High-priced convertibles may not actually guarantee more safety than their cheaper competitors, a new study has found.

The Insurance Institute for Highway Safety released a study Thursday that found expensive convertibles did not necessarily guarantee more safety. Tests were conducted on 10 new midsize convertibles; however, many of them did not receive good ratings.

"We had five cars overall that got good ratings in the front and side tests and some of the least expensive models earned the highest rating in the front and side tests," Russ Rader of the Institute for Highway Safety told CTV's Canada AM.

Among the five that received good ratings are the 2007 Mitsubishi Eclipse Spyder, 2007 Volkswagen Eos and 2008 Chrysler Sebring. These vehicles received the highest marks in front and side-impact crash testing and carry a price tag starting under US$30,000.

The two vehicles that scored highest on the test were also among the most expensive. The 2007 Saab 9-3 and 2007 Volvo C70 scored well in front, side-impact and rear crash protection tests and they start at around $40,000.

"They have electronic stability control as standard equipment, which can help you avoid crashes altogether and we're adding a new requirement for the top safety pick designees in the convertible category and that is that they have some sort of rollover protection," Rader said.

"Both the 93 and the C-70 which are our top safety picks have roll bars that store behind the rear head restraints and only deploy when the car senses a crash."

Pop-up roll bars were standard equipment on five of the cars tested, but were unavailable on the others.

At the other end of the spectrum, some cars fared poorly. The Pontiac G6, The BMW Series 3 and the Audi A4 were the lowest rated cars in the survey.

Rader said the Pontiac G6 was acceptable in the frontal test but that all three were disappointing when their side-impact effectiveness was assessed.

"What's especially disappointing in the case of the Pontiac and the BMW is these are brand new cars," Rader said. "They just came out and you would expect that they would offer state-of-the-art protection."

Other vehicles that returned notable results in the study were the 2007 Toyota Camry Solara and the Ford Mustang. The Camry Solara received the highest rating in the frontal test and the second-highest mark in side-impact evaluation.

The Ford Mustang placed second in frontal impact testing and the highest marks in side-impact.

This was the first time the Insurance Institute for Highway Safety assessed convertibles for crash testing.

With files from the Associated Press