Injury protection and accident causation parameters for vulnerable road users based on German In-Depth Accident Study GIDAS.

Within a study of accident data from GIDAS (German In-Depth Accident Study), vulnerable road users are investigated regarding injury risk in traffic accidents. GIDAS is the largest in-depth accident study in Germany. Due to a well-defined sampling plan, representativeness with respect to the federal statistics is also guaranteed. A hierarchical system ACASS (Accident Causation Analysis with Seven Steps) was developed in GIDAS, describing the human causation factors in a chronological sequence. The accordingly classified causation factors - derived from the systematic of the analysis of human accident causes ("7 steps") - can be used to describe the influence of accident causes on the injury outcome. The bases of the study are accident documentations over ten years from 1999 to 2008 with 8204 vulnerable road users (VRU), of which 3 different groups were selected as pedestrians n=2041, motorcyclists n=2199 and bicyclists n=3964, and analyzed on collisions with cars and trucks as well as vulnerable road users alone. The paper will give a description of the injury pattern and injury mechanisms of accidents. The injury frequencies and severities are pointed out considering different types of VRU and protective measures of helmet and clothes of the human body. The impact points are demonstrated on the car, following to conclusion of protective measures on the vehicle. Existing standards of protection devices as well as interdisciplinary research, including accident and injury statistics, are described. With this paper, a summarization of the existing possibilities on protective measures for pedestrians, bicyclists and motorcyclists is given and discussed by comparison of all three groups of vulnerable road users. Also the relevance of special impact situations and accident causes mainly responsible for severe injuries are pointed out, given the new orientation of research for the avoidance and reduction of accident patterns.

Otte D ，Jänsch M ，Haasper C 《-》

[Knee injuries of vulnerable road users in road traffic].

Haasper C ，Otte D ，Knobloch K ，Zeichen J ，Krettek C ，Richter M ... -  《UNFALLCHIRURG》

Injury incidence rates of cyclists compared to pedestrians, car occupants and powered two-wheeler riders, using a medical registry and mobility data, Rhône County, France.

In France, the bicycle's modal share is stabilizing after a decline; in some of France's major cities, it has even increased since the 1990s. It is hence relevant to improve the knowledge of the injury risk associated with cycling, compared with other means of transport such as car, walking and powered two-wheeler (PTW) riding. The injury incidence rates were estimated by the ratio between accident data and mobility (exposure) data. Two accident data sources were used: police data and hospital-based data (outpatients and inpatients) from the Rhône road trauma Registry. This provides four injury categories: all-injury, hospitalization, serious-injury and fatal-injury. Exposure data were estimated from a regional household travel survey (RTS), using three measures of mobility: number of trips, distance traveled and time spent traveling. The survey was carried out from November 2005 to April 2006, on weekdays, outside school and public holidays; this seasonality was corrected using the 2007-2008 national household travel survey (NTS) that covered an entire year. Only information involving accidents and trips in, and residents of, the Rhône County (1.6 million inhabitants, including the city Lyon) were included in our study. Trends of injury rates were also evaluated in Greater Lyon, using previous travel surveys. The PTW riders had the highest all-injury, hospitalization, serious-injury and fatal-injury rates, followed by cyclists, and lastly by pedestrians and car occupants. The rates between men and women seemed similar among pedestrians and among car occupants. For car occupants, pedestrians and cyclists, the age group 18-25 years had higher all-injury rate compared with the age group 25-65 years. On the contrary, the age group≥65 years seemed to have higher hospitalization and serious-injury rates, compared with the age group 25-65 years. For cyclists, the injury rates seemed higher in non-dense areas than in dense areas. Between 1996-1997 and 2005-2006 and with regards to time spent traveling, the all-injury, serious-injury and fatal-injury rates seemed to have decreased for car occupants and cyclists. The higher risk for PTW riders is confirmed and quantified; it is very high. Decrease in injury rates seems more marked for cyclists; this may indicate the "safety in numbers" effect. Countermeasures for improving road safety could be implemented, especially for vulnerable road user types. However, they will not be sufficient to fill in the gap between the much higher risk for PTW riders and that of car occupants. Exposure-based injury rates can be a tool for monitoring and evaluating the effectiveness of policies and programs, and for comparisons between countries.

Blaizot S ，Papon F ，Haddak MM ，Amoros E ... -  《-》

Alcohol consumption, helmet use and head trauma in cycling collisions in Germany.

Cycling, being easy, inexpensive and healthy, is becoming one of the most popular means of transport. Cyclists, however, are among the most vulnerable road users in traffic collisions. The aims of this study were to establish which cyclist and cycling accident characteristics are associated with alcohol consumption and helmet use in Germany and to identify risk factors related to head trauma sustained in cycling accidents. The source used for the present analysis was the database of the German in-depth accident study (GIDAS). All cyclists who had been involved in a road accident between 2000 and 2010 and submitted to an alcohol test were selected. Logistic regression analyses were carried out to evaluate various aspects: alcohol consumption, helmet use, head trauma, and cyclist/accident characteristics. Female riders were less likely to have consumed alcohol (OR=0.23, 95% CI: 0.08-0.66); cyclists who did not wear a helmet were more likely to have consumed alcohol (OR=2.41, 95% CI: 1.08-5.38); cyclists who were not responsible for the collision were less likely to have consumed alcohol than those who were partially responsible for the accident (OR=0.22, 95% CI: 0.08-0.61). 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 (OR=0.27, 95% CI: 0.12-0.62, and OR=0.08, 95% CI: 0.03-0.22, respectively). The prevention or limiting of alcohol consumption among cyclists and the corresponding testing of cyclists must be improved. Training initiatives on helmet protection should be encouraged.

Orsi C ，Ferraro OE ，Montomoli C ，Otte D ，Morandi A ... -  《-》

Causation mechanisms in car-to-vulnerable road user crashes: implications for active safety systems.

Vulnerable road users (VRUs), such as pedestrians and bicyclists, are often involved in crashes with passenger cars. One way to prevent these crashes is to deploy active safety systems that support the car drivers and/or VRUs. However, to develop such systems, a thorough understanding of crash causation mechanisms is required. The aim of this study is to identify crash causation mechanisms from the perspective of the VRUs, and to explore the implications of these mechanisms for the development of active safety systems. Data originate from the European project SafetyNet, where 995 crashes were in-depth investigated using the SafetyNet Accident Causation System (SNACS). To limit the scope, this study analyzed only intersection crashes involving VRUs. A total of 56 VRU crashes were aggregated. Results suggest that, while 30% of the VRUs did not see the conflict car due to visual obstructions in the traffic environment, 70% of the VRUs saw the car before the collision, but still misunderstood the traffic situation and/or made an inadequate plan of action. An important implication that follows from this is that, while detection of cars is clearly an issue that needs to be addressed, it is even more important to help the VRUs to correctly understand traffic situation (e.g., does the driver intend to slow down, and if s/he does, is it to let the VRU cross or for some other reason?). The former issue suggests a role for various cooperative active safety systems, as the obstacles are generally impenetrable with regular sensors. The latter issue is less straightforward. While various systems can be proposed, such as providing gap size estimation and reducing the car speed variability, the functional merits of each such a system need to be further investigated.

Habibovic A ，Davidsson J 《-》