Drivers of vehicles that do poorly in the side-impact crash tests conducted by the Insurance Institute for Highway Safety are three times as likely to die in a real-world left-side crash than drivers of vehicles that perform well, a an IIHS analysis reports.
"Vehicles with good side ratings provide occupants with far more protection than vehicles that do poorly in our test," says institute chief research officer David Zuby.
The IIHS says studies of frontal crashes have shown similar results.
Side-impact crashes accounted for 27 per cent of passenger vehicle occupant deaths in the United States in 2009, notes the IIHS. Such crashes, says the institute, can be particularly deadly because the sides of vehicles have relatively little space to absorb energy and shield occupants.
The institute's side crash test differs from the U.S. Government's in that the IIHS uses an SUV-like barrier, while the National Highway Traffic Safety Administration uses a lower barrier designed to mimic a passenger car.
There is also a difference in crash test dummies. Until recently, both dummies used in the U.S. government's side barrier test represented average-size men; the institute's side test has always used dummies representing small women or 12-year-old children, which naturally makes scoring well more difficult.