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Minor roads shouldn’t be left unattended by the police when surveying drink-driving and extensive surveillance is needed during nighttime. These are the main conclusions of a VTI study concerning where and when alcohol-related traffic accidents occur.

The results of the study show that the proportion of alcohol-related fatal accidents of all accidents is about the same on urban and rural roads. Moreover, the proportion of alcohol related accidents is larger on ordinary roads, i.e. two-lane single carriageway with no central reservation, than on other road types on rural state roads.

Within the ordinary roads, alcohol-related accidents are more common on roads with speed limit 60–70 km/h than on roads with speed limit 80-100 km/h and more common on second-class and third-class county roads than on other road categories. A similar pattern is seen in the results for severe accidents, but the differences with respect to speed classes and road categories are not as pronounced as for fatal accidents.

The results also show that 52 per cent of the alcohol related fatal accidents occur between 10 pm and 7 am and that the accident risk is considerably higher during the night than during the day. Drivers under the age of 25 are found in 53 per cent of all alcohol related fatal accidents during the night but only in 14 per cent during the morning and 10 per cent during the afternoon.

The researchers also found that the distribution of drug related fatal accidents on different parts of the road network is more similar to the distribution of accidents with sober drivers than to the distribution of alcohol related accidents.

Pedestrians are the road user category that suffer most injuries caused by ice or snow surface conditions and require medical care. In a VTI study it is demonstrated that pedestrian injury costs, attributed to footway accidents caused by ice and snow, are much higher than the actual winter maintenance cost. Furthermore, approximately 85 per cent of the pedestrians were injured in urban traffic environment. As a result of this, the Swedish Association of Local Authorities and Regions (Salar) endeavours to develop a better understanding for these types of accidents.

The project’s aim was to analyse the importance of the authority or the association responsible for winter maintenance. Did it make a difference to the number of injury accidents if it was the road authority or a property association who managed the winter maintenance? SKL also wanted to know the extent of pedestrian injury costs and relate these to the cost of winter maintenance.

Injured pedestrians data from STRADA healthcare client, in the period 2003-07-01 to 2010-06-30, provided a basis for the analysis. Often, it was only the Kalmar, Skåne, Värmland, Västmanland, Västernorrland and Jämtland regions that were included in the analysis. This was because hospitals from these regions had registered injured pedestrian data in STRADA during the whole analysis period. All injured persons do not necessarily seek hospital care. Treatment may have been obtained from other health care providers. The greater the distance to the hospital, the more likely it is to seek other health care treatment. This means that there is an underestimate of the number of injured.

Winter maintenance costs were obtained for the years 2005 and 2007. The costs related to road authorities’ total winter maintenance costs. Property associations’ maintenance costs for footway surfaces are not included in road authority costs so the costs are for road maintenance. Where the road authority is also responsible for footway surfaces, the cost of maintaining these surfaces is included in the total cost. This means that road authority costs are overestimated.

Using the available data, it has not been possible to determine any differences in the number of injured pedestrians associated to winter maintenance carried out by either road authorities or property associations.

However, it has been demonstrated that pedestrian injury costs, attributed to footway accidents caused by ice and snow, are much higher than the actual winter maintenance cost. In fact, where the road authority maintains pedestrian surfaces, injury costs are at least four times larger than the total cost of winter maintenance.

This means that, in socio-economic terms, it would be worthwhile to invest more resources in footway winter maintenance.

There exist small tendencies which point in the direction of enhanced traffic safety problems with the introduction of extra-long trucks. The purpose of a recent VTI study has been to investigate if the introduction of extra-long and heavy vehicles has an effect on traffic safety on Swedish roads, especially in relation to overtaking.

In the study, traffic safety effects have been measured in terms of road user behavior concerning speed and accelerations and time slots. Road user experiences and heavy truck drivers’ experiences have also been studied. The traffic conflict technique presents how time-to-collision and speed are related to accidents and near accidents. The traffic conflict technique has been used as a starting point for the discussion on how the introduction of extra-long trucks might affect traffic safety.
The report presents four empirical studies: a focus group interview study with heavy truck drivers, an interview study with drivers of extralong trucks, a simulator study and a field study. The simulator study and the field study focus on overtaking.

The purpose with the focus group interview is to investigate if the heavy truck drivers (that do not drive the extra-long trucks) have an opinion on how extra-long vehicles might have an impact on traffic safety. The purpose with the interviews of drivers of extra-long trucks is to grasp the experiences they have of the extra-long trucks. Truck drivers that do not drive extra-long trucks believe that the introduction of extra-long trucks will create a number of traffic safety problems especially in terms of conflicts with ordinary road users. The drivers of extra-long trucks do not experience the problems that ordinary truck drivers predict. The problems they experience can be taken care of with more planning (thinking ahead). They also believe that the traffic sign on the back of the extra-long vehicle has a positive effect. The truck company, working environment and truck equipment are other important aspects mentioned by the drivers of the extra-long vehicles.

The simulator study investigates overtaking situations on a 2+1-road, with extra-long trucks (30 m) and an ordinary truck (18.75 m). The results reveal that the distance from the back of the truck to the point where only one lane exists affects car drivers’ decision to overtake, independently of truck length. If the back of the truck is in the same position, the time slot for a safe overtaking was reduced significantly for extra-long trucks compared to ordinary trucks. Overtaking speed was, however, the same (approxi¬mately 117 km/h).

The field study also studies overtaking situations with an extra-long vehicle (30 m) (with a license to drive on a specific road) and a reference vehicle (24 m), on a 2+1 road and an ordinary 2 lane road. Overtaking vehicles were video recorded with the purpose to measure overtaking behaviour but also in order to be able to contact the road users by telephone. The overtaking personal car drivers did not experience a traffic safety conflict on the road at hand. They did not even remember overtaking an extra-long vehicle. The number of data points was relatively few, especially for the reference vehicle. No significant differences were obtained for overtaking speed or time slots. The overtaking speed was, however, relatively high for both trucks. On the other hand video analyses revealed a small overrepresentation of critical time slots for critical overtakings of the extra-long truck on a normal road, but not for the 2+1 road.

The conclusion is that there exist small tendencies which point in the direction of enhanced traffic safety problems with the introduction of extra-long trucks. The results should, however, not be overinterpreted since the number of data point was few and collected in specific situations and in specific conditions. A conclusion is also that more research is needed. Not to be forgotten is the reduction of the number of trucks on the road if extra-long trucks will be permitted.

Accident rates concerning riders of so-called super-sport motorcycles have been negative in recent years. As part of a strategy for increasing the safety of this group of motorists, the Swedish Motorcyclists Association (SMC) has conducted further training courses for super-sport motorcycle riders since 2004. These voluntary courses consist of four steps, with each step requiring one day of training and education. An incentive for participation is a reduced insurance premium.

VTI has evaluated SMC’s further training courses through two substudies. In the first study, a series of telephone interviews were performed with 29 people who participated in a course during the period July–September 2007. The aim with this qualitative part of the study was to identify what respondents recalled from their participation in the further training course, what they learned from them, and how the aims of the course have been interpreted.

The second study included a follow-up of insurance reported claims (personal and/or property damage) during the period 2007–2009. Two groups were compared: riders of sportmotorcycles who participated in a SMC further training course and those who did not participate in any such course.

From the interview study, it was found that the course structure, i.e. practical exercises interleaved with discussions, received largely positive comments. Some participant did, however, mention the fact that there was a feeling of too little time for rest and for taking in all information before proceeding to the next exercise or discussion. Generally speaking, there was a significant degree of agreement between the aims of the course organisers and the way in which the course participants perceived the aims of the various aspects of the course. Several participants mentioned that they had had much use of what they had learnt from the course. However, riding a motorcycle on public roads was seen as significantly different to riding on a designated track or course, which is why not all aspects of the course were viewed as relevant for the speeds and circumstances that arise in normal traffic conditions. Very few respondents saw any limitations or problems with the contents of the courses. The few suggestions for improvement that were put forward had to do with suggestions to receive greater individual feedback, the use of video cameras, and distribution of printed course material in advance. A potentially positive outcome from a traffic safety viewpoint is the fact that course participation for some respondents had generated insights into how much fun it was to ride a motorcycle on a dedicated track or course. This, in turn, led to many participants voluntarily choosing to minimise the amount of time they spend riding on public roads.

According to the follow-up study of injuries/damages reported to the insurance companies, which was based on 551 matched pairs of course participants versus non-course participants, it was found that no significant difference existed between those who completed the course/courses and those who had not passed SMC further training course. Any traffic safety effect of SMC's courses for sport motorcycle riders was thus not possible to detect by the available data material.

Advantages and disadvantages of different approaches to examine the impact training has on traffic safety are discussed. Through a questionnaire survey, for example, more data on the causes and circumstances of the accident can be obtained.

A workshop initiated by the Traffic Education Group (TUG) at VTI on the theme “Traffic Education - What research is currently conducted in the field today and how do we want the field to develop" was held at VTI in November 2010. TUG was represented by six researchers and six visiting participants from The National Society for Road Safety (NTF), The Swedish National Association of Driving Schools (STR), Trivector Information and The Swedish Transport Agency participated. Initially a lecture was held on the topic of educational trends of today. The presentation focused on the relationships between learning goals, teaching methods and examination. The presentation was followed by a discussion presented in this report.
A lot of research has been conducted in the field but has it been put into practice? Various methods have been tested but not yet used on a larger scale. A proposal about traffic education in the mandatory school has been developed but as the subject will not be compulsory it will probably have very low practical impact. Another important question is who is responsible for financing research in this field. It seems like this task has fallen through the cracks.

The largest part of the discussion was devoted to driving license education and the question was raised whether or not there would be a revision of the whole system initiated by the politicians. The evaluation results of the new syllabus for driving license B indicate that little has changed within the driving license education and the question is whether the driving teachers need more support to transform the curriculum into practical education. The driving schools have to contend with a culture where as few lessons as possible is considered the best (cost and time), which makes it difficult to improve teaching quality.

What research is conducted today and what should be focused on in the future? Formal teaching at driving schools (both theory and practice) has not been scientifically proved to be more efficient than informal private driver training with laymen instructors. Driver instructor's role as interpreter of the course objectives and to translate these into teaching was highlighted as a research area to focus on. The new driver instructor education (with permit and supervising by the new authority Yh-myndigheten, the Swedish National Agency for Higher Vocational Education) was discussed and whether the content and quality of education were deprioritized in relation to the teacher's employability.

Furthermore, there was request for more research on young (mainly male) learner drivers’ brain development (higher order cognitive skills) and the impact of this on their development into safe car drivers (risk perception and self-assessment). What are the motives behind of either a wish to get a license or to refrain from driving was an issue considered valuable to explore further. The importance of the dissemination of research results to teachers and students was also emphasized. Collaboration between branch organizations (and other stake holders) and researchers was consider another important subject.

In Sweden, researchers in traffic education were considered to be few and the need to collaborate and form a network in order to develop traffic education research emerged during the meeting. A number of research questions to explore further were proposed and VTI's coordinating role was highlighted.