Arlington, Virginia – The 2011 Cadillac CTS and Infiniti M37/M56 have earned the top rating of “good” in recent roof strength tests, and Top Safety Pick designations, from the U.S. Insurance Institute for Highway Safety (IIHS).

The roof strength tests assess how well vehicles protect occupants in rollover crashes. The 2010 Lexus GS and Audi A6 were rated “acceptable” in the tests, while the 2010 Acura RL was rated “marginal.”

“The test results show that manufacturers are moving quickly to improve the rollover safety of their newest designs,” said IIHS president Adrian Lund.

To earn the “good” rating, a vehicle must have a roof that can withstand a force equal to at least four times the vehicle’s weight.

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