ARLINGTON, VA --- The Ford Focus and Volvo C30 excelled in recent crash tests by the Insurance Institute for Highway Safety, earning the vehicles the coveted Top Safety Pick designation. 

The IIHS's latest series of tests focused on two-door vehicles. To evaluate the extent to which automakers are extending crashworthiness improvements to two-door cars, the institute conducted front, side and rear tests of 2009 coupes. Those tested were the Chevrolet Cobalt, Ford Focus, Honda Civic and Scion tC, all small models, plus the midsize Volvo C30.

"We're often asked about the crash test performance of two-door cars," said David Zuby, institute senior vice president for vehicle research. "Design and structural differences mean we can't automatically apply our test results of four-door cars to two-door versions of the same models. We decided to do these tests to see how the two-doors stack up in protecting people in the three most common kinds of crashes." 

The institute rates vehicles "good," "acceptable," "marginal," or "poor," based on performance in front and side crash tests. The third test measures how well vehicle seats and head restraints protect people against neck injury in low-speed rear crashes. 

"Overall, the results for two-door cars are good news," Zuby said. "All but one earn 'good' ratings in our frontal offset test. Only two of the five earn this rating for protection in side crashes, but none of the five earns anything less than an 'acceptable' rating. This is pretty good, considering how demanding the side test is. It simulates being struck by a pickup or SUV." 

Zuby added that "all five cars in this group, from relatively inexpensive to moderately priced, have head-protecting side airbags as standard equipment. In 2003 automakers pledged to voluntarily put side airbags in their vehicles as standard equipment by the 2010 model year. They're making good on this pledge." 

Earning "good" ratings in all three of the institute's tests and equipped with optional electronic stability control, the Focus qualifies as a 2009 Top Safety Pick among small cars. Also earning this award is the midsize Volvo C30. Seven small cars and 10 midsize moderately priced models have now earned the award, the institute's top safety designation. 

"Choosing a vehicle that provides top-notch crash protection is easier than ever," Zuby said.

Among the five car models the institute recently tested, four earned the top rating of "good" in the 40 mph frontal offset test. The Scion tC was rated "acceptable." 

The tC's structure held up well, but overall performance wasn't as good as the other cars, the IIHS said. Forces recorded on the driver dummy indicated that an injury to the lower right leg would be possible, and a high head acceleration occurred when the dummy's head bottomed out the airbag. 

The tC is unique in this group for having a separate airbag in the lower instrument panel designed to minimize knee injuries in frontal crashes. But the tC doesn't have electronic stability control, which research shows can significantly reduce the risk of crashing -- especially getting into a serious single-vehicle crash, the IIHS said. This feature reduces fatal single-vehicle crash risk by 51 percent and fatal multiple-vehicle crash risk by 20 percent. 

Side impacts are the second most common type of fatal crash. More than 8,000 people were killed in side impacts in 2007. This compares with more than 14,000 deaths in frontal crashes. In the institute's side test, the C30 and Focus were rated "good." The Civic, Cobalt and tC were rated "acceptable" (The Cobalt's rating applies to vehicles built after May 2009, when General Motors modified this car's curtain airbags). 

In the Civic, forces on the driver dummy's chest and abdomen indicated that rib fractures and a fractured pelvis would be possible, IIHS said. The tC also was downgraded for torso protection. 

The Cobalt's "marginal" score for structural intrusion into the occupant compartment prevented this car from earning a "good" rating overall in the side test. 

Occupant protection in rear-enders has mostly lagged behind improvements in front and side crashworthiness, but the recently tested cars are exceptions, IIHS said. All but the tC earned "good" rear crash ratings. Neck sprain or strain is the most frequently reported crash injury in U.S. insurance claims. As automakers strive to earn Top Safety Pick, they're upgrading seats and head restraints. 

The Civic, Cobalt and Focus also are sold as four-doors, and the institute tested them previously. Frontal tests revealed only small differences between the two- and four-door versions, but differences in side test performance were more pronounced. For example, the four-door Civic earned a "good" rating in the institute's side test and is a Top Safety Pick, while the two-door version was rated "acceptable" in the side test because of higher forces on the driver dummy's chest, abdomen and pelvis, IIHS said.

On the other hand, the two-door Focus performed better than the four-door version, earning a "good" rating in the side test and a Top Safety Pick designation compared with the four-door's "acceptable" performance in the side test. 

"These differences confirm that crash test ratings for four-door cars can't automatically be applied to two-door versions," Zuby explained. "Still, the safety improvements we've seen for four-door vehicles generally appear to be carrying over to two-doors, which is good news for consumers."