DETROIT (Reuters) - The Insurance Institute of Highway Safety said on Tuesday that four of 12 small SUVs it tested received its top rating for their ability to withstand roof damage in rollover accidents that often prove deadly.

It was the first time that the safety watchdog group, which is funded by the insurance industry, has released vehicle ratings based on a new roof strength rating system.

Four small SUVs received the top rating of "good" from the institute -- the Volkswagen Tiguan, Subaru Forester, Honda Element and Jeep Patriot.

Two small SUVs received "poor" ratings: the Kia Sportage and Hyundai Tucson.

The Sportage had the weakest roof tested among the dozen, the institute said. The Tiguan was the strongest, it said.

More than 10,000 people a year are killed in rollover accidents in the United States, according to the institute.

The problem has been worse in high-riding SUVs. About a quarter of occupant deaths in accidents with cars and minivans involve rollovers, but that percentage rises to 59 percent for SUVs, the institute said.

By other estimates, rollovers represent just 3 percent of vehicle crashes, but about a third of vehicle deaths.

The National Highway Traffic Safety Administration proposed in 2005 that current safety standards be raised to require that the roofs on all passenger vehicles be able to withstand a force of 2.5 times the vehicle weight without buckling enough to strike average-sized, buckled-in occupants.

But implementation of that standard stalled under the Bush administration.

Major automakers support the proposed NHTSA standards provided it is phased in but have opposed more stringent proposals backed by the insurance industry.

The current safety standard, written in 1973, sets a strength-to-weight ratio of 1.5 times and exempts heavier SUVs and pickup trucks.

To win a "good" rating, the insurance institute requires a vehicle to have a roof that can withstand a force of four times its weight before the roof crushes in by five inches.

The institute rated the Suzuki Grand Vitara, Chevrolet Equinox, Pontiac Torrent, Toyota RAV4, Nissan Rogue , Mitsubishi Outlander as "acceptable" for roof strength.

It gave "marginal ratings" to the Honda CR-V 7267.T and the Ford Escape, Mercury Mariner and Mazda Tribute.

The institute said it plans to assess roof strength on minicars and midsize cars as its next projects.

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