De Craen S.,SWOV Institute for Road Safety Research |
Doumen M.J.A.,SWOV Institute for Road Safety Research |
Van Norden Y.,SWOV Institute for Road Safety Research
Accident Analysis and Prevention | Year: 2014
The most common type of conflict in which a motorcyclist is injured or killed is a collision between a motorcycle and a car, often in priority situations. Many studies on motorcycle safety focus on the question why car drivers fail to give priority and on the poor conspicuity of motorcycles. The concept of 'looked-but-failed-to-see' crashes is a recurring item. On the other hand, it is not entirely unexpected that motorcycles have many conflicts with cars; there simply are so many cars on the road. This paper tries to unravel whether - acknowledging the differences in exposure - car drivers indeed fail to yield for motorcycles more often than for other cars. For this purpose we compared the causes of crashes on intersections (e.g. failing to give priority, speeding, etc.) between different crash types (car-motorcycle or car-car). In addition, we compared the crash causes of dual drivers (i.e. car drivers who also have their motorcycle licence) with regular car drivers. Our crash analysis suggests that car drivers do not fail to give priority to motorcycles relatively more often than to another car when this car/motorcycle approaches from a perpendicular angle. There is only one priority situation where motorcycles seem to be at a disadvantage compared to cars. This is when a car makes a left turn, and fails to give priority to an oncoming motorcycle. This specific crash scenario occurs more often when the oncoming vehicle is a motorcycle than when it is a car. We did not find a significant difference between dual drivers and regular car drivers in how often they give priority to motorcycles compared to cars. © 2013 Elsevier Ltd. All rights reserved.
Papadimitriou E.,National Technical University of Athens |
Yannis G.,National Technical University of Athens |
Bijleveld F.,SWOV Institute for Road Safety Research |
Cardoso J.L.,National Laboratory for Civil Engineering
Accident Analysis and Prevention | Year: 2013
The objective of this paper is the analysis of the state-of-the-art in risk indicators and exposure data for safety performance assessment in Europe, in terms of data availability, collection methodologies and use. More specifically, the concepts of exposure and risk are explored, as well as the theoretical properties of various exposure measures used in road safety research (e.g. vehicle- and person-kilometres of travel, vehicle fleet, road length, driver population, time spent in traffic, etc.). Moreover, the existing methods for collecting disaggregate exposure data for risk estimates at national level are presented and assessed, including survey methods (e.g. travel surveys, traffic counts) and databases (e.g. national registers). A detailed analysis of the availability and quality of existing risk exposure data is also carried out. More specifically, the results of a questionnaire survey in the European countries are presented, with detailed information on exposure measures available, their possible disaggregations (i.e. variables and values), their conformity to standard definitions and the characteristics of their national collection methods. Finally, the potential of international risk comparisons is investigated, mainly through the International Data Files with exposure data (e.g. Eurostat, IRTAD, ECMT, UNECE, IRF, etc.). The results of this review confirm that comparing risk rates at international level may be a complex task, as the availability and quality of exposure estimates in European countries varies significantly. The lack of a common framework for the collection and exploitation of exposure data limits significantly the comparability of the national data. On the other hand, the International Data Files containing exposure data provide useful statistics and estimates in a systematic way and are currently the only sources allowing international comparisons of road safety performance under certain conditions. © 2013 Elsevier Ltd. All rights reserved.
Twisk D.A.M.,SWOV Institute for Road Safety Research |
Reurings M.,SWOV Institute for Road Safety Research
Accident Analysis and Prevention | Year: 2013
To curtail the rising numbers of cyclists seriously injured in road crashes, more insights are needed into the factors that contribute to these crashes. For instance, darkness is known to be associated with higher injury rates, but little is known about the relative influence of factors such as poor conspicuity, impaired perception and alcohol use among cyclists. To examine these factors, the present study analyzed the epidemiological crash data for three meteorological light conditions: daylight, late evening darkness and early morning darkness; for two crash types: crashes with (M-crashes) and without motorized traffic (NM-crashes); and for different age groups. The relative injury rates (injury risk per distance travelled in darkness corrected for daylight injury risks for each age group) confirmed findings from earlier studies that cycling in late evening darkness is associated with higher injury rates than cycling in daylight conditions. This is the case for both crash types with only small differences between the age groups suggesting that poor conspicuity (M-crashes) and impaired perception (NM-crashes) may play a role. In comparison to late evening darkness, relative injury rates in early morning darkness are much higher. This is the case for both crash types with large differences among the age groups, suggesting that in addition to the absence of daylight also age related risk factors are at play. Support for this hypothesis was found from the analyses of hospital records, showing that the proportion of seriously injured cyclists who have been drinking is highest in early morning darkness and has strongly increased over the last decades. These insights provide input for the selection of countermeasures such as improved lighting (both street and bicycle lights) and interventions targeting alcohol use among cyclists. © 2013 Published by Elsevier Ltd.
Vlakveld W.P.,SWOV Institute for Road Safety Research
Transportation Research Part F: Traffic Psychology and Behaviour | Year: 2014
In PC-based hazard perception tests scores are traditionally based on how quickly participants respond to developing hazards in video clips. A disadvantage of this method is that latent hazards which do not develop into acute threats cannot be included in the test. The present study compared two tasks using the same stimuli but with different response methods. The stimuli consisted of thirteen animated video clips in which latent hazards did not materialize. Latent hazards could either be a visible other road user who due to the circumstances could start to act dangerously, or a hidden other road users who could be on collision course. The first-mentioned were the overt latent hazards and the latter were the covert latent hazards. In Task 1, participants had to indicate what the high priority latent hazard was after they had watched a clip. In Task 2, participants could indicate latent hazards while they were watching a clip and decide afterwards which of the indicated latent hazards had the highest priority. In both tasks the scores were based on how many high priority latent hazards were detected and were not based not on response times. Professional drivers (driver trainers and driving examiners) and learner drivers were randomly assigned to a group that performed Task 1 and a group that performed Task 2. Professionals scored significantly better on both tasks than learner drivers. Although in both tasks professionals scored significantly higher, Task 1 seems to be a more promising alternative for the traditional hazard perception test than Task 2 because professional drivers scored significantly higher on overt latent hazards than learner drivers in Task 1 but not in Task 2 and experience with computer games influenced the scores in Task 2 but not in Task 1. A weakness of Task 1 was its rather low internal consistency (α =.69). © 2013 Elsevier Ltd. All rights reserved.
Wegman F.,SWOV Institute for Road Safety Research |
Oppe S.,SWOV Institute for Road Safety Research
Safety Science | Year: 2010
In order to obtain political interest in road safety problems and to learn from other countries' 'good practices', it is often helpful to compare one's own safety situation with that of other countries. In a number of projects tools have been developed for such comparisons. These tools range from simple ratings of countries on their safety outcomes, such as the annual number of fatalities per capita or per kilometre driven by (motor)vehicles to more comprehensive comparisons.These comparisons not only show differences in safety between countries, but to a certain extent also explain such differences in terms of their safety background and measures taken. Finally, tools have been defined to support road safety policy makers in developing possible safety measures or actions. Procedures for such complex safety comparisons have been developed and tested in several so-called SUNflower studies.This promising approach can be further developed into standard procedures for safety comparisons between all countries in the European Union, and other countries worldwide. This paper wishes to outline the development of such standards for the benchmarking of road safety and safety trends as well as procedures for quantifying safety performances of countries.Starting point of this conceptual framework is the so-called SUNflower-pyramid in which three types of indicators are distinguished. The first one of these, the road safety performance indicator, is called an outcome indicator and is based on the number of killed and injured road users. The second indicator type indicates the quality of the implementation of road safety policies: the implementation performance indicators. The third type of indicator indicates the quality of response in policy documents to improve road safety (policy performance indicator). The three types of indicators are embedded in a policy context: the structure and culture of a country, which are considered as background variables.This paper sets out to describe the framework for the development of a comprehensive set of indicators to benchmark road safety performances of countries or of sub-national jurisdictions. The paper also discusses the advantages and disadvantages of combining such indicators and if combined, how to aggregate how different indicators in one composite performance index. It is argued to group countries in different classes with more or less comparable countries. Different procedures are used for this grouping. The results are promising and it is recommended to work with classes of countries. © 2010 Elsevier Ltd.
Wegman F.,SWOV Institute for Road Safety Research |
Zhang F.,SWOV Institute for Road Safety Research |
Dijkstra A.,SWOV Institute for Road Safety Research
Accident Analysis and Prevention | Year: 2012
This paper discusses the current level of the road safety problems of cycling and cyclists, why cyclists run relatively high risks, and why cyclists may be considered as 'vulnerable road users'. This paper is based on peer-reviewed research which give some idea how to reduce the number of cyclist casualties. However, this research is rather limited and the results cannot (easily) be transferred from one setting or country to another: generalization of results should only be done with the utmost care, if it is to be done at all. Interventions to reduce cyclist casualties worldwide seem to be of an incidental nature; that is to say, they are implemented in a rather isolated way. In a Safe System approach, such as the Dutch Sustainable Safety vision, the inherent risks of traffic are dealt with in a systematic, proactive way. We illustrate how this approach is especially effective for vulnerable road users, such as cyclists. Finally, the paper addresses the question of whether it is possible to make more cycling good for road safety. We conclude that when the number of cyclists increases, the number of fatalities may increase, but will not necessarily do so, and the outcome is dependent on specific conditions. There is strong evidence that well-designed bicycle facilities - physically separated networks - reduce risks for cyclists, and therefore have an impact on the net safety result, for example if car-kilometres are substituted by bicycle kilometres. Policies to support cycling should incorporate these findings in order to make more cycling good for road safety. © 2010 Elsevier Ltd. All rights reserved.
Dijkstra A.,SWOV Institute for Road Safety Research
Transportation Research Part C: Emerging Technologies | Year: 2013
In the Netherlands, the concept 'Sustainable Safety' is the leading vision in road safety policy and research. The main goal of a sustainably safe road transport system is to reduce the annual number of road crash casualties to a fraction of the current levels. An important requirement that follows from this vision is that the quickest route and the safest route should coincide. This paper focuses on the design of a method which enables the planner to establish the safety effects of existing route choice, and also those of changes in route choice. The traffic safety assessment is carried out by quantifying the safety level of a route on the basis of those characteristics of the route that are assumed to be related to safety. This paper examines the quantitative relationship between the assessment of the route's safety level and the conflicts (at junctions) involving vehicles travelling along that route. These conflicts are detected in a micro-simulation model. Different routes in a regional network which were travelled by the modeled vehicles were used for the analysis.This method of quantifying the safety level of routes will make it possible to evaluate road network structures from a safety perspective. It is expected that by optimising the design of the network and by influencing route choice a (more) sustainably safe traffic system can be achieved. © 2012 Elsevier Ltd.
Weijermars W.,SWOV Institute for Road Safety Research |
Wegman F.,SWOV Institute for Road Safety Research
Transportation Research Record | Year: 2011
In the 1990s, the Institute for Road Safety Research (SWOV) in the Netherlands introduced the vision of sustainable safety. In a sustainably safe traffic system, crashes are prevented as much as possible, and when prevention is not possible, the probability of severe injury is reduced to almost zero. In 1998, implementation of the vision commenced with the start-up program. Ten years after the start-up program, there was an investigation of how implementation of the measures that emanated from or were in line with the vision of sustainable safety had progressed and what effects these measures have had on safety. The assessment indicated that a substantial number of traffic safety measures were implemented from 1998 through 2007. Many actions taken within the framework of the start-up program were aimed at improving infrastructure safety; the most important actions were categorization of the road network and traffic calming measures such as the construction of 30-and 60-km/h zones. In addition, traffic enforcement increased as a result of the establishment of dedicated regional traffic enforcement teams. The crashworthiness of vehicles also improved. These measures had a positive effect on traffic safety. Each individual measure prevented casualties. Moreover, the fatality rate decreased from 7.3 fatalities per billion kilometers traveled in 1998 to 4.7 per billion in 2007. It is estimated that together the measures prevented 300 to 400 fatalities in 2007 (32% to 34% fewer than expected) and 1,600 to 1,700 fatalities from 1998 through 2007. Finally, a benefit-cost analysis indicates that the measures were also cost beneficial (benefit-cost ratio 3.6:1).
Reurings M.C.B.,SWOV Institute for Road Safety Research |
Stipdonk H.L.,SWOV Institute for Road Safety Research
Annals of Epidemiology | Year: 2011
Purpose: This paper describes a new estimation method of the number of road injuries in The Netherlands. Methods: The bases for this method are the hospital inpatient registry and the police crash record database. Both databases contain errors and omissions. The police database in particular suffers from serious underreporting, and is also inaccurate in indicating injury severity. The hospital database is inaccurate in indicating that a patient was involved in a road crash. Nonetheless, in principle it contains all serious road injuries. After linking both databases an estimating method, inspired by capture-recapture, was used to estimate the number of road injuries. The differences in registration for transport mode, injury severity, and region of crash have been taken into account. Results: This leads to an estimation of the number of serious road injuries in the Netherlands in 1993-2008. Conclusions: We found that 85% of the road injuries are recognizable as such in the hospital registry. The registration rate of the police registry is different for road injuries in crashes involving motorized vehicles (58% in 2008) and for road injuries in crashes not involving motorized vehicles (4% in 2008). © 2011 Elsevier Inc.
Aarts L.T.,SWOV Institute for Road Safety Research |
Houwing S.,SWOV Institute for Road Safety Research
Transportation Research Part A: Policy and Practice | Year: 2015
The method of benchmarking provides an opportunity to learn from better performing territories to improve the effectiveness and efficiency of activities in a particular field of interest. Such a field of interest could be road safety. Road safety benchmarking can include several indicators, ranging from performance indicated by crash statistics, to indicators that also account for consequences in costs or the underlying state of the road safety system and relevant organisation and processes at actor level. The structure and culture of a territory is identified as a basic context of road safety performance. This is regarded as important information to use in grouping of territories to get more homogenous or equal and comparable conditions to learn from 'the best in class'.The main aim of this study is to assess the usability of different groupings using the physical structure for benchmarking road safety performance at local territorial level. A traditional grouping of municipalities in the Netherlands was compared with a simple grouping of these municipalities based on their level of urbanisation and an advanced grouping in which more indicators such as differences in demography, growth and road structure were taken into account. As in other studies, urbanisation showed to be the most predominant structural factor for grouping local territories and related to differences in road safety performance. However, if information would be needed for specific target groups, other factors like age and gender distribution or the distribution of the road network can provide valuable additional insight and better homogenous starting points for benchmarking. Especially benchmarking of rural territories may profit from such extra distinctive characteristics. © 2015 Elsevier Ltd.