Abstract
This study describes the calculation of updated ratings that measure the relative safety of vehicles in preventing severe injury to people involved in crashes. Three different aspects of secondary safety are examined: crashworthiness which focuses on drivers of the rated vehicle; aggressivity which focuses on drivers of other vehicles and unprotected road users such as pedestrians, cyclists and motorcyclists colliding with the rated vehicle; and total secondary safety which examines the combined crashworthiness and aggressivity performance of the rated vehicle. Updated ratings for 1982-2021 model vehicles were estimated based on data on crashes in Victoria, New South Wales, Queensland, Western Australia, New Zealand and South Australia during 1987-2021.Crashworthiness estimates and their associated confidence limits were obtained for 824 vehicle models classified into ten market groups. Aggressivity rating estimates and their associated confidence limits were obtained for 743 vehicle models. The total secondary safety index estimates and their associated confidence limits were obtained for 890 vehicle models classified into ten market groups. This update of the vehicle safety ratings includes estimation of a vehicle primary safety (crash avoidance) index reflecting the fitment of key proven crash avoidance technologies including electronic stability control, roll stability control, autonomous emergency braking, lane keep assist and reversing sensors and cameras.A method for calculating the Overall Safety rating, which measures the combined crashworthiness and aggressivity performance reflecting the relevant importance of each attribute in determining overall injury outcomes in a crash, is also described. The rating presentation classifies vehicles according to where their rating lies across equal quintiles.The relationship between vehicle crashworthiness and the year of manufacture of Australian passenger and light commercial vehicles manufactured from 1964 to 2021 was also investigated. Trends were examined by year of manufacture both for the fleet as a whole and by market group for vehicles manufactured from 1982 to 2021.The results of this report are based on a number of assumptions and warrant a number of qualifications that should be noted.