In recent years, several major initiatives have been undertaken in Australia to assess relative vehicle occupant protection performance for consumer information. Two of these initiatives undertaken were the New Car Assessment Program (NCAP) and the Driver Protection Ratings (also known as Vehicle Crashworthiness Ratings). The first of these measures the relative occupant safety of current model vehicles by measuring dummy responses in controlled crash testing, following the methods of a similar program undertaken in the United States. The second initiative estimates the relative risk of severe driver injury for individual models of vehicles involved in real crashes by analysing mass crash data using logistic regression techniques.

This paper assesses the relationship between Australian NCAP test results and data from real crashes by comparing the results of crashworthiness ratings to the outcomes of NCAP testing for vehicle models which have been assessed in both programs. Existing crashworthiness ratings based on all crash types have been used in the comparison, as well as crashworthiness ratings derived from crashes of specific types which are thought to be more typical of the crash types the NCAP program claims to represent. Comparison has been made not only with the raw NCAP measures but also with transformations and combinations of these which claim to estimate the probability of severe injury to a vehicle occupant in an NCAP type collision. The effect of vehicle mass in the relationship has also been investigated.

A second stage of the study has examined the relationship between detailed injury data by body region recorded in insurance claim data and the corresponding measurements taken from the various body regions of the crash test dummies in the NCAP procedures.