The Insurance Institute for Highway Safety (IIHS) awarded a new safety recognition level, Top Safety Pick+, to 13 cars from the 2013-MY.

To earn this new safety recognition level, all these vehicles have earned "good" or "acceptable" scores in IIHS’ new small overlap frontal crash test and top ratings in IIHS’ other safety tests.

The winners include:

• Acura TL

• Dodge Avenger

• Chrysler 200 four-door

• Ford Fusion

• Honda Accord two-door and four-door

• Kia Optima

• Nissan Altima four-door

• Subaru Legacy and Outback

• Suzuki Kizashi

• Volkswagen Passat

• Volvo S60

IIHS introduced the new small overlap frontal crash test in 2012. The test is designed to simulate what occurs when a car’s front corner collides with another vehicle or object.

In the actual test, a quarter of the vehicle’s front end, on the driver’s side, collides with a five-foot-tall rigid barrier at 40 mph. IIHS belts a Hybrid III male crash test dummy into the driver’s seat. The organization said it first evaluated luxury mid-size cars and then mid-size moderately priced cars.

IIHS plans to release results for small SUVs in the spring.

According to IIHS, a number of automakers made changes to their vehicles to improve safety. Ford and Nissan made structural changes to 2013 models in production. Subaru and Volkswagen changed the airbag control modules on the production line so the vehicles’ side-curtain airbags would deploy so they provide additional head protection. Honda engineered its two Accord models to do well in the test as well, IIHS said.

In general, IIHS has tightened its Top Safety Pick criteria since it introduced its tests in 2006. IIHs made "good" rear crash tests results and electronic stability control availability requirements in 2007. Stability control is no longer a distinguishing feature, though, since federal rules require that feature for 2012 and later models. Good roof strength became an evaluation metric for 2010-MY vehicles.

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