Vehicle safety ratings estimated from police reported crash data: 2006 update Australian and New Zealand crashes during 1987-2004

Monash University Accident Research Centre - Report #248 [2006]

Authors: Newstead, S.V., Cameron, M.H. and Watson, L.M.

Full report in .pdf format [1.0 MB]

Abstract:

Crashworthiness ratings measure the relative safety of vehicles in preventing severe injury to their own drivers in crashes whilst aggressivity ratings measure the serious injury risk vehicles pose to drivers of other vehicles and unprotected road users such as pedestrians, cyclists and motorcyclists. Updated crashworthiness ratings and aggressivity ratings for 1982-2004 model vehicles were estimated based on data on crashes in Victoria and New South Wales during 1987-2004 and in Queensland, Western Australia and New Zealand during 1991-2004. Both crashworthiness and aggressivity were measured by a combination of injury severity (the risk of death or serious injury given an injury was sustained) and injury risk (the risk of injury given crash involvement). The ratings were adjusted for the sex and age of the person whose injury outcome was being measured, speed limit at the crash location, the number of vehicles involved where relevant, the jurisdiction in which the crash occurred and the year in which the crash occurred. These factors were strongly related to injury risk and/or severity. In addition to the above factors the aggressivity rating was also adjusted for the type of other road user impacted as this factor was strongly related to injury severity and varied between vehicle models. The ratings estimate the risk of being killed or admitted to hospital when involved in a crash, to a degree of accuracy represented by the confidence limits of the rating in each case.

Crashworthiness estimates and their associated confidence limits were obtained for 305 vehicle models classified into 12 market groups. They were sufficiently sensitive that they were able to identify 159 models of passenger cars, four wheel drive vehicles, passenger vans and light commercial vehicles that have superior or inferior crashworthiness characteristics compared with the average vehicle. Aggressivity rating estimates and their associated confidence limits were obtained for 284 vehicle models and were sufficiently sensitive that they were able to identify 129 models of passenger cars, four wheel drive vehicles, passenger vans and light commercial vehicles that have superior or inferior aggressivity characteristics compared with the average vehicle.

The relationship between vehicle crashworthiness and the year of manufacture of Australian passenger and light commercial vehicles manufactured from 1964 to 2004 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 2004. Also investigated was the relationship between vehicle crashworthiness and both the year of manufacture and the year of first registration in New Zealand light passenger vehicles manufactured from 1964 to 2004 and crashing during 1991 to 2004. The latter analysis was aimed at assessing crashworthiness trends in the fleet of used imported vehicles in New Zealand whilst the former examined trends in the fleet as a whole.

The results of this report are based on a number of assumptions and warrant a number of qualifications that should be noted.

Sponsoring organisations - Road Traffic Authority of NSW, Royal Automobile Club of Victoria Ltd, NRMA Ltd, VicRoads, Royal Automobile Club of Western Australia Ltd, Transport Accident Commission and Land Transport New Zealand, the Road Safety Council of Western Australia, the New Zealand Automobile Association and by a grant from the Australian Transport Safety Bureau