The number of quarter-turns is one widely used metric for rollover severity. However, this metric does not adequately recognize the consequences ofimpacts with fixed objects or with other vehicles that may occur before or during the rollover. Since 1995, the NASS/CDS includes a measurement of the extent of vehicle damage. The database permits rollovers to be groupedaccording to whether or not a harmful crash event preceded or followed the rollover. Groupings can also include the extent of vehicle damage and the number of quarter turns. In NASS/CDS 1995-2003, belted occupants in rollover crashes that were preceded by impacts with fixed or non-fixed objectsand with severe extent of damage had an injury risk three-fold higher than all other rollover groupings. This high risk group requires the extent of damage as a rollover severity metric. When higher injury risk cases withsevere damage were removed, chi square tests showed the significance of the relationship between the number of vehicle inversions and the occupant injury outcome. For the covering abstract see ITRD E141569.
Abstract