Based on a large sample of about 690’000 passenger car accidents in Germany for the years 1998- 2002 this study investigated in full detail the effectiveness of primary safety features in real world accident behaviour in Germany. In a first part of the paper, a statistically sound methodology for such an investigation is presented, which can be applied to large accident databases. Special emphasis is laid on the question of statistical significance. The main statistical tool to be applied is the method of odds ratios in contingency tables.

After a brief review on existing methods and results in this area in the literature (second part) we apply in a third part the presented methodology to the accident material in order to demonstrate the substantial and statistically significant effectiveness of an Electronic Stabilization Program (ESP) in passenger cars in Germany. These results underline the already available results in the literature and are of great relevance because today already more than 60% of the newly registered passenger vehicles in Germany are equipped with ESP. Additionally to the overall effectiveness of ESP the influence under specific accident situations (like specific road conditions, accidents with fatalities and so on) is going to be investigated.

A further part is devoted to other even more recent primary safety features (like brake assist). Here the situation is much more complicated mainly due to the lack of relevant accident cases, e.g. accidents in which cars with brake assist on board are involved. Especially the car-to-pedestrian accidents are going to be investigated in order to see whether a positive effect of the brake assist can be confirmed.

This study was carried through within the Safety Rating Advisory Committee (SARAC) funded by the European Commission.