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Under-reporting bicycle accidents to police in the COST TU1101 international survey: Cross-country comparisons and associated factors
Get PDFPolice 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.acceptedVersio
An Empirical Bayes before-after evaluation of road safety effects of a new motorway in Norway
Get PDFThis paper presents an Empirical Bayes before-after evaluation of the road safety effects of a new motorway (freeway) in Østfold county, Norway. The before-period was 1996–2002. The after-period was 2009–2015. The road was rebuilt from an undivided two-lane road into a divided four-lane road. The number of killed or seriously injured road users was reduced by 75 percent, controlling for (downward) long-term trends and regression-to-the-mean (statistically significant at the 5 percent level; recorded numbers 71 before, 11 after). There were small changes in the number of injury accidents (185 before, 123 after; net effect −3%) and the number of slightly injured road users (403 before 279 after; net effect +5%). Motorways appear to mainly reduce injury severity, not the number of accidents. The paper discusses challenges in implementing the Empirical Bayes design when less than ideal data are available.acceptedVersio
Analysing the influence of visible roadwork activity on drivers’ speed choice at work zones using a video-based experiment
No full textRenata Torquato Steinbakk, Pål Ulleberg, Fridulv Sagberg, Knut Inge Fostervold, Analysing the influence of visible roadwork activity on drivers’ speed choice at work zones using a video-based experiment, Transportation Research Part F: Traffic Psychology and Behaviour, Volume 44, 2017, Pages 53-62, ISSN 1369-8478, https://doi.org/10.1016/j.trf.2016.10.003.The present study used a video-based experimental design to investigate the influence of visible roadwork activity on speed preferences at work zones. Four videos from real work zones in Norway were used. Two roadwork areas were filmed at two moments – with and without visible roadwork activity. A total of 815 drivers watched two videos and answered a questionnaire online. Participants stated speed preferences for both videos and then evaluated the influence of 17 common work zone elements on their speed choice. The results showed lower preferred speeds for the videos with visible roadwork activity. The elements considered by drivers to influence their speed included speed regulation (e.g. speed limit signs), transient motives (e.g. time pressure), flow pressure (e.g. speed of the rear driver) and situational conditions (e.g. road situation). Results from the regression analysis showed that visible roadwork activity was the strongest predictor of lower preferred speeds. Speed regulation and transient motives were also significant predictors of preferred speeds. Those who considered speed regulation more important to influence their speed choice at work zones were likely to state lower preferred speeds, while those who considered transient motives as more important were likely to state higher preferred speeds. These findings support the hypothesis that visible roadwork activity is an important factor for lower speed preferences at work zones. The main practical implication is that road authorities should consider various countermeasures to achieve safe driving speeds at work zones, not only roadworks warning signs.Analysing the influence of visible roadwork activity on drivers’ speed choice at work zones using a video-based experimentacceptedVersio
Sharing is (s)caring? Interactions between buses and bicyclists on bus lanes shared with bicyclists
No full textTim De Ceunynck, Bert Dorleman, Stijn Daniels, Aliaksei Laureshyn, Tom Brijs, Elke Hermans, Geert Wets, Sharing is (s)caring? Interactions between buses and bicyclists on bus lanes shared with bicyclists, Transportation Research Part F: Traffic Psychology and Behaviour, Volume 46, Part B, 2017, Pages 301-315, ISSN 1369-8478, https://doi.org/10.1016/j.trf.2016.09.028.This paper presents the results of an observation study of interactions between bicyclists and buses on shared bus lanes. The aim of the paper is to analyse bicyclists’ safety on bus lanes shared with bicyclists. Straight sections of two bus lanes shared with bicyclists in Belgium are observed. All interactions between bicyclists and buses over two full weeks are recorded and analysed. Additionally, the lateral position and riding speed of bicyclists that are in interaction with buses are compared with the behaviour of bicyclists that are not in interaction with buses. One of the observed bus lanes is in line with road design guidelines in a number of countries that state that a sufficiently narrow bus lane (<3.5 m) is hypothesised to be safer than a somewhat wider bus lane; the other observed bus lane is deemed too wide according to these guidelines and is hypothesised to lead to close overtaking manoeuvres. The results show that close interactions between bicyclists and buses are relatively frequent on both types of analysed bus lanes. Close overtaking manoeuvres (a bus overtakes a bicyclist with a lateral distance less than 1 m) as well as close bicycle-following situations (a bus drives behind a bicyclist with a time gap less than 2 s) are quite common on both analysed bus lanes. The analyses could not confirm the hypothesis that a sufficiently narrow bus lane is safer than a wider bus lane. On the contrary, close interactions seem even slightly more common on the narrower bus lane. Slightly more close overtaking manoeuvres take place on the narrower bus lane, but the difference is not statistically significant. Additionally, more bicycle-following situations take place on the narrower bus lane because overtaking is more difficult. The results show that buses often maintain a close time gap in these situations. The overtaking speed of the buses is, however, significantly higher on the wider bus lane compared to the narrower one. Moreover, the presence of a bus has an influence on the behaviour of bicyclists. Bicyclists who get overtaken by a bus ride more closely to the edge of the road than bicyclists who are not in interaction with a bus. While the road design guidelines assume that bicyclists take up a width of one meter from the edge on bus lanes shared with bicyclists, the observations show that bicyclists take up much less space while being overtaken. The presence of a bus does not have a significant influence on the standard deviation of the lateral position of the bicyclist. On the narrower bus lane, some findings suggest that bicyclists who are involved in an interaction with a bus ride faster than bicyclists who are not involved in an interaction with a bus.Sharing is (s)caring? Interactions between buses and bicyclists on bus lanes shared with bicyclistsacceptedVersio
A generic discrete choice model of automobile purchase
Get PDFPurpose The introduction of novel fuel and propulsion technologies, such as battery, (plug-in) hybrid and fuel cell electric vehicles, and the need to combat the exhaust emission of local and global pollutants from the passenger car fleet have enhanced the political interest in the vehicle purchase choices made by private households and firms, and in how these choices can be influenced through fiscal and regulatory penalties and incentives. Methods As a tool to understand and analyse such questions, we have developed a generic nested logit model of automobile choice, based on complete disaggregate vehicle sales data for Norway for the period ranging from January 1996 until July 2011. The data set contains 1.6 million vehicle transactions. Results Being sensitive to changes in the vehicle purchase tax and the fuel tax, the model discriminates well between various fiscal policy scenarios. In using the model for such purposes, one is greatly helped by the fact that the model distinguishes between price changes due to taxation and those originating from the manufacturing or marketing side. Conclusions The strongly CO2 graduated vehicle purchase tax, with exemptions granted for battery electric vehicles, is shown to have a major impact on the average type approval rate of CO2 emissions from new passenger cars registered in Norway. The fuel tax also helps induce car customers to buy low emission vehicles.publishedVersio
From cars to bikes – the feasibility and effect of using e-bikes, longtail bikes and traditional bikes for transportation among parents of children attending kindergarten: design of a randomized cross-over trial
Get PDFBackground
The present study aims to increase bicycling and level of physical activity (PA), and thereby promote health in parents of toddlers, by giving access to different bicycle types. There is a need for greater understanding of e-bikes and their role in the transportation network, and further effects on PA levels and health. Moreover, longtail bikes could meet certain practical needs not fulfilled by e-bikes or traditional bikes, hence increased knowledge regarding their feasibility should be obtained. No previous studies have investigated whether providing an e-bike or a longtail bike over an extended period in a sample of parents of toddlers influence objectively assessed amount of bicycling and total PA level, transportation habits, cardiorespiratory fitness, body composition and blood pressure.
Methods
A randomized cross-over trial will be performed, entailing that participants in the intervention group (n = 18) complete the following intervention arms in random order: (i) three months access to an e-bicycle with trailer for child transportation (n = 6), (ii) three months access to a longtail bicycle (n = 6), and (iii) three months access to a regular bicycle with trailer (n = 6), in total nine months. Also, a control group (n = 18) maintaining usual transportation and PA habits will be included. A convenience sample consisting of 36 parents of toddlers residing in Kristiansand municipality, Southern Norway, will be recruited. Total amount of bicycling (distance and time), total level of PA, and transportation habits will be measured at baseline and in connection to each intervention arm. Cardiorespiratory fitness, body composition and blood pressure will be measured at baseline and post-intervention. Main outcome will be bicycling distance and time spent cycling.
Discussion
New knowledge relevant for the timely issues of public health and environmental sustainability will be provided among parents of toddlers, representing a target group of greatest importance. There is a call for research on the influence of e-bikes and longtail bikes on travel behavior and PA levels, and whether voluntary cycling could improve health. If the present study reveals promising results, it should be replicated in larger and more representative samples. Eventually, inclusion in national public health policies should be considered.publishedVersio
Food Scares: Reflections and Reactions
Get PDFThe aim of this study is to investigate consumers’ reflections and reactions to a food scare news story. Previous studies indicate that risk communication not always is able to influence people’s behavior and that pre-existing attitudes may influence people’s reactions and reflections. In this study, we investigate how consumers critically reflect and emotionally react to a food scare, here defined as risk communication that spirals public anxiety over food safety incidents, and leads to an unwanted escalation in media attention. Fall 2014, a researcher from the Norwegian Institute of Public Health said in a newspaper interview that she never touched chicken with her bare hands. This interview was the beginning of a media storm, which resulted in a dramatic drop in sales of chicken. In this study, we explore a small group of consumers’ reflections and reactions to this news article. Data from five focus group interviews with Norwegian consumers of chicken were transcribed, content analyzed, and coded, before we conducted a multiple correspondence analysis and a hierarchical cluster analysis in JMP Pro 12. The findings indicate that consumers do reflect when confronted with a food scare story. Some question the research behind the news, others compare the food scare’s danger to other risks. Even though consumers do reflect around the facts in the food scare article, their emotions seem to affect their behavior more systematic than their reflections.Food Scares: Reflections and ReactionspublishedVersio
Does valuation research provide a credible basis for cost-benefit analysis of safety measures?
Get PDFMany studies have been made to obtain a monetary valuation of reduced risk of death, usually given as the value of a statistical life (VSL), which is a reduction in risk corresponding to the prevention of one fatality. This paper asks whether valuation research provides a credible basis for cost-benefit analysis of safety measures. A cost benefit analysis is credible if its results cannot be criticised by reference to the valuation studies forming its basis. It is argued that a credible basis for cost-benefit analysis in this sense does not exist. The monetary valuations of a statistical life vary enormously. The enormous diversity in values is increasingly accepted by researchers working in the field as inevitable and consistent with individual utility maximisation, and thus not necessarily anomalous. Some recent contributions argue that the value of a statistical life ought to vary depending on, for example income. Such reformulations of the theory underlying valuation studies mean that the choice of a particular value of a statistical life within the huge range of such values is not necessarily more justified than the choice of a different value.submittedVersio
How can cyclist injuries be included in health impact economic assessments?
Get PDFThis paper discusses how injuries sustained while cycling can be included as a component of health impact economic assessment of increased cycling. To include injuries as a component of a health impact assessment, their expected frequency of occurrence and impacts on health must well known. In this respect, incomplete reporting of cyclist injuries in official accident statistics is an obstacle for good health impact assessment. It is convenient to represent injuries in terms of an expected loss of health per cyclist or kilometre cycled, which can be converted to monetary terms to make it comparable with the health benefits. It is suggested that stating health loss in terms of DALYs (Disability Adjusted Life Years) is suitable for this purpose. Examples are given of how to estimate the health loss associated with bicycle injuries. It is more difficult to model the probability of injury. Two approaches are compared. One approach relies on the relationship between distance cycled per year and risk of injury. The other approach is based on the concept of safety-in-numbers. The number of injuries is modelled as a function of the number of cyclists and motor vehicles. Results are found to be greatly influenced by the assumptions made about whether increased cycling occurs as a result of modal shift from motor vehicles or not.acceptedVersio
Plan for sustainable urban logistics – comparing between Scandinavian and UK practices
Get PDFIntroduction Common practices in current urban logistics planning in Scandinavia and the UK, and the degree to which SUTP (Sustainable Urban Transport Plan), SUMP (Sustainable Urban Mobility Plans) and SULP (Sustainable Urban Logistics Plans) guidelines are used, are examined in this paper. Methods A systematic literature review identifies relevant studies based on predefined inclusion criteria: mobility, freight, urban, plan. Results It is found that urban freight plans are used more frequently in the UK than in the Scandinavian countries. SULPs (freight strategies, action plans or parts of a mobility plan) follow a structure that identifies the current situation and defines the strategic context, vision, targets and objectives using selected policy measures, measures that are dependent on geographical scope. Conclusions Urban freight plans are designed with a sustainability perspective to define visions and policy measures for urban freight. SUTP, SUMP and SULP methodologies are used in existing Scandinavian and UK urban freight plans, especially when a collaborative planning approach is being practiced. The emphasis on urban freight is challenged by the regional perspective. Integrating urban freight in general planning procedures or transport planning is important. Government guidance and sustainable strategies can provide a planning methodology and, therefore, based on national guidelines further European structural standardisation could be beneficial. Identification of freight plans is crucial if the contributions they make are to be determined.publishedVersio