Up to now quite a few electronic safety functions have been developed in order to successfully increase the safety of passenger in vehicles. Among them are electronic stability control (ESC), brake assists (BAS), lane departure warning systems (LDW) and so on. There exists a short literature on the quantification of the effectiveness of such safety systems on injury outcome or crash severity. As an example the ESC in several studies impressively has been shown to be efficient in avoiding a considerable amount of loss of control or skidding accidents. Nowadays many recently registered vehicles are equipped not only with one but instead with a number of safety functions (socalled safety equipment). The present paper proposes sound statistical methodology in order to investigate the safety benefit of such composite safety equipments (in contrast to a single safety function) in passenger vehicles. It seems obvious that the effectiveness of a specific safety equipment not simply is the additive superposition of the effectiveness of the safety functions of which it consists. For example one may be interested in the additional or incremental effect of an electronic stability control when a brake assist is already on board.

As well we consider secondary safety functions which do not aim at accident avoiding but at injury avoiding or mitigating. Therefore, methodology will be presented to evaluate injury mitigating effectiveness. On this basis it is possible to deal simultaneously with any combination of primary and secondary safety functions.

The developed methodology will be demonstrated on data examples. But the main focus lies on the presentation of methodology.