DETROIT - The Dodge Neon, Ford Focus and Volkswagen New Beetle are among the small cars that got the lowest safety rating in new side-impact crash tests performed by the insurance industry, according to results released Sunday.

Eleven of the 13 cars tested earned a "poor," the lowest of four ratings, the Insurance Institute for Highway Safety said. The Chevrolet Cobalt and the Toyota Corolla earned the second-highest rating of "acceptable," but only when they were tested with their optional side air bags. They earned "poor" ratings without the air bags.

Other vehicles that earned a "poor" rating were the Hyundai Elantra, Kia Spectra, Mazda 3, Mitsubishi Lancer, Nissan Sentra, Saturn Ion, Suzuki Forenza and Suzuki Aerio.

The institute's test simulates a severe crash. A barrier designed to resemble the front of a pickup or sport utility vehicle hits the side of the vehicle at 31 mph. A "poor" rating means a high chance of serious injury in a similar crash.

Four of the vehicles tested - the Elantra, New Beetle, Forenza and Spectra - have standard, head-protecting side air bags. But the institute's chief operating officer, Adrian Lund, said the cars had poor structure that failed to prevent injuries to the torso and pelvis.

Several of the vehicles offer optional side air bags, but the institute will only test those vehicles without side air bags unless the manufacturer provides a second vehicle with the option installed.

Toyota Motor Co. provided the Corolla with side air bags and General Motors Corp. provided the Cobalt and Saturn Ion. But even when it was tested with its optional side air bags, the Ion got a "poor" rating because the institute said it didn't adequately protect the driver's lower body.

GM said in a statement that the Cobalt and Ion meet or exceed all federal vehicle safety standards and got higher ratings in the institute's frontal crash tests.

The institute was most critical of the Neon, saying the car performed so poorly that the driver likely wouldn't have survived the crash. DaimlerChrysler AG defended the Neon, saying it meets federal safety standards and its performance is similar to other small cars.

"No single test can determine a vehicle's overall safety performance or how the vehicle will perform in a specific crash," DaimlerChrysler said in a statement.

Lund said the ratings were similar to frontal crash test ratings for small cars in 1997. Since then, manufacturers have redesigned those cars and now most get the highest safety rating in frontal crash tests.

"As manufacturers redesign their vehicles, we expect that small cars will get better in the side-impact test too," Lund said.