The COST Action operates under the acronym “HOPE” (Helmet OPtimization in Europe) with the goals to: - Increase scientific knowledge about bicycle helmets in regards to traffic safety. - To disseminate this knowledge to stakeholders, including cyclists, legislators, manufacturers, and the scientific community. - To stimulate international collaboration in de field of bicycle traffic safety and helmets. There are 4 working groups, which have to disseminate their results within a summery report. Working group WG1 carried out accident analysis and carried out field studies to follow their tasks for optimazing the bicycle helmet: 1. Development of an Pan European Database on In-depth accident results on Injury Statistics 2. Development of acceptance criteria and finding problems in bicycle helmet use. As partners of this network within WG 1 the Univerities Hannover (Germany), Pavia (Italy), Heraklion and Athens (Greece), Lisbon (Portugal) as well as the Finnish Motor Insures Centre Helsinki and AGU Zürich (Switzerland) worked together in one working group (WG 1) dealing with 3 different topics: # A. Report on injury situation of bicyclists in traffic accidents on a European level with focus on helmet usage # B. In-depth Accident analysis of head injuries and the effectiveness of the bicycle helmet in Real Accident Situations # C. Habits of helmet usage of cyclists by means of a reporting problems in comfort, temperature and climatization reported by questionnaire requests # D. Identifying the influences of the seating geometry, the posture and the helmet postion of cyclists on safety aspects The statistical data on bicycle accidents in Europe was analysed by using the bicycle basic-factsheets based on CARE data and by using data provided be the participants of WG1. It can be seen that the cyclist fatalities were decreasing between the years 2001 and 2010 in Europe. However there is a difference between the European countries, as such the fatality (fatalities per million inhabitants) varies from 1 (Ireland) to over 8 fatalities per million inhabitants in Netherlands, Romania and Hungary. Furthermore in Denmark for example over 75% of cyclist fatalities occurred in urban areas, while only 26% occurred in urban areas in Spain. Based on the national statistical data provided by the COST partners the injury situation of was compared and again revealed major differences between the countries concerning the share of injured bicyclists of all injured traffic participants. It has to noted that comparability here is difficult due to different definitions concerning slight and severe injuries among the different countries. The reported helmet using rate in the different European countries varies from 3% in Italy to over 50% in Norway, if looking to all age groups of bicyclists. The highest rate can be seen for children, as in some countries like Austria or Sweden a mendatory use of the helmet is established for children. According to the EU Injury Database IDB 32% of road accident casualties recorded in the database were admitted to the hospital overall, while this was the case only for 23% for cyclists. Cyclists especially suffered from fractures and open wounds more frequently than other road users. An overview over the bicycle helmet legislation in different countries worldwide shows that for many countries no information was available which often means that no helmet wearing requirements are in place. In some countries there is a mandatory helmet use for certain age groups (mostly children). Some countries however state that there is no intention of introducing a mandatory helmet law, based partly on international views that a mandatory requirement may lead to a reduction in cycling activities. A study conducted on bicycling and alcohol use and aspects of helmet use with German in-depth data revealed that riding under the influence of alcohol does have an influence on the proportion of guilt for causing the accident but also on the helmet usage rates. Cyclists which did not wear a helmet were more likely to have consumed alcohol. Furthermore cyclists who were not responsible for the collision were less likely to have consumed alcohol than those who were partially responsible for the accident. Cyclists involved in collisions with another vehicle, motorised or not, had a lower risk of suffering a head injury compared with those involved in single vehicle accidents. Accident investigation of e-bikers in Switzerland showed that most e-bikers who were involved in an accident were older than most accident-involved bicyclists and the analysis of the type of accident revealed e-bikers to be involved in single accidents most frequently. In Switzerland 52% of the accident-involved e-bikers wore helmets while bicyclists wore helmets less frequently. It was also concluded that bicyclists and e-bikers aged 40+ are at higher risk of sustaining severe injuries than bicyclists and e-bikers aged 0-39 An accident analysis of head injuries using the database of the German in-depth Accident Study (GIDAS) revealed that wearing rate of bicycle helmets recorded in the accidents which occurred between 2000 and 2012 can be viewed quite positively on the one hand in that the numbers of wearers are rising in Germany, which signals a growing acceptance of helmets on the side of the bicyclists, but the current rate of slightly over 10% is still extremely low. Furthermore the study of GIDAS data shows a significant benefit of helmets on the resulting injury frequency and severity of head injuries for bicyclists involved in accidents. In doing so a visible protection against serious head injuries was found: skull fractures, severe brain injuries and skull base fractures alike, all appear to be less common when using a helmet. Virtually no injury reduction resulted for facial fractures (2.6% versus 2.7%) as this is not the region of the head, which is well protected by cycling helmets. Scientific literature also fails to provide evidence of a protective effect in this case. For instance a protective effect was detected for the upper and middle part of the face, but not for the lower facial area, which, due to the small number of cases and a non-significant but trend-wise interpretable statistical test, is also confirmed by this study. A bicycle helmet can be considered particularly effective for older adults. This was particularly evident for the age groups of 50+ years, where a significant increase of severe head injuries occurred in the group of riders without a helmet. Especially for older bicyclists, biomechanics result in higher injury severities of bony and brain structures that can be protected effectively by a helmet. These persons should increasingly protect themselves against head injuries by wearing a helmet, as it is known that the biomechanical load limits for older persons are significantly lower than those of younger ones. Educational campaigns and possibly even legal demands seem to be an appropriate measure to increase helmet wearing rates and thus to reduce the head-injury-severity in this context. It should be mentioned as well that about 40% of cyclists without a helmet, who were involved in traffic accidents resulting in personal injury, suffered head injuries. Injuries outside the protection area of a helmet in the form of facial injuries are relevant only as serious injuries in the form of facial fractures. However, it can be gleaned from the analysis in this study that helmets offer a small benefit as injuries to the upper part of the face are reduced, due to the protruding frontal part of helmet structure. After all, head injuries alone without any other injured body area account for 13% of the most severe injuries in cyclists. In 23% of the cases, the heads of the cyclists were amongst the most severely injured body parts. An optimization of the current models of helmets seems appropriate. For instance, the study showed for the sides and the edges of the helmet, in particular considering shock absorbing aspects, a potential for extending the protection zone currently identified in the existing standard CEN EN 1078. This appears even more important when taking into account that impacts at the side of the helmet seem to result in higher injury severities than impacts at the top. Although the accidents proved a shock absorbing effect for edges at the sides of the helmet, all helmet materials cracked there and resulted in the described injury reduction due to energy absorption. Enlarging the protection zone and optimizing the helmet design in this area, would result in a further optimization by accident related adaptation of the test requirements of CEN EN 1078. The different impact conditions of the head were analyzed regarding the surface of the impact zone. It could be established that 88.3% of all head impacts happened on a flat surface while 11.7% happened on an edgy surface. The majority of the edgy impacts occurred from impacts against edgy parts from cars and trucks. To analyze the helmet usage practice of bicyclists in Europe Working group 1 developed a questionnaire to collect relevant information by means of a field study carried out in the years 2010 to 2014. It might be regarded as a limitation that the 994 answered questionnaires which were available for the analysis of the helmet usage are not representative for the cycling situation in Europe because the interviewed riders could not be randomly picked at random places during random times and interviews were only conducted in 5 different countries. However the study revealed that the helmet wearing rates seem to depend on the country and the type of bicycle used. As such riders of racing bikes seem to use helmets more often than riders of other types of bicycles and in Finland generally more cyclists use helmets than in the other participating countries. In general bicycle riders with or without a helmet thought that riding a bicycle is more dangerous than driving a car or walking. The reason for not wearing a helmet was mostly just carelessness, short distance, high temperatures or the need to carry around a helmet at the destination, while the most common reason for wearing a helmet was the feeling of safety. So the riders are aware of the risk of riding a bicycle and believe that the helmet does have a potential for protection but carelessness and a missing solution where to leave the helmet at the destination often leads to not wearing a helmet. Furthermore the questionnaire revealed that the helmet usage rarely leads to hearing problems or problems concerning the vision such as a narrowed field of vision in most countries. However some riders complained about unpleasant symptoms after using the helmet such as headaches. The fact that using the helmet makes you sweat more was also stated often as an unpleasant symptom. Asked about previous bicycle accidents, those riders that had been in an accident before reported that it had mostly been a single vehicle accident (48%) where they fell off the bicycle for different reasons or a collision with a car (26%). Collisions with other traffic participants or with objects were rarely reported. Here the main impact zones of the helmet were stated to be the sides of the helmet and the front. Hence according to this analysis the main function of the helmet should be the protection against injuries at the side of the head and at the face when hitting the ground. In the scope of a second field study the methodology of taking pictures of bicyclists to evaluate the seating posture was developed by Working Group 1. It has proven to be a viable technique to identify general angles describing the seating positions, even though it is not possible to identify the exact angles in every case. Together with the estimation of the age group to which the rider belongs it was possible to analyse the seating position with respect to the helmet usage and the different age groups. The incline of the line between the handle bar and the seat describes if and how much the handle bar is above the seat. This measure is significantly influenced by the type of bicycle: While racing bikes often have a handle bar which is below the level of the seat, this is not the case in mountain bikes or city bikes. The posture of the upper body (sitting decline) is influenced by the type of bicycle as well and therefore the analysis of the head posture was conducted only for city bikes (the most common group of bicycles in the sample). In general the analysis of the photos revealed that the age of the rider has no significant influence on the head posture. Interestingly the helmet usage seem to have an influence on the head posture: Riders with a helmet held their head slightly lower than riders without a helmet. The vertical vision limit due to the helmet is determined by the front rim of the helmet (mostly the sun shade). Typical values here range from just above 0° (horizontal line from the eye to the sun shade) to 75° upwards. Here the elderly riders tend to have a slightly enhanced limit of vision upwards, meaning a lower vision angle. As the age of the rider had no influence on the head position, this enhanced vertical vision limit of older riders could be explained by those riders wearing the helmet more downwards towards the face. The work carried out within working group WG 1 lead to some remarkable results in summary. In general the potential of bicycle helmets appears to be not yet fully exhausted. In particular, a helmet may have additional benefits as device implemented with additional techniques for example as integration of GPS for driver assistance systems. With such development the bicyclist can be integrated in the potential of avoidance strategies of accidents by assistant systems respectively intelligent traffic systems ITS. A helmet can also contribute to the visibility of cyclists and it can certainly also increase the security awareness of the cyclist and thus help to prevent injuries. However, studies have also revealed that helmets can result in a changed behavior of cyclists, which counterbalance the safety effect of the helmet. In this area additional research is required, to transfer the proven benefits of a bicycle helmet into an effective usage in the real world. The analyses of both field studies produced interesting results. The case numbers were sufficient to display tendencies. For more significant analysis or more in-depth analysis, e.g. for comparing countries, more cases would be necessary. Based on these different studies of literature, in-depth-investigations of accidents and field studies on driving behaviors and helmet postures as well as questionnaire requests, problems in helmet usage could be identified and the effectiveness of the helmet protection could be established. The effectiveness of bicycle helmets in accidents can be established however, there are also studies that question the effectiveness of bicycle helmets in accidents. The effectiveness of bicycle helmets in literature is often discussed in conjunction with mandatory helmet use, for that reason there are a few studies that specifically show the effectiveness of the helmet in relation to injuries sustained and a scientific assessment of the protective potential of helmets in view of certain injury patterns to the head. In particular in Germany, there are few studies on the effectiveness of bicycle helmets, since as yet there is little helmet use, which does not permit statistical comparisons of wearers of helmets with those without a helmet and therefore are mostly exploratory and were conducted using single randomization, for which usually no control groups were available. Only recently have results for the effectiveness of helmets appeared based on accident analyzes for Germany. A study by the insurance company Allianz Versicherung published in 2013, which advocates the use of bicycle helmets noting that seniors constitute 51 % of all pedestrian and cyclists fatalities, one third of all bicycle accidents without involving third parties are falls and the number of unreported cases is very high, which means they are not included in any of the accident statistics. A study by the Universitätsklinik Münster published in 2012 also points that way. Therefore a higher helmet effectiveness can be assumed than given by the statistics. For many European countries no data on helmet use exsist. Helmet use should be integrated in the official data collection by the police in all European countries. The potential of bicycle helmets appears to be not yet fully exhausted. In particular, a helmet may have additional benefits and give opportunity for an implementation of driver assistance systems. A helmet can also contribute to the visibility of cyclists and it can certainly also increase the security awareness of the cyclist and thus help to prevent injuries. However, studies have also revealed that helmets can result in a changed behavior of cyclists, which counterbalance the safety effect of the helmet. In this area additional research is required, to transfer the proven benefits of a bicycle helmet into an effective usage in the real world. Helmets have to be optimized by modification of the outer design. It could be pointed out in this study that the impact conditions are not fully covered by the CEN Standard EN 1078. Especially the lateral side is a major impact area, the helmet design have to covered this by extend the lateral proection zone. Some of the most common health problems and annoyances associated with cycling can be attributed to poor bicycle fit and wrong cycling posture. These problems are usually observed at three areas of the human body, namely the neck, the lower back and the lower limbs and most often the knee. Recommendations from the study of WG 1 # increase the helmet use in all countries in Europe (helmet is effective against head injuries); # reporting about helmet use from all countries in Europe (need more information about cycling and helmet use, monditoring of data from hospitals, government and infrastructure, coding of MAIS3+); # integration of data on injuries into police reports for statistical issues; # optimization of helmet design on the lateral part of the helme;t # modification of the helmet standard within CEN 1078 for protection zone and impact conditions conformity to real accidents; # finding improvements for helmet design and helmet wearing for different kind of bicycles (citybikes, racing-bikes, mountain-bikes, e-bikes); # Improvements for best helmet position on the head for high safety. (Author/publisher)
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