Automakers, however, argue that rollovers are relatively infrequent and that S.U.V.'s are safer than cars in other types of crashes.
With years of progress in engines, navigation and control systems, and with better training and procedures, many of the types of crashes that were once common are now unusual.
The increase of nearly 1,000 in annual rollover deaths in sport utilities since 1993 has been mirrored by virtually identical increases in the annual number of people killed in rollovers over all, and the annual number of people killed by all types of crashes.
The overall death rate for Explorer occupants in all types of crashes is 24percentt lower than the overall rate for other mid-size sport utilities, and is comparable to death rates for cars because Explorer occupants fare well in collisions with other vehicles, Mr. Grush said.
It also identifies traffic patterns associated with different types of crashes and explains crash phenomena thereby.
More than half of all crashes were ROR, with animal-vehicle collisions, and rear end crashes being the next most common types of crashes, respectively.
It is well established that rollover crashes are associated with a higher risk of serious injury and death than other types of crashes.
The published work estimated the reduction of selected types of crashes (typically, median crossover collisions) or the overall effect of barriers on crash severity.
