ARLINGTON, VA – The Lexus GS, a large luxury car redesigned for the 2013 model year, has drawn the Insurance Institute for Highway Safety’s top award for good performance in front, side, rollover and rear-impact crash evaluations.

The GS is the third Lexus to qualify for Top Safety Pick since the IIHS expanded the award criteria in 2010 by requiring good performance in a roof strength test that assesses rollover protection. The other models are the RX, a midsize luxury SUV, and the CT 200h, a hybrid small car.

To measure roof strength, a metal plate is pushed against one corner of a vehicle's roof at a constant speed. The maximum force sustained by the roof before 5 inches of crush is compared to the vehicle's weight to find the strength-to-weight ratio. This is a good indication of vehicle structural protection in rollover crashes, the IIHS said.

The roof of the GS withstood a force equal to 4.88 times the vehicle's weight. Vehicles with a strength-to-weight ratio of 4 or better earn a "good" rating.