Evaluation of Passenger Vehicle Crashworthiness Using Field Performance Data

Abstract

Both state police and the National Automotive Sampling System/Crashworthiness Data System (NASS/CDS) keep automotive collision statistics to varying levels of detail. Some of these details (e.g., collision relative velocity and driver height and weight) are reported in the NASS/CDS, but not in state databases. This article explores whether these details are confounding factors that would bias conclusions based on analysis of state data. To determine this, a methodology was created to predict overall risk based only on the distribution of possible confounding factors experienced by each manufacturer. Relative impact velocity (Delta-V) and driver height and weight are found not to be true confounding factors. Although the distribution of possible confounding factors varies somewhat among manufacturers, the impact on overall expected risk is minimal, and therefore evaluation of risk based on datasets that do not contain information for Delta-V and driver height and weight appears appropriate. The accuracy of match between police reporting and NASS/CDS was also explored and found consistent across manufacturers. Therefore, inaccuracies between police reports and NASS/CDS should not bias comparisons of risk between manufacturers.