Promoting safety using retrospective large databases

Abstract

Large-scale accident studies are an indispensable tool to idente the focal points of crash occurrence and the benefits of active and passive safety systems. This report describes the requirements on data quality and presents results of retrospective large-scale studies concerning collision types in real-world accidents, effect of safety systems and possibility and limits of car safety assessment. Large-scale studies of the German Motor Insurers (GDV), covering close to 20,000 accidents, indicate that 6 crash configurations cover the majority of fatal car crashes. A weighting procedure of car-to-car and single car crashes, integrated assessment of collision types is described. The effectiveness of safety systems is a typical research field of large-scale accident studies. An analysis of 249 airbag cases showed that driver airbags reduce Serious/fatal injuries by more than 40% compared with seat belt only cases. For passenger airbags, up to now, no clear evidence of injury reduction has been found in general, but their effect in very serious front crashes is thought to be unquestionable. Accident studies with children in cars showed a seven times lower risk for fatal and serious injuries to restrained than to unrestrained children. But Child Restraint Systems (CRS) could be still more efficient. In a study carried out on CRS, it was noticed that serious misuse was found in 33% of cases, misuse including minor faults amounted to 63%. A further study, based on 150 persons, showed that a standardised rigid connection between CRS and vehicle, the ISOFIX-system, would reduce misuse by at least a factor ten. Large-scale studies are a pre-requisite for safety rating systems, which promote the consumer's interest in car safety. In a GDV-research project, the experience with existing safety rating systems has been analysed. Calculations based on uniform accident material, selected from the GDV database, showed that ranking differences mainly relate to the procedure of the rating systems and less to different traffic circumstances in different countries.