ARLINGTON, Va. --- A new study from the Insurance Institute for Highway Safety (IIHS) concludes that greater vehicle roof strength substantially reduces the risk of fatal or incapacitating driver injury in single-vehicle rollover crashes. It's a conclusion that contradicts the findings from two previous studies on the topic.

Though the study focused on midsize SUVs, "there is no obvious reason similar relationships would not be found for other vehicle types, although the magnitudes of injury rate reductions may differ," the study noted.

Titled "Roof Strength and Injury Risk in Rollover Crashes," the study tested 11 midsize SUVs. Those with the strongest roofs posed injury risks 39 to 57 percent lower compared to those with the weakest roofs, IIHS said. Collisions involving rollovers account for about 35 percent of all occupant deaths.

The National Highway Traffic Safety Administration is now working to update the federal standard for vehicle roof strength.

To read the IIHS study, click here.