Now we can disclose that the Audi A4 convertible is in the same position.

In a statement, the Institute indicated that "the absence of a roof makes it a challenge to design a convertible for safety. The roof helps to maintain the rigidity of the structure around the occupant compartment and keep the compartment intact in a serious crash. The main structures of convertibles have to be strengthened to compensate for the support that's lost in removing the roof. The Institute's crash test results show that many modern convertibles compensate well. For example, the (Saab) 9-3 convertible achieves the same good front, side, and rear crash test ratings as the 4-door sedan version."

The Audi A4 convertible gained a good rating in the frontal offset tests but rated marginal for side impact protection. However, the A4 convertible rated poor for protection in rear crashes, just like the new BMW 3-Series convertible.

"We wanted to test convertibles because sales are increasing," Institute president Adrian Lund said.

".... You could spend twice as much for an Audi A4 convertible, which is an older design based on the previous A4 sedan, but it's rated marginal in our side test," Lund says.