Several midsize cars have made improvements in protecting motorists in side crashes because of improvements in design and adding side airbags, the insurance industry reports.

The Insurance Institute for Highway Safety crash test results gave top scores in front-end and side-impact crashes to the 2008 Chevrolet Malibu, Saturn Aura, Dodge Avenger, Nissan Altima, Infiniti G35, and Mitsubishi Galant. The 2008 Kia Optima received the highest score in front-end tests and the second highest score in the side test.

Frontal crash tests simulate a 40 mph crash and its effect on the driver. Side crash simulations show what would happen if the vehicle was struck in the side by a sport-utility vehicle at 31 mph.

10 similar vehicles tested in 2004 without side air bags received the lowest rating of “poor” in the side tests. Only past generations of the Honda Accord, Toyota Camry, and Chevrolet Malibu received the top score in 2004 when they were tested with side air bags. The air bags were largely optional in 2004 but are standard in all seven of the 2008 vehicles the institute reviewed.

In rear end testing in which a 20 mph crash and its effect on the driver are simulated, the results were mixed. The Optima was the only vehicle tested to receive a top rating, followed by the Avenger, which received the second highest score of “acceptable.”

The G35, Altima, Malibu, and Aura received the second-lowest score of “marginal” while the Galant received the lowest rating of “poor.”

Rear crashes can lead to neck injuries in which there are about 2 million insurance claims a year, costing at least $8.5 billion.

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