Tests undertaken by America’s Insurance Institute for Highway Safety (IIHS) reveal that a number of popular 2008-model midsized sedans have shown marked improvements in their side-impact safety ratings. However, the news isn't all good as the majority of cars tested saw only marginal improvements in their rear-crash results, a segment which costs the insurance industry around $8.5 billion every year.

The models tested included the Chevy Malibu, Dodge Avenger, Infiniti G35, Kia Optima, Mitsubishi Galant, Saturn Aura and Nissan Altima and all were new 2008 models. Speaking with The Detroit News, a spokesman from the IIHS noted that the most impressive aspect of the test results was the improvement in side-impact results, representing "a huge change from just four years ago."

The improvement in side-impact safety has been attributed to side airbags becoming standard on most new models and the agreement from carmakers to install head-protecting side air bags as standard by 2010, which some have already complied with. Additionally, torso-protecting airbags will be required by 2013 to further improve safety. Recent statistics have shown that 28% of all motor vehicle fatalities occur during side-impact crashes, meaning the new standard airbags can't come soon enough.

While side-impact ratings were much improved, rear-protection remained poor except for Kia’s Optima, which was rated safer than its peers. Four of the seven vehicles tested by the institute - the Malibu, Aura, G35 and Altima - all received marginal ratings in rear crash tests, while the Mitsubishi Galant was rated poor. The Dodge Avenger and its Chrysler Sebring sibling, meanwhile, were rated adequate for rear protection.