A prospective cohort study on minor accidents involving commuter cyclists in Belgium

Cyclist's travel distances and risk of falls in snowy and icy conditions in German cities

INTRODUCTION

So far, no studies are known that estimate distance-based risks for cyclist falls in snowy/icy conditions compared to other conditions to account for differences in cycling levels in the different weather situations.

METHOD

The number of cyclist falls was gathered from retrospective surveys in Germany. Cycling distances were obtained from the German Household Travel Survey "Mobility in cities - SrV," assigned to meteorological data, and validated against counts and own surveys. The number of falls per distance cycled and Risk Ratios for snowy/icy versus other weather conditions were estimated.

RESULTS

An average decrease of 53% in the distance travelled per person and day is estimated for snowy/icy days versus other days. This decrease is lower in regions with higher general cycling mode shares. We find average risks of falls from 9.5 to 16 (field surveys) up to 76.5 falls per 10,000 km (online survey) and average Risk Ratios for cycling in snowy/icy conditions of 20 (field survey conducted in times of other weather) to 36 (field survey conducted in times of snow/ice) and 38 (online survey conducted in times of snow/ice). The risk of suffering an injury in the event of a fall is lower in snowy/icy compared to other weather conditions.

CONCLUSIONS

Seeing the current trend of growing general cycling levels in Germany, we expect more cycling in winter and, in case of unchanged winter weather and maintenance, a substantial increase of cyclist falls. The reduced risk of being injured in the event of a fall in snowy/icy conditions does not outweigh the higher risk of falling in the first place.

PRACTICAL APPLICATIONS

Improved winter maintenance on cycling facilities can help increase winter cycling and reduce the risk of falls at the same time.

Circumstances and outcome of active transportation injuries: protocol of a British Columbian inception cohort study

INTRODUCTION

Active transport (AT) is promoted by urban planners and health officials for its environmental, economic and societal benefits and its uptake is increasing. Unfortunately, AT users can be injured or killed due to falls or collisions. Active transport injury (ATI) prevention efforts are hindered by limited research on the circumstances, associated infrastructure, injury pattern, severity and outcome of ATI events. This study seeks to address these knowledge gaps by identifying built environment features associated with injury and risk factors for a poor outcome following ATI.

METHODS AND ANALYSIS

This prospective observational study will recruit an inception cohort of 2000 ATI survivors, including pedestrians, cyclists and micromobility users aged 16 years and older who arrive at a participating emergency department within 48 hours of sustaining an ATI. Baseline interviews capture demographic and socioeconomic information, pre-injury health and functional status, as well as circumstances of the injury event and recovery expectations. Follow-up interviews at 2, 4, 6 and 12 months postinjury (key stages of recovery) use standardised health-related quality of life tools to determine physical and mental health outcomes, functional recovery and healthcare resource use and lost productivity costs.

ETHICS AND DISSEMINATION

The Active Transportation Injury Circumstances and Outcome Study is approved by our institutional research ethics board and the research ethics boards of all participating sites. This study aims to provide healthcare providers with knowledge of risk factors for poor outcome following ATI with the goal of improving patient management. Additionally, this study will provide insight into the circumstances of ATI events including built environment features and how those circumstances relate to recovery outcomes. This information can be used to inform city engineers and planners, policymakers and public health officials to plan roadway design and injury prevention policy.

An Air-Filled Bicycle Helmet for Mitigating Traumatic Brain Injury

We created a novel air-filled bicycle helmet. The aims of this study were (i) to assess the head injury mitigation performance of the proposed helmet and (ii) to compare those performance results against the performance results of an expanded polystyrene (EPS) traditional bicycle helmet. Two bicycle helmet types were subjected to impacts in guided vertical drop tests onto a flat anvil: EPS helmets and air-filled helmets (Bumpair). The maximum acceleration value recorded during the test on the Bumpair helmet was 86.76 ± 3.06 g, while the acceleration during the first shock on the traditional helmets reached 207.85 ± 5.55 g (p < 0.001). For the traditional helmets, the acceleration increased steadily over the number of shocks. There was a strong correlation between the number of impacts and the response of the traditional helmet (cor = 0.94; p < 0.001), while the Bumpair helmets showed a less significant dependence over time (cor = 0.36; p = 0.048), meaning previous impacts had a lower consequence. The air-filled helmet significantly reduced the maximal linear acceleration when compared to an EPS traditional helmet, showing improvements in impact energy mitigation, as well as in resistance to repeated impacts. This novel helmet concept could improve head injury mitigation in cyclists.

Systematic literature review of 10 years of cyclist safety research

Cyclist safety is a research field that is gaining increasing interest and attention, but still offers questions and challenges open to the scientific community. The aim of this study was to provide an exhaustive review of scientific publications in the cyclist safety field. For this purpose, Bibliometrix-R tool was used to analyse 1066 documents retrieved from Web of Science (WoS) between 2012 and 2021. The study examined published sources and productive scholars by exposing their most influential contributions, presented institutions and countries most contributing to cyclist safety and explored countries open towards international collaborations. A keywords analysis provided the most frequent author keywords in cyclist safety shown in a word cloud with E-bike, behaviour, and crash severity representing the primary keywords. Furthermore, a thematic map of cyclist safety field drafted from the author's keywords was identified. The strategic diagram is divided in four quadrants and, according to both density and centrality, the themes can be classified as follows: 1) motor themes, characterized by high value of both centrality and density; 2) niche themes, defined by high density and low centrality; 3) emerging or declining themes, featured by low value of both centrality and density; and 4) basic themes, distinguished by high centrality and low density. The motor themes (i.e., the main topics in cyclist safety field) crash severity and bike network were further explored. The research findings will be useful to develop strategies for making bike a safer and more confident form of transport as well as to guide researchers towards the future scientific knowledge.

Electric scooter accidents leading to emergency department visits: influence of alcohol and outcomes in Stockholm, Sweden

Electric scooters are a popular form of transportation, but accidents have increased with increased usage over the last years with rising health care costs as a consequence. This study aims to quantify accidents associated with the use of alcohol and to compare injuries at the emergency department (ED) among patients who have been involved in an accident involving an electric scooter. We used data from a multi-center retrospective registry-based cohort in the Swedish Traffic Accident Data Acquisition. We included all patients that had been involved in an electric scooter accident needing a visit to all EDs in Stockholm, Sweden during 2019-2020. Data on alcohol intake was manually drawn from medical files. Out of all of the 369 patients, the majority were men (n = 223, 60%) and aged below 30 years (n = 181, 49%). In all, 102 (28%) of the patients had a positive history of alcohol intake prior to the accident. Patients with alcohol intake more often arrived nighttime than those without alcohol, via ambulance (40% and 24%, respectively, p-value < 0.01). Those with alcohol intake needed to be admitted to hospital from the ED instead of being discharged more often than those withour alcohol (17% and 9%, respectively, p-value < 0.05) even if the majority still had minor injuries. Every 33,000 trips on electric scooters are statistically accompanied by an accident leading to an ED visit. We conclude that accidents with electric scooters are often associated with alcohol intake. They often demand more resources, such as an ambulance transfer and admission to hospital, and involve multiple injuries, compared to those without alcohol intake.

Odds of self-reported minor cycle crashes with conventional and electric assisted cycles adjusted for cycling frequency in Dutch and Belgian adults a retrospective study

BACKGROUND

Cycling for transportation and recreation is gaining in popularity, especially in older age groups. The rise in electric assisted cycles (EAC) may also have a role to play in this. With an increase in the number of cyclists comes an increase in the prevalence of cycle crashes. However, there is a lack of knowledge on EAC crashes and crash studies including cycle use data. An important question is also whether the high number of serious road injuries among older cyclists, is due to increased risk or more serious consequences in the event of a crash.

STUDY AIM

To compare the odds of reporting a cycle crash on a conventional (CC) against electrically assisted cycle (EAC), while controlling for age, gender, BMI, impairments while cycling, cycling frequency and region of residence.

METHODS

A 12-month retrospective cross-sectional survey-based study, including male and female cyclists aged 40+ years, was conducted in Belgium and the Netherlands. Socio-demographics, physical and mental impairments while cycling (such as lower reaction time), crash details and cycling frequency data were collected. Cyclists were grouped into CC, EAC or both (CC + EAC) based on the type of cycle they used during the study period. Logistic regression models were used to calculate the odds of reporting a cycle crash. Main and interaction effects were studied.

RESULTS

1,919 cyclists were included in the data analysis (63.2 ± 11.1 years; 50% women). 319 (17% of the total sample) cyclists reported a crash in the previous 12 months, of which 36% were EAC crashes. Those reporting a crash were significantly younger compared to those not reporting a crash. The following significant main effects were observed: those cycling on an EAC had a higher odds of reporting a cycle crash compared to those cycling on a CC (OR = 1.41, 95% CI = 1.01-1.97); cyclists in the category average and high on mental impairments while cycling had a higher odds of reporting a cycle crash compared to those in the category low (OR = 1.72, 95% CI = 1.23-2.40 and OR = 3.49, 95% CI = 2.51-4.90, respectively); higher cycling frequency is related to higher odds of reporting a cycle crash (OR = 3.25, 95% CI = 2.25-4.90). A significant interaction effect was observed between age category and gender (OR = 1.93, 95% CI = 1.15-3.26). Post-hoc tests revealed that men in the younger age category (40-64 years) had the highest probability (18.95%) of reporting a cycle crash, whereas men in the oldest age category (65+ years) had the lowest probability (9.99%) of reporting a cycle crash. No significant difference between age categories in women was observed.

CONCLUSION

This study indicates that within a cohort of middle aged and older adults living in regions with high to low cycling modal shares, cycle type, mental impairments while cycling, cycling frequency and region of residence play a significant role in the odds of reporting a (minor) cycle crash. Men in the age category 40-64 years have a significantly higher probability of reporting a cycle crash compared to men of 65+ years. Safety campaigns and instructions should pay particular attention to men in the age category 40-64 years and those with a mental impairment while cycling.

Secondary task engagement, risk-taking, and safety-related equipment use in German bicycle and e-scooter riders - An observation

The behavioral safety of e-bike and e-scooter riders is a significant concern in traffic safety. In an observational study in Braunschweig, Germany, 4,514 bicycle and e-scooter riders were observed concerning their used vehicles type, secondary task engagement, use of additional safety equipment, and traffic rule violation. Overall, 13.4% of all riders were engaged in any secondary task, wearing headphones or earphones being the most frequent behavior (6.7%), followed by conversations with other cyclists (3.7%). Banned mobile phone use was low (0.8%). Secondary task engagement was positively correlated with traffic rule violations and at-fault conflicts and negatively with the use of additional safety equipment. Cluster analysis on vehicle types and behaviors revealed five groups of riders, two with relatively high numbers of risky behaviors: young and middle-aged, predominantly male riders of conventional bicycles, and a group of demographically similar users of electric bikes and e-scooters. Campaigns targeted at these specific groups may help reduce risky behaviors.

Injured cyclists with focus on single-bicycle crashes and differences in injury severity in Sweden

While cycling is promoted as a clean, energy-efficient mode of transport generating physical activity, the number of injured cyclists must decrease to achieve traffic safety goals. The extent of the single bicycle crashes (SBCs) and crash causes are rather well studied. This study expands this knowledge by focusing on differences in injury severity. The aim of the study is to investigate the relationship between injury severity and characteristics of the crash and the cyclist with focus on SBCs. Furthermore, injury risk is calculated for different age classes and sexes, as well as for different purposes of the trip. The results are based on injured cyclists in Sweden (N = 105,836) registered in STRADA, 2010-2019, by both the police and accident and emergency departments (A&Es), with a special focus on injury severity reported by the A&Es. Binary logistic regression was applied to analyse how the odds of being severely injured differed for different cyclists and situations. Results from of the National Travel Survey, 2011-2016, were used to study differences in distance travelled with respect to sex, age group and purpose of the trip. Given that the cyclist is injured in an SBC, the results show a higher probability of being severely injured (maximal AIS 3 or more) for cyclists 45 years or older compared to younger cyclists, for males compared to females and for cyclists not wearing a helmet compared to cyclists wearing a helmet. A higher probability for severe injury was also found for crashes occurring during leisure trips compared to work/school trips, crashes occurring during weekdays compared to weekends and crashes at intersections and road stretches compared to pedestrian and cycle paths. Furthermore, the risk of being severely injured in an SBC per km travelled was higher for cyclists aged 45 and older and during a leisure trip.

An in-depth analysis of self-reported cycling injuries in single and multiparty bicycle crashes in Denmark

INTRODUCTION

Cycling is one of the main forms of transportation in Denmark. However, while the number of traffic crash fatalities in the country has decreased over the past decade, the frequency of cyclists killed or seriously injured has increased. The high rate of serious injuries and fatalities associated with cycling emphasizes the increasing need for mitigating the severity of such crashes.

METHOD

This study conducted an in-depth analysis of cyclist injury severity resulting from single and multiparty bicycle-involved crashes. Detailed information was collected using self-reporting data undertaken in Denmark for a 12-month period between 1 November 2012 and 31 October 2013. Separate multilevel logistic (MLL) regression models were applied to estimate cyclist injury severity for single and multiparty crashes. The goodness-of-fit measures favored the MLL models over the standard logistic models, capturing the intercorrelation among bicycle crashes that occurred in the same geographical area.

RESULTS

The results also showed that single bicycle-involved crashes resulted in more serious outcomes when compared to multiparty crashes. For both single and multiparty bicycle crash categories, non-urban areas were associated with more serious injury outcomes. For the single crashes, wet surface condition, autumn and summer seasons, evening and night periods, non-adverse weather conditions, cyclists aged between 45 and 64 years, male sex, riding for the purpose of work or educational activities, and bicycles with light turned-off were associated with severe injuries. For the multiparty crashes, intersections, bicycle paths, non-winter season, not being employed or retired, lower personal car ownership, and race bicycles were directly related to severe injury consequences. Practical Applications: The findings of this study demonstrated that the best way to promote cycling safety is the combination of improving the design and maintenance of cycling facilities, encouraging safe cycling behavior, and intensifying enforcement efforts.

An overview of tram tracks related cycling injuries in Ghent, Belgium

OBJECTIVE

There is a paucity of data on the incidence and severity of tram tracks related cycling injuries. The aim of this study is to get insight into the incidence, severity and characteristics of tram tracks related cycling injuries, potentially defining significant 'hotspots' in the Ghent city area.

METHODS

A one-year, multicenter, prospective, observational study was conducted. Patients presenting to the emergency departments of all 4 Ghent hospitals with tram tracks related cycling injury, were included. Data on patient demographics, circumstances of the accident and type of injury were collected.

RESULTS

149 patients were included, with a median age of 31 years. 42 patients had fractures, 39 patients required wound sutures, 79 and 49 patients suffered from bruising and abrasions respectively. Only 5 patients required admission. No patients died or suffered life-threatening injuries. Women (65.1%) presented more frequently than men (34.9%). Forty-tree percent of all accidents happened in autumn (p < 0.001). Accidents happened more frequently in rainy conditions (p < 0.001). Mean number of days off work was 2.7 days, significantly increasing to 6.56 days when sustaining a fracture or dislocation (p = 0.02).

CONCLUSION

Tram tracks are potentially dangerous and may lead to clinically important injuries and significant number of days off work.

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.

Are Latin American cycling commuters "at risk"? A comparative study on cycling patterns, behaviors, and crashes with non-commuter cyclists

INTRODUCTION

As part of the transformation of urban transportation dynamics, commuter cycling has acquired a high relevance as an alternative mode of transport in different countries, and Latin America seems to be one of the main focus of this worldwide "revolution". However, the high rates of crashes and injuries suffered by commuters have become a relevant issue in the field of road safety, especially in emerging regions with low cycling tradition, where social and infrastructural gaps may endanger the cyclists' safety.

OBJECTIVES

This study had two objectives. First, to compare key safe cycling-related variables between cycling commuters and non-commuters; and second, to differentially asses the effect of individual and cycling-related variables on their self-reported crash rates.

METHOD

For this cross-sectional research, the data provided by 577 Latin American urban cyclists from three countries (Argentina, Colombia and Mexico) with a mean age of 32.7 years was used. They answered a questionnaire on cycling habits, risk perception, rule knowledge, cycling behaviors and riding crashes.

RESULTS

The outcomes of this study showed that, despite having a higher risk perception, cycling commuters perform deliberate risky cycling behaviors (traffic violations) more frequently, and they suffer more crashes; cycling commuters report higher rates of psychological distress, and a lower degree of rule knowledge and protective behaviors than non-commuters. Furthermore, structural similarities and differences in the explanation of cycling crashes were found across commuters and non-commuters.

CONCLUSION

The results of this study suggest that non-commuters, whose purposes for cycling are more aimed at leisure and occasional trips, perform less risky behaviors but suffer more cycling distractions, whereas commuters are comparatively more exposed to behavioral-based safety risks, and suffer more frequent crashes. Since recent evidence forecasts that urban cycling will keep growing in Latin American cities, it is necessary to implement policies and educational/training improvements that may enhance the safety and health of cyclists in these countries.

Factors influencing the injury severity of single-bicycle crashes

The majority of research on bicyclist injury severity relates to bicycle-motor vehicle crashes, even though single-bicycle crashes make up more than half of bicycle crashes. This study explores the factors related to the injury severity outcome of single-bicycle crashes. We use single-bicycle crash data obtained from medical records collected in the period 2010-2015 combined with road maintenance data. The data includes three injury severity categories: 'severe injury', 'slight injury', 'no injury'. The relation between the factors surrounding single-bicycle crashes and the resulting injury severity is estimated using a latent class ordered probit model. The model estimation identifies three latent classes where the likelihood of cyclist membership depends on the bicyclist's age and gender. Furthermore, several factors appear to affect the likelihood of injuries in single-bicycle crashes. These are the road geometry (i.e. if the crash occurred on a bicycle lane or a road section), maintenance level, and the interaction between road geometry and maintenance level. The findings suggest that single-bicycle crashes on road sections result in more severe injuries than single-bicycle crashes on bicycle lanes. The largest effect is seen when a single-bicycle crash occurs on a road section with a poorly maintained bicycle lane being available. Crashes on low volume roads with few bicyclists are also related to an increased probability of severe injury as well as crashes occurring after dark.

Roles of infrastructure and land use in bicycle crash exposure and frequency: A case study using Greater London bike sharing data

Cycling is increasingly promoted as a sustainable transport mode. However, bicyclists are more vulnerable to fatality and severe injury in road crashes, compared to vehicle occupants. It is necessary to identify the contributory factors to crashes and injuries involving bicyclists. For the prediction of motor vehicle crashes, comprehensive traffic count data, i.e. AADT and vehicle kilometer traveled (VKT), are commonly available to proxy the exposure. However, extensive bicycle count data are usually not available. In this study, revealed bicycle trip data of a public bicycle rental system in the Greater London is used to proxy the bicycle crash exposure. Random parameter negative binomial models are developed to measure the relationship between possible risk factors and bicycle crash frequency at the zonal level, based on the crash data in the Greater London in 2012-2013. Results indicate that model taking the bicycle use time as the exposure measure is superior to the other counterparts with the lowest AIC (Akaike information criterion) and BIC (Bayesian information criterion). Bicycle crash frequency is positively correlated to road density, commercial area, proportion of elderly, male and white race, and median household income. Additionally, separate bicycle crash prediction models are developed for different seasons. Effects of the presence of Cycle Superhighway and proportion of green area on bicycle crash frequency can vary across seasons. Findings of this study are indicative to the development of bicycle infrastructures, traffic management and control, and education and enforcement strategies that can enhance the safety awareness of bicyclists and reduce their crash risk in the long run.

Approaching Bike Hazards via Crowdsourcing of Volunteered Geographic Information

Information on individual hazard perception while cycling and the associated feeling of safety are key aspects to foster sustainable urban cycling mobility. Although cyclist’s perceptions must also be critically reviewed, such crowdsourced Volunteered Geographic Information (VGI) provides wide-ranging insights on diverse hazard categories in cycling. In this case study in the city of Freiburg, Germany, hazard perceptions, information about lane types, and the underlying routes were crowdsourced via an open source smartphone application by a small group with the aim of providing cyclists with effective solutions. By dealing with levels of reliability, we show that even a small group of laypersons can generate an extensive and valuable set of VGI consisting of comprehensive hazard categories. We demonstrate that (1) certain hazards are interlinked to specific lane types, and (2) the individual hazard perceptions and objective parameters, i.e., accident data, are often congruent spatially; consequently, (3) dangerous hot spots can be derived. By considering cyclists’ needs, this approach outlines how a people-based perspective can supplement regional planning on the local scale.

Motor Vehicle Crashes Involving a Bicycle Before and After Introduction of a Bike Share Program in Philadelphia, Pennsylvania, 2010-2018

Objectives. To quantify the impact of a citywide bicycle share program on rates of motor vehicle collisions involving a bicycle.Methods. We conducted an interrupted time series analysis, using crash records from the Pennsylvania Department of Transportation for Philadelphia County from 2010 through 2018. We also calculated summary statistics to illustrate annual and monthly trends in rates of motor vehicle crashes involving a bicycle.Results. The baseline rate of bike events was 106% greater (95% confidence interval [CI] = 1.25, 3.38) at the time bicycle share was implemented compared with January 2010. Before bicycle share implementation, the rate of bicycle events decreased 1% (95% CI = 0.95, 1.03) annually. After the bicycle share program started, the rate of bicycle events decreased 13% (95% CI = 0.82, 0.94) annually.Conclusions. In the long term, programs that increase the number of bicycles on the road, such as bike share, may reduce rates of motor vehicle crashes involving a bicycle.

Cyclist crash rates and risk factors in a prospective cohort in seven European cities

Increased cycling uptake can improve population health, but barriers include real and perceived risks. Crash risk factors are important to understand in order to improve safety and increase cycling uptake. Many studies of cycling crash risk are based on combining diverse sources of crash and exposure data, such as police databases (crashes) and travel surveys (exposure), based on shared geography and time. When conflating crash and exposure data from different sources, the risk factors that can be quantified are only those variables common to both datasets, which tend to be limited to geography (e.g. countries, provinces, municipalities) and a few general road user characteristics (e.g. gender and age strata). The Physical Activity through Sustainable Transport Approaches (PASTA) project was a prospective cohort study that collected both crash and exposure data from seven European cities (Antwerp, Barcelona, London, Örebro, Rome, Vienna and Zürich). The goal of this research was to use data from the PASTA project to quantify exposure-adjusted crash rates and model adjusted crash risk factors, including detailed sociodemographic characteristics, attitudes about transportation, neighbourhood built environment features and location by city. We used negative binomial regression to model the influence of risk factors independent of exposure. Of the 4,180 cyclists, 10.2 % reported 535 crashes. We found that overall crash rates were 6.7 times higher in London, the city with the highest crash rate, relative to Örebro, the city with the lowest rate. Differences in overall crash rates between cities are driven largely by crashes that did not require medical treatment and that involved motor-vehicles. In a parsimonious crash risk model, we found higher crash risks for less frequent cyclists, men, those who perceive cycling to not be well regarded in their neighbourhood, and those who live in areas of very high building density. Longitudinal collection of crash and exposure data can provide important insights into individual differences in crash risk. Substantial differences in crash risks between cities, neighbourhoods and population groups suggest there is great potential for improvement in cycling safety.

Cycling related major trauma in Ireland

INTRODUCTION

Cycling as a means of transport or recreational activity is increasing in popularity in Ireland. However, increasing numbers of cyclists may lead to an increased number of bicycle collisions and fatalities. The Road Safety Authority is the statutory body for road safety in Ireland but uses police data alone to collate cycling collision statistics. This may lead to an underestimation of cycling injuries in Ireland. Using hospital statistics may provide a greater understanding of cycling trauma in Ireland.

OBJECTIVE

The present study examines cycling related trauma in Ireland using the Major Trauma Audit (MTA) data collected via the Trauma and Research Network (TARN) from hospitals in Ireland for the period 2014 to 2016. The database was interrogated for demographics, mechanism of injury, injury characteristics and patient outcomes.

RESULTS

There were 410 cycling collisions recorded in the TARN database which represented 4.4% of trauma captured by TARN for the study period. Of this cohort 79% were male compared with 58% in the overall (TARN) trauma cohort (p < 0.001) and the median (IQR) age was 43.8 years (31.0, 55.7) which is younger than the median (IQR) of 58.9 (36.2, 76.0) years for the overall trauma cohort (p < 0.001). Cycling collisions had a median (IQR) injury severity score (ISS) of 10 (9, 20) which was higher than the overall trauma cohort ISS of 9 (9, 17). Of the mechanisms observed for cycling trauma, 31.7% (n = 130) had a collision with a motor vehicle. Of those who did not wear a helmet, 52.2% (n = 47) sustained a head injury compared with 27.5% (n = 44) in the group who were wearing a helmet (p < 0.001).

CONCLUSION

The TARN data presented in this paper builds a more complete overview of the burden of cycling collisions in Ireland. Particular points of focus are that serious cycling injuries occur in a predominantly male population, and that only around 30% of cases are recorded as involving a motor vehicle, with the majority having an unknown mechanism of injury. There was an association between helmets and head injuries in this study, but there are likely other contributing factors such as mechanism of injury, velocity or cycling infrastructure. Using hospital data such as the MTA provides valuable information on the injuries sustained by cyclists, but more prospective studies to capture injury mechanism and contributing factors are needed.

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.

Personality and Behavioral Predictors of Cyclist Involvement in Crash-Related Conditions

In recent years, the increasing rate of road crashes involving cyclists with a disproportionate overrepresentation in injury statistics has become a major concern in road safety and public health. However, much remains unknown about factors contributing to cyclists’ high crash rates, especially those related to personal characteristics. This study aims to explore the influence of cyclist personality traits and cycling behaviors on their road safety outcomes using a mediated model combining these constructs. A total of 628 cyclists completed an online questionnaire consisting of questions related to cycling anger, impulsiveness, normlessness, sensation seeking, risky cycling behaviors, and involvement in crash-related conditions in the past year. After the psychometric properties of the employed scales were examined, the relationships among the tested constructs were investigated using structural equation modeling. The results showed that cyclists’ crash risks were directly predicted by risky cycling behaviors and cycling anger, and the effects of cycling anger, impulsiveness, as well as normlessness on crash risks, were mediated by cycling behaviors. The current findings provide insight into the importance of personality traits in impacting cycling safety and could facilitate the development of evidence-based prevention and promotion strategies targeting cyclists in China.

Integrating Spatial and Temporal Approaches for Explaining Bicycle Crashes in High-Risk Areas in Antwerp (Belgium)

The majority of bicycle crash studies aim at determining risk factors and estimating crash risks by employing statistics. Accordingly, the goal of this paper is to evaluate bicycle–motor vehicle crashes by using spatial and temporal approaches to statistical data. The spatial approach (a weighted kernel density estimation approach) preliminarily estimates crash risks at the macro level, thereby avoiding the expensive work of collecting traffic counts; meanwhile, the temporal approach (negative binomial regression approach) focuses on crash data that occurred on urban arterials and includes traffic exposure at the micro level. The crash risk and risk factors of arterial roads associated with bicycle facilities and road environments were assessed using a database built from field surveys and five government agencies. This study analysed 4120 geocoded bicycle crashes in the city of Antwerp (CA, Belgium). The data sets covered five years (2014 to 2018), including all bicycle–motorized vehicle (BMV) crashes from police reports. Urban arterials were highlighted as high-risk areas through the spatial approach. This was as expected given that, due to heavy traffic and limited road space, bicycle facilities on arterial roads face many design problems. Through spatial and temporal approaches, the environmental characteristics of bicycle crashes on arterial roads were analysed at the micro level. Finally, this paper provides an insight that can be used by both the geography and transport fields to improve cycling safety on urban arterial roads.

Crash characteristics of on-road single-bicycle crashes: an under-recognised problem

Compared with crashes with motor vehicles, single-bicycle crashes are an under-recognised contributor to cycling injury and the aetiology is poorly understood. Using an in-depth crash investigation technique, this study describes the crash characteristics and patient outcomes of a sample of cyclists admitted to hospital following on-road bicycle crashes. Enrolled cyclists completed a structured interview, and injury details and patient outcomes were extracted from trauma registries. Single-bicycle crashes (n=62) accounted for 48% of on-road crashes and commonly involved experienced cyclists. Common single-bicycle crash types included loss-of-control events, interactions with tram tracks, striking potholes or objects or resulting from mechanical issues with the bicycle. To address single-bicycle crashes, targeted countermeasures are required for each of these specific crash types.

Independent factors associated with bicycle helmet use in a Korean population: A cross-sectional study

OBJECTIVE

Although identification of factors that influence helmet use during bicycle riding is necessary for the selection of groups that require safe cycling education, limited baseline data are available. The aim of the present study was to analyze the rate of helmet use and the demographic factors that were independently associated with helmet use among Korean bicycle riders.

METHODS

In this cross-sectional study, we used public data from the Sixth Korean National Health and Nutrition Examination Survey conducted in 2013 and 2014. Helmet users were defined as subjects who always, usually, or frequently wore helmets when cycling. Independent factors associated with helmet use were determined using odds ratios (ORss) adjusted for 5 demographic factors via multivariate logistic regression analysis.

RESULTS

In the total population, 4,103 individuals were bicycle riders; among these, 782 individuals (19.1%) wore helmets. A total of 21.1% of male riders used helmets, compared to 15.5% of female riders (P <.001). The adjusted logistic regression model revealed that female sex (OR = 0.665; 95% confidence interval [CI], 0.554-0.797), teenage status (OR = 0.475, 95% CI, 0.333-0.678), and low household income (OR = 0.657, 95% CI 0.513-0.841) were significantly associated with nonuse of helmets.

CONCLUSIONS

Female sex, teenage status, and low household income were independent factors associated with the nonuse of helmets. We identified factors associated with helmet use during bicycle riding through analysis of baseline data on helmet usage.

Randomized trials and self-reported accidents as a method to study safety-enhancing measures for cyclists-two case studies

A large number of studies show that high visibility in traffic is important in the struggle of getting the attention from other road users and thus an important safety factor. Cyclists have a much higher risk of being killed or injured in a traffic accident than car drivers so for them high visibility is particularly important. A number of studies have examined the effect of high visibility, such as reflective clothing, but most studies have been primitive, the data limited and the results very uncertain. In this paper we describe the safety impact of increased visibility of cyclists through two randomised controlled trials: permanent running lights on bicycles and a yellow bicycle jacket, respectively. The effect of running lights was studied through a trial where the lights were mounted to 1,845 bicycles and 2,000 others comprised a control group. The bicycle accidents were recorded every two month in a year through self-reporting on the Internet. Participants were asked to report all cycling accidents independently of severity to avoid differences between participants as regards to which accidents were reported. They reported a total of 255 accidents i.e. 7 accidents per 100 cyclists. The results showed that the incidence rate for multiparty bicycle accidents with personal injury was 47% lower for cyclists with permanent running light. The difference is statistically significant at the 5% level. The effect of a yellow bicycle jacket was examined through a trial with 6,800 volunteer cyclists. The half of the group received a bicycle jacket and the other half comprised a control group. Both groups reported every month all their bicycle accidents independently of severity on the Internet. They reported a total of 694 accidents i.e. 10 accidents per 100 cyclists. The treatment group was asked each month if they carried the jacket on their last cycling trip. The results showed that on a random day the treatment group carried the jacket or other fluorescent cycling garment on 77% of their cycle trips. The incidence rate for multiparty accidents with personal injury was 38% lower than the control group. The difference is statistically significant at the 5% level. The trials were not blind and it seems that the lack of blinding has influenced the level of the groups accident reporting. To address this bias we used a correction factor formed by the difference in the number of single accidents of the two groups. The experiences with self-reporting of accidents via a web based questionnaire sent by e-mail with one respective two month intervals were very good; in both trials more than 80% answered all questionnaires whereas less than 2% did not answer, and the quality of the self-reported accident was considered high.

Where do bike lanes work best? A Bayesian spatial model of bicycle lanes and bicycle crashes

US municipalities are increasingly introducing bicycle lanes to promote bicycle use, increase roadway safety and improve public health. The aim of this study was to identify specific locations where bicycle lanes, if created, could most effectively reduce crash rates. Previous research has found that bike lanes reduce crash incidence, but a lack of comprehensive bicycle traffic flow data has limited researchers' ability to assess relationships at high spatial resolution. We used Bayesian conditional autoregressive logit models to relate the odds that a bicycle injury crash occurred on a street segment in Philadelphia, PA (n = 37,673) between 2011 and 2014 to characteristics of the street and adjacent intersections. Statistical models included interaction terms to address the problem of unknown bicycle traffic flows, and found bicycle lanes were associated with reduced crash odds of 48% in streets segments adjacent to 4-exit intersections, of 40% in streets with one- or two-way stop intersections, and of 43% in high traffic volume streets. Presence of bicycle lanes was not associated with change in crash odds at intersections with less or more than 4 exits, at 4-way stop and signalized intersections, on one-way streets and streets with trolley tracks, and on streets with low-moderate traffic volume. The effectiveness of bicycle lanes appears to depend most on the configuration of the adjacent intersections and on the volume of vehicular traffic. Our approach can be used to predict specific street segments on which the greatest absolute reduction in bicycle crash odds could occur by installing new bicycle lanes.

Infrastructural and Human Factors Affecting Safety Outcomes of Cyclists

The increasing number of registered road crashes involving cyclists during the last decade and the high proportion of road crashes resulting in severe injuries and fatalities among cyclists constitutes a global issue for community health, urban development and sustainability. Nowadays, the incidence of many risk factors for road crashes of cyclists remains largely unexplained. Given the importance of this issue, the present study has been conducted with the aim of determining relationships between infrastructural, human factors and safety outcomes of cyclists. Objectives: This study aimed, first, to examine the relationship between key infrastructural and human factors present in cycling, bicycle-user characteristics and their self-reported experience with road crashes. And second, to determine whether a set of key infrastructural and human factors may predict their self-reported road crashes. Methods: For this cross-sectional study, a total of 1064 cyclists (38.8% women, 61.2% men; M = 32.8 years of age) from 20 different countries across Europe, South America and North America, participated in an online survey composed of four sections: demographic data and cycling-related factors, human factors, perceptions on infrastructural factors and road crashes suffered. Results: The results of this study showed significant associations between human factors, infrastructural conditions and self-reported road crashes. Also, a logistic regression model found that self-reported road crashes of cyclists could be predicted through variables such as age, riding intensity, risky behaviours and problematic user/infrastructure interactions. Conclusions: The results of this study suggest that self-reported road crashes of cyclists are influenced by features related to the user and their interaction with infrastructural characteristics of the road.

Under-reporting bicycle accidents to police in the COST TU1101 international survey: Cross-country comparisons and associated factors

Police crash reports are often the main source for official data in many countries. However, with the exception of fatal crashes, crashes are often underreported in a biased manner. Consequently, the countermeasures adopted according to them may be inefficient. In the case of bicycle crashes, this bias is most acute and it probably varies across countries, with some of them being more prone to reporting accidents to police than others. Assessing if this bias occurs and the size of it can be of great importance for evaluating the risks associated with bicycling. This study utilized data collected in the COST TU1101 action "Towards safer bicycling through optimization of bicycle helmets and usage". The data came from an online survey that included questions related to bicyclists' attitudes, behaviour, cycling habits, accidents, and patterns of use of helmets. The survey was filled by 8655 bicyclists from 30 different countries. After applying various exclusion factors, 7015 questionnaires filled by adult cyclists from 17 countries, each with at least 100 valid responses, remained in our sample. The results showed that across all countries, an average of only 10% of all crashes were reported to the police, with a wide range among countries: from a minimum of 0.0% (Israel) and 2.6% (Croatia) to a maximum of a 35.0% (Germany). Some factors associated with the reporting levels were type of crash, type of vehicle involved, and injury severity. No relation was found between the likelihood of reporting and the cyclist's gender, age, educational level, marital status, being a parent, use of helmet, and type of bicycle. The significant under-reporting - including injury crashes that do not lead to hospitalization - justifies the use of self-report survey data for assessment of bicycling crash patterns as they relate to (1) crash risk issues such as location, infrastructure, cyclists' characteristics, and use of helmet and (2) strategic approaches to bicycle crash prevention and injury reduction.

Crashes involving cyclists aged 50 and over in the Netherlands: An in-depth study

The number of seriously injured cyclists is increasing in the Netherlands. The majority of these seriously injured cyclists were involved in single-bicycle or bicycle-bicycle crashes. Little is known about the circumstances in which these crashes occur, as the police only registers 4% of these crashes. Therefore, an in-depth study was carried out to gain insight into the factors and circumstances that influence the occurrence and consequences of these crashes. The focus was on crashes involving cyclists aged 50 and over, as this group has a large share in the number of cyclist-only crashes. Detailed information on 41 single-bicycle and bicycle-bicycle crashes was collected and analysed. This resulted in a description of the course of events for every analysed crash, including a list of factors that had contributed to the occurrence of the crash and possible injuries. Subsequently, crashes with a similar course of events and a comparable combination of contributory factors were grouped into types of crashes. Results showed that cyclists aged 75 and over are more often involved in falls from a bicycle than younger cyclists. Contributory factors that played a role in a large number of crashes were behaviour of another road user, distraction and narrow cycling facilities or traffic lanes. However, which factors played a role in the occurrence of a crash depended on the type of crash. Eight types of crashes were identified. Based on the factors that played a role in the occurrence of these crashes, remedial measures can be developed to prevent similar crashes from occurring in the future.

Reading cyclist intentions: Can a lead cyclist's behaviour be predicted?

As a cyclist, it is essential to make inferences about the intentions of other road users in order to anticipate their behaviour. There are official ways for cyclists to communicate their intentions to other road users, such as using their arms to point in the intended direction of travel. However, in everyday traffic cyclists often do not use such active forms of communication. Therefore, other visual cues have to be used to anticipate (critical) encounters or events. During this study, 108 participants completed a video internet survey in which they predicted the intentions of a lead cyclist based on visible behaviour preceding a turning manoeuvre. When the lead cyclist approached the intersection, each video was stopped just before the cyclist initiated turning. Based on visual cues, the participants had to select which direction they thought the cyclist would go. After entering their prediction, they were asked how certain they were about their prediction and on which visible behaviour(s) each prediction was based. The results show that it is very hard to predict the direction of a turning cyclist based on visual cues before the turning manoeuvre is initiated. Exploratory regression analyses revealed that observable behaviours such as head movements and cycling speed were related to prediction accuracy. These results may be used to support cyclists in traffic interactions.

Multiuse trail intersection safety analysis: A crowdsourced data perspective

Real and perceived concerns about cycling safety are a barrier to increased ridership in many cities. Many people prefer to bike on facilities separated from motor vehicles, such as multiuse trails. However, due to underreporting, cities lack data on bike collisions, especially along greenways and multiuse paths. We used a crowdsourced cycling incident dataset (2005-2016) from BikeMaps.org for the Capital Regional District (CRD), BC, Canada. Our goal was to identify design characteristics associated with unsafe intersections between multiuse trails and roads. 92.8% of mapped incidents occurred between 2014 and 2016. We extracted both collision and near miss incidents at intersections from BikeMaps.org. We conducted site observations at 32 intersections where a major multiuse trail intersected with roads. We compared attributes of reported incidents at multiuse trail-road intersections to those at road-road intersections. We then used negative binomial regression to model the relationship between the number of incidents and the infrastructure characteristics at multiuse trail-road intersections. We found a higher proportion of collisions (38%, or 17/45 total reports) at multiuse trail-road intersections compared to road-road intersections (23%, or 62/268 total reports). A higher proportion of incidents resulted in an injury at multiuse trail-road intersections compared to road-road intersections (33% versus 15%). Cycling volumes, vehicle volumes, and trail sight distance were all associated with incident frequency at multiuse trail-road intersections. Supplementing traditional crash records with crowdsourced cycling incident data provides valuable evidence on cycling safety at intersections between multiuse trails and roads, and more generally, when conflicts occur between diverse transportation modes.

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.

Characteristics of cyclist crashes in Italy using latent class analysis and association rule mining

The factors associated with severity of the bicycle crashes may differ across different bicycle crash patterns. Therefore, it is important to identify distinct bicycle crash patterns with homogeneous attributes. The current study aimed at identifying subgroups of bicycle crashes in Italy and analyzing separately the different bicycle crash types. The present study focused on bicycle crashes that occurred in Italy during the period between 2011 and 2013. We analyzed categorical indicators corresponding to the characteristics of infrastructure (road type, road signage, and location type), road user (i.e., opponent vehicle and cyclist's maneuver, type of collision, age and gender of the cyclist), vehicle (type of opponent vehicle), and the environmental and time period variables (time of the day, day of the week, season, pavement condition, and weather). To identify homogenous subgroups of bicycle crashes, we used latent class analysis. Using latent class analysis, the bicycle crash data set was segmented into 19 classes, which represents 19 different bicycle crash types. Logistic regression analysis was used to identify the association between class membership and severity of the bicycle crashes. Finally, association rules were conducted for each of the latent classes to uncover the factors associated with an increased likelihood of severity. Association rules highlighted different crash characteristics associated with an increased likelihood of severity for each of the 19 bicycle crash types.

Road accidents involving bicycles: configurations and injuries

This study analyzed the most common types of accident involving bicycles and compared the frequency of injuries. The data source was the database of German In-Depth Accident Study (GIDAS). Cases consist of bicycles and their riders involved in accidents between 2000 and 2010. In most collisions, the bicycle impacted with a car. The percentage of injured bicyclists was higher in collisions with a heavy vehicle and decreased when the bicycle impacted with lighter vehicles. A high percentage of injured bicyclists in single accidents was observed; the most severe injury was more frequently to head and extremities. Accidents involving a car and a bicycle with the right of way in a bicycle path represented about 20% of involved and injured bicyclists. The ten most frequent configurations represented about 60% of involved and injured bicyclists. These results contribute to understand the dangerous scenarios for bicyclists and to suggest preventive actions.

Characteristics of bicycle crashes in an adolescent population in Flanders (Belgium)

INTRODUCTION

In regions where transportation is mainly motorized, air pollution and traffic congestion are rife. Active transportation such as cycling might be a solution but safety is a major concern. An efficient science based safety policy is needed. The aim of this paper is to analyze in depth the bicycle crash causes and characteristics in an adolescent population (14-18 yr).

METHODS

By using questionnaires for self-reported bicycle crashes, bicycle crash data were collected from insurance companies (January 2014-June 2015) and from schools (November 2013-March 2014). Six bicycle crash causes were predefined and possible differences between schools and insurance companies were analyzed.

RESULTS

Eighty-six school and 78 insurance registered crashes were analyzed. "Distraction of the cyclist" and "third party crossing a bicycle path failing to see the cyclist" are the main causes of bicycle crashes (both 29%). Bad (maintained) infrastructure accounted for 21% of the crash causes. Bicycle crashes reported at insurance companies needed significantly more medical attention and led to high absenteeism (57% at least one day of absenteeism). Only 21% of the bicycle crashes reported at insurance companies were also reported in the official police database.

CONCLUSION

The human factor was the main cause accounting for 79% of the crashes. Bicycle crashes involving a car accounted for 42% and single bicycle crashes accounted for 31% of the total number of crashes. From the bicycle crashes registered at insurance companies 21% was also registered in official police statistics. A combination of information, education and changing the bicycle specific environment might reduce the consequences of human errors more efficiently.

Modeling and Optimization of Airbag Helmets for Preventing Head Injuries in Bicycling

Bicycling is the leading cause of sports-related traumatic brain injury. Most of the current bike helmets are made of expanded polystyrene (EPS) foam and ultimately designed to prevent blunt trauma, e.g., skull fracture. However, these helmets have limited effectiveness in preventing brain injuries. With the availability of high-rate micro-electrical-mechanical systems sensors and high energy density batteries, a new class of helmets, i.e., expandable helmets, can sense an impending collision and expand to protect the head. By allowing softer liner medium and larger helmet sizes, this novel approach in helmet design provides the opportunity to achieve much lower acceleration levels during collision and may reduce the risk of brain injury. In this study, we first develop theoretical frameworks to investigate impact dynamics of current EPS helmets and airbag helmets-as a form of expandable helmet design. We compared our theoretical models with anthropomorphic test dummy drop test experiments. Peak accelerations obtained from these experiments with airbag helmets achieve up to an 8-fold reduction in the risk of concussion compared to standard EPS helmets. Furthermore, we construct an optimization framework for airbag helmets to minimize concussion and severe head injury risks at different impact velocities, while avoiding excessive deformation and bottoming-out. An optimized airbag helmet with 0.12 m thickness at 72 ± 8 kPa reduces the head injury criterion (HIC) value to 190 ± 25 at 6.2 m/s head impact velocity compared to a HIC of 1300 with a standard EPS helmet. Based on a correlation with previously reported HIC values in the literature, this airbag helmet design substantially reduces the risks of severe head injury up to 9 m/s.

Impaired quality of life after bicycle trauma

INTRODUCTION

Bicycle crashes often affect individuals in working age, and can impair quality of life (QoL) as a consequence. The aim of this study was to investigate QoL in bicycle trauma patients and to identify those at risk of impaired QoL.

PATIENTS AND METHODS

173 bicycle trauma patients who attended a level I trauma centre from 2010 to 2012 received Hadorn's QoL questionnaire six months after their crash. Medical data was collected from the patient's records. Univariate ordinal logistic regression was used to investigate the association between QoL and other factors.

RESULTS

148 patients returned the questionnaire (85.5%). The majority had only mild or minor injuries (85.1%; n=126). However, 72.1% (n=106) still suffered from pain or other physical symptoms more than six months after their bicycle crash. Patients with a Glasgow Coma Scale (GCS) ≤13 or an Injury Severity Score (ISS) >15 experienced impaired emotions/outlook on life (p-values 0.003 and 0.045, respectively). Physical suffering was reported by patients with a GCS ≤13 and in those with injuries to the cervical spine (p-values 0.02 and 0.025, respectively). Patients with an ISS >15 or facial fractures experienced limitations in daily activities (p-values 0.031 and 0.025, respectively).

CONCLUSIONS

More than 70% of bicycle trauma patients suffered physically more than six months after their crash, even though only 15% were severely injured. Risk factors for an impaired QoL were cervical spine injuries or facial fractures, a GCS ≤13 and an ISS >15.

Physical Activity through Sustainable Transport Approaches (PASTA): a study protocol for a multicentre project

INTRODUCTION

Only one-third of the European population meets the minimum recommended levels of physical activity (PA). Physical inactivity is a major risk factor for non-communicable diseases. Walking and cycling for transport (active mobility, AM) are well suited to provide regular PA. The European research project Physical Activity through Sustainable Transport Approaches (PASTA) pursues the following aims: (1) to investigate correlates and interrelations of AM, PA, air pollution and crash risk; (2) to evaluate the effectiveness of selected interventions to promote AM; (3) to improve health impact assessment (HIA) of AM; (4) to foster the exchange between the disciplines of public health and transport planning, and between research and practice.

METHODS AND ANALYSIS

PASTA pursues a mixed-method and multilevel approach that is consistently applied in seven case study cities. Determinants of AM and the evaluation of measures to increase AM are investigated through a large scale longitudinal survey, with overall 14,000 respondents participating in Antwerp, Barcelona, London, Örebro, Rome, Vienna and Zurich. Contextual factors are systematically gathered in each city. PASTA generates empirical findings to improve HIA for AM, for example, with estimates of crash risks, factors on AM-PA substitution and carbon emissions savings from mode shifts. Findings from PASTA will inform WHO's online Health Economic Assessment Tool on the health benefits from cycling and/or walking. The study's wide scope, the combination of qualitative and quantitative methods and health and transport methods, the innovative survey design, the general and city-specific analyses, and the transdisciplinary composition of the consortium and the wider network of partners promise highly relevant insights for research and practice.

ETHICS AND DISSEMINATION

Ethics approval has been obtained by the local ethics committees in the countries where the work is being conducted, and sent to the European Commission before the start of the survey. The PASTA website (http://www.pastaproject.eu) is at the core of all communication and dissemination activities.

Built environment effects on cyclist injury severity in automobile-involved bicycle crashes

This analysis uses a generalized ordered logit model and a generalized additive model to estimate the effects of built environment factors on cyclist injury severity in automobile-involved bicycle crashes, as well as to accommodate possible spatial dependence among crash locations. The sample is drawn from the Seattle Department of Transportation bicycle collision profiles. This study classifies the cyclist injury types as property damage only, possible injury, evident injury, and severe injury or fatality. Our modeling outcomes show that: (1) injury severity is negatively associated with employment density; (2) severe injury or fatality is negatively associated with land use mixture; (3) lower likelihood of injuries is observed for bicyclists wearing reflective clothing; (4) improving street lighting can decrease the likelihood of cyclist injuries; (5) posted speed limit is positively associated with the probability of evident injury and severe injury or fatality; (6) older cyclists appear to be more vulnerable to severe injury or fatality; and (7) cyclists are more likely to be severely injured when large vehicles are involved in crashes. One implication drawn from this study is that cities should increase land use mixture and development density, optimally lower posted speed limits on streets with both bikes and motor vehicles, and improve street lighting to promote bicycle safety. In addition, cyclists should be encouraged to wear reflective clothing.

Physical Activity through Sustainable Transport Approaches (PASTA): protocol for a multi-centre, longitudinal study

Background

Physical inactivity is one of the leading risk factors for non-communicable diseases, yet many are not sufficiently active. The Physical Activity through Sustainable Transport Approaches (PASTA) study aims to better understand active mobility (walking and cycling for transport solely or in combination with public transport) as an innovative approach to integrate physical activity into individuals’ everyday lives. The PASTA study will collect data of multiple cities in a longitudinal cohort design to study correlates of active mobility, its effect on overall physical activity, crash risk and exposure to traffic-related air pollution.

Methods/Design

A set of online questionnaires incorporating gold standard approaches from the physical activity and transport fields have been developed, piloted and are now being deployed in a longitudinal study in seven European cities (Antwerp, Barcelona, London, Oerebro, Rome, Vienna, Zurich). In total, 14000 adults are being recruited (2000 in each city). A first questionnaire collects baseline information; follow-up questionnaires sent every 13 days collect prospective data on travel behaviour, levels of physical activity and traffic safety incidents. Self-reported data will be validated with objective data in subsamples using conventional and novel methods. Accelerometers, GPS and tracking apps record routes and activity. Air pollution and physical activity are measured to study their combined effects on health biomarkers. Exposure-adjusted crash risks will be calculated for active modes, and crash location audits are performed to study the role of the built environment. Ethics committees in all seven cities have given independent approval for the study.

Discussion

The PASTA study collects a wealth of subjective and objective data on active mobility and physical activity. This will allow the investigation of numerous correlates of active mobility and physical activity using a data set that advances previous efforts in its richness, geographical coverage and comprehensiveness. Results will inform new health impact assessment models and support efforts to promote and facilitate active mobility in cities.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2453-3) contains supplementary material, which is available to authorized users.

Exposure measurement in bicycle safety analysis: A review of the literature

BACKGROUND

Cycling, as an active mode of transportation, has well-established health benefits. However, the safety of cyclists in traffic remains a major concern. In-depth studies of potential risk factors and safety outcomes are needed to ensure the most appropriate actions are taken to improve safety. However, the lack of reliable exposure data hinders meaningful analysis and interpretation. In this paper, we review the bicycle safety literature reporting different methods for measuring cycling exposure and discuss their findings.

METHODS

A literature search identified studies on bicycle safety that included a description of how cycling exposure was measured, and what exposure units were used (e.g. distance, time, trips). Results were analyzed based on whether retrospective or prospective measurement of exposure was used, and whether safety outcomes controlled for exposure.

RESULTS

We analyzed 20 papers. Retrospective studies were dominated by major bicycle accidents, whereas the prospective studies included minor and major bicycle accidents. Retrospective studies indicated higher incidence rates (IR) of accidents for men compared to women, and an increased risk of injury for cyclists aged 50 years or older. There was a lack of data for cyclists younger than 18 years. The risk of cycling accidents increased when riding in the dark. Wearing visible clothing or a helmet, or having more cycling experience did not reduce the risk of being involved in an accident. Better cyclist-driver awareness and more interaction between car driver and cyclists, and well maintained bicycle-specific infrastructure should improve bicycle safety.

CONCLUSION

The need to include exposure in bicycle safety research is increasingly recognized, but good exposure data are often lacking, which makes results hard to interpret and compare. Studies including exposure often use a retrospective research design, without including data on minor bicycle accidents, making it difficult to compare safety levels between age categories or against different types of infrastructure. Future research should focus more on children and adolescents, as this age group is a vulnerable population and is underrepresented in the existing literature.

Health impact assessment of active transportation: A systematic review

OBJECTIVE

Walking and cycling for transportation (i.e. active transportation, AT), provide substantial health benefits from increased physical activity (PA). However, risks of injury from exposure to motorized traffic and their emissions (i.e. air pollution) exist. The objective was to systematically review studies conducting health impact assessment (HIA) of a mode shift to AT on grounds of associated health benefits and risks.

METHODS

Systematic database searches of MEDLINE, Web of Science and Transportation Research International Documentation were performed by two independent researchers, augmented by bibliographic review, internet searches and expert consultation to identify peer-reviewed studies from inception to December 2014.

RESULTS

Thirty studies were included, originating predominantly from Europe, but also the United States, Australia and New Zealand. They compromised of mostly HIA approaches of comparative risk assessment and cost-benefit analysis. Estimated health benefit-risk or benefit-cost ratios of a mode shift to AT ranged between -2 and 360 (median=9). Effects of increased PA contributed the most to estimated health benefits, which strongly outweighed detrimental effects of traffic incidents and air pollution exposure on health.

CONCLUSION

Despite different HIA methodologies being applied with distinctive assumptions on key parameters, AT can provide substantial net health benefits, irrespective of geographical context.

An exposure based study of crash and injury rates in a cohort of transport and recreational cyclists in New South Wales, Australia

This paper examines self-reported prospectively collected data from 2038 adult transport and recreational cyclists from New South Wales (Australia) to determine exposure-based incident crash and injury rates. During 25,971 days of cycling, 198 crashes were reported, comprising approximately equal numbers of falls and collisions. The overall crash rate was 0.290 (95% CI, 0.264-0.319) per 1000km or 6.06 (95% CI, 5.52-6.65) per 1000h of travel. The rate of crashes causing any injury (self-treated, or medically attended without overnight hospital stay) was 0.148 (95% CI, 0.133-0.164) per 1000km or 3.09 (95% CI, 2.79-3.43) per 1000h of travel. The rate of crashes causing a medically attended injury (without overnight hospital stay) was 0.023 (95% CI, 0.020-0.027) per 1000km or 0.49 (95% CI, 0.43-0.56) per 1000h of travel. No injuries requiring an overnight stay in hospital were reported on days meeting the inclusion criteria. After adjustment for exposure in hours, or for the risks associated with different infrastructure utilisation, the rates of crashes and medically attended injuries were found to be greater for females than males, less experienced than more experienced cyclists, and for those who rode mainly for transport rather than mainly for recreation. Comparison of estimated crash and injury rates on different infrastructure types were limited by the small number of events, however findings suggest that the separation of cyclists from motorised traffic is by itself not sufficient to ensure safe cycling.

Road crash fatality rates in France: a comparison of road user types, taking account of travel practices

BACKGROUND

Travel practices are changing: bicycle and motorized two-wheeler (MTW) use are rising in some of France's large cities. These are cheaper modes of transport and therefore attractive at a time of economic crisis, but they also allow their users to avoid traffic congestion. At the same time, active transport modes such as walking and cycling are encouraged because they are beneficial to health and reduce pollution. It is therefore important to find out more about the road crash risks of the different modes of transport. To do this, we need to take account of the number of individuals who use each, and, even better, their travel levels.

METHOD

We estimated the exposure-based fatality rates for road traffic crashes in France, on the basis of the ratio between the number of fatalities and exposure to road accident risk. Fatality data were obtained from the French national police database of road traffic casualties in the period 2007-2008. Exposure data was estimated from the latest national household travel survey (ENTD) which was conducted from April 2007 to April 2008. Three quantities of travel were computed for each mode of transport: (1) the number of trips, (2) the distance traveled and (3) the time spent traveling. Annual fatality rates were assessed by road user type, age and sex.

RESULTS

The overall annual fatality rates were 6.3 per 100 million trips, 5.8 per billion kilometers traveled and 0.20 per million hours spent traveling. The fatality rates differed according to road user type, age and sex. The risk of being killed was 20 to 32 times higher for motorized two-wheeler users than for car occupants. For cyclists, the risk of being killed, both on the basis of time spent traveling and the number of trips was about 1.5 times higher than for car occupants. Risk for pedestrians compared to car occupants was similar according to time spent traveling, lower according to the number of trips and higher according to the distance traveled. People from the 17-20 and 21-29 age groups and those aged 70 and over had the highest rates. Males had higher rates than females, by a factor of between 2 and 3.

CONCLUSION

When exposure is taken into account, the risks for motorized two-wheeler users are extremely high compared to other types of road user. This disparity can be explained by the combination of speed and a lack of protection (except for helmets). The differential is so great that prevention measures could probably not eliminate it. The question that arises is as follows: with regard to public health, should not the use of MTW, or at least of motorcycles, be deterred? The difference between the fatality risk of cyclists and of car occupants is much smaller (1.5 times higher); besides, there is much room for improvements in cyclist safety, for instance by increasing the use of helmets and conspicuity equipment. Traffic calming could also benefit cyclists, pedestrians and perhaps moped users.

Perceived traffic risk for cyclists: the impact of near miss and collision experiences

Though the percentage of people bicycling for transportation rose during the last decade, with an average increase in bicycle commuting of 47% (Flusche, 2012), still only 1% of all U.S. trips are made by bike (Flusche, 2010). Research suggests that people's concern regarding the risk of bicycling near traffic-namely the risk of being hit by a car-remain a significant barrier to widespread cycling. However, research has not disaggregated traffic risk to expose its many aspects and how they may affect bicyclists with differing skill levels, experiences, and behaviors. This study begins to address this gap in our understanding. Elaborating on results from an internet survey, this study examined various aspects of traffic risk among 406 potential and current bicyclists in the San Francisco Bay Area. The data indicate that perceived traffic risk negatively influences the decision to bicycle for potential and occasional bicyclists, although the influence decreases with cycling frequency. Additionally, cycling frequency seems to heighten awareness of traffic risk, particularly for cyclists who have experienced "near misses" or collisions. In particular, near misses were found to be (a) much more common than collisions and (b) more strongly associated than collisions with perceived traffic risk. The findings suggest that efforts targeting road user behaviors and roadway designs associated with these near misses could mitigate perceived and actual traffic risk for bicyclists, and thereby eventually help achieve higher cycling ridership.

Bicycling crash circumstances vary by route type: a cross-sectional analysis

Background

Widely varying crash circumstances have been reported for bicycling injuries, likely because of differing bicycling populations and environments. We used data from the Bicyclists’ Injuries and the Cycling Environment Study in Vancouver and Toronto, Canada, to describe the crash circumstances of people injured while cycling for utilitarian and leisure purposes. We examined the association of crash circumstances with route type.

Methods

Adult cyclists injured and treated in a hospital emergency department described their crash circumstances. These were classified into major categories (collision vs. fall, motor vehicle involved vs. not) and subcategories. The distribution of circumstances was tallied for each of 14 route types defined in an earlier analysis. Ratios of observed vs. expected were tallied for each circumstance and route type combination.

Results

Of 690 crashes, 683 could be characterized for this analysis. Most (74%) were collisions. Collisions included those with motor vehicles (34%), streetcar (tram) or train tracks (14%), other surface features (10%), infrastructure (10%), and pedestrians, cyclists, or animals (6%). The remainder of the crashes were falls (26%), many as a result of collision avoidance manoeuvres. Motor vehicles were involved directly or indirectly with 48% of crashes. Crash circumstances were distributed differently by route type, for example, collisions with motor vehicles, including “doorings”, were overrepresented on major streets with parked cars. Collisions involving streetcar tracks were overrepresented on major streets. Collisions involving infrastructure (curbs, posts, bollards, street furniture) were overrepresented on multiuse paths and bike paths.

Conclusions

These data supplement our previous analyses of relative risks by route type by indicating the types of crashes that occur on each route type. This information can guide municipal engineers and planners towards improvements that would make cycling safer.