Fifteen years ago the family sedan and ever more popular sports utility vehicle were the David and Goliath of the highways, a mismatch that David rarely won when they collided.

David, it was revealed by a study released Wednesday, is doing better these days.

Safety features introduced to both cars and SUVs in the past decade have reduced the number of additional deaths caused by the inequity in size, according to a study by the Insurance Institute for Highway Safety.

In 1996, the National Highway Traffic Safety Administration said that 2,000 people killed in crashes would have survived if their vehicle had collided with a sedan rather than a heavier SUV or pickup truck.

At the time, auto manufacturers, who were making almost half their sales in the light truck category, which includes SUVs, said the unfortunate trend was mostly a matter of weight winning when vehicles collided.

NHTSA agreed that SUVS were “twice as likely to cause a fatality in the struck car than a passenger car of comparable weight,” but asked whether design changes could make a difference.

In 2003, the auto industry embraced changes that the Insurance Institute, which has access to the most comprehensive crash data in the nation, says have made a difference.

In fact, the institute found, occupants of sedans and minivans now are slightly more likely to die in a collision with another car or minivan than they are when they hit an SUV.

Ten years ago, people in cars or minivans died at a rate of 44 per million registered vehicles when they collided with SUVs and pickups. The number dropped by nearly two-thirds, to 16, by 2008-2009. When they collided with other cars and minivans that year the rate was 17 per million.

There are two main reasons that deaths have decreased in the lighter vehicles, the report said. Front air bags now are standard, and side air bags are common in vehicles of all weight classes.

And the front end of SUVs have been redesigned to lower their bumper level so that they are more compatible with those of cars and minivans. That has reduced the chance that an SUV will ride up over a smaller vehicle in a head-on or rear-end collision.

The advent of electronic stability control (ESC), now required on new cars by the federal government, also played a role.

“New designs and technology like side air bags are making it safer for cars, SUVs and pickups to share the road,” said institute chief Joe Nolen, who co-authored the study.

The institute, which is supported by the insurance industry, studied accidents involving late model SUVs and pickups in two time periods: 2000-01 and 2008-09. By 2008-09, SUVs posed no more risk than any other vehicle, although pickups still killed more people in cars and minivans, particularly in frontal crashes.

“Pickups lagged behind other vehicles in getting ESC, and designs of some top-selling models were slow to change,” Nolan said. “Those facts help explain why the numbers didn’t improve as much for pickups as for SUVs. Also, pickups often carry loads, so the trucks in these crashes could be a good deal heavier than their curb weights.”

The study results were well received by NHTSA Administrator David Strickland, who thanked automakers for the safety advances that have contributed to a steady decline in the number of people killed yearly in crashes.

The number dropped to 32,788 in 2010, the lowest total since 1949, according to data compiled by NHTSA, and a 25 percent decline since a peak of 43,510 in 2005.