravating vehicle involvement factors. Practical applications: The results are discussed in the context of applied policies, engineering, and traffic management solutions for bicycle safety in Denmark.

Dominant role of drivers' attitude in prevention of road traffic crashes: a study on knowledge, attitude, and practice of drivers in Iran

OBJECTIVE

Evaluating the relation between Iranian drivers' knowledge, attitude, and practice (KAP) regarding traffic regulations, and their deterministic effect on road traffic crashes (RTCs).

SETTING

Two cities of Tehran and Zahedan, Iran.

METHODS

A cross-sectional study was designed. Using a simplified cluster sampling design, 2200 motor vehicle drivers including 1200 in Tehran and 1000 in Zahedan were selected. Sixty locations in Tehran and 50 in Zahedan were chosen. In each pre-identified location, 20 adult drivers were approached consecutively. A questionnaire developed by researchers was filled by each participant. The questionnaire had four sections including items assessing the demographics, knowledge, attitude and practice of drivers toward traffic regulations. Logistic regression analysis was used to evaluate the relationship between the RTCs and KAP variables.

RESULTS

The study sample consisted of 619 (28.1%) occupational and 1580 (71.8%) private drivers. Among them, 86.4% were male. The median age was 33.6 ± 10.83. Drivers in Tehran and Zahedan had no significant differences between their mean scores of KAP items of the questionnaire. Higher knowledge, safer attitude, and safer practice were associated with a decreased number of RTC. After adjusting for possible confounders, increase of one standard deviation in attitude and practice scores (but not knowledge) resulted in 26.4% and 18.5% decrease in RTC, respectively. Finally, considering knowledge, attitude and practice of drivers in one model to assess their mutual effect, it was shown that only attitude is significantly associated with a decrease of RTC (OR=0.76, P=0.007).

CONCLUSION

Increase in attitude and practice accompanied with decreased number of RTCs in Iranian drivers. Specifically, drivers' attitude had the crucial effect. It is not knowledge and standard traffic education; rather it is how such education is registered as an attitude that translates what is being learned into actions. Without safer attitude, even safer self-reported practice will not result in lower RTCs.