The National Highway Traffic Safety Admin. releases highly anticipated upgrades to its 5-star ratings system, but the agency's loudest critics say it missed an opportunity to take the program to a new level of sophistication.

“We've taken a step forward,” says Jack Gilles, director-public affairs for the Washington-based Consumer Federation of America, a consumer protection group, and author of “The Car Book,” the group's annual buyer's guide.

“But the bottom line is there was an incredible opportunity here for NHTSA to clean up one of the most important safety programs in America, and they did not go far enough,” Gilles says.

Anne Fleming, a spokeswoman for the Insurance Institute for Highway Safety, an auto insurers' group that also conducts crash tests and provides consumer ratings, agrees. “These are not huge changes,” she says. “They are still nibbling around the edges.”

Key changes to the ratings system include a single score that combines results from frontal, side and rollover tests and the addition of a small female crash-test dummy to the procedure so women and large children are better represented. NHTSA also adds a pole test to its side-impact exercise, which will simulate wrapping a car around a tree.

The changes take effect in testing '10 model-year vehicles. The administration admits its previous system had become obsolete as auto makers improved crashworthiness in recent years.

In 2007, about 97% of vehicles tested achieved the highest 5-star ratings. NHTSA called the system a “victim of its own success,” while critics more pointedly suggested it “neutered” safety competition among manufacturers.

“We want to make sure consumers can take safety into consideration when choosing a new vehicle, along with price, fuel efficiency, size and the color they like best,” says U.S. Transportation Dept. Secretary Mary E. Peters.

Gilles says the single score, rather than a star rating for both frontal- and side-impact crashworthiness, will help clear up consumer confusion and place pressure on OEMs to improve overall safety.

Often, he says, if an auto maker's vehicle scored poorly in the frontal-impact test but did better on side impacts, the OEM only would advertise the best number.

The new system will solve a gradation dilemma he says has plagued the program. But although it might tell consumers which vehicle scores a 5-star rating, the system still lacks detailed information on how each vehicle performed in context to direct competitors.

“It doesn't appear to me that NHTSA has addressed that,” Gilles says.

For frontal crash tests, NHTSA says it will retain the 35-mph (56-km/h) full-frontal barrier protocol, but also will update its test dummies and associated injury criteria to assign a frontal score.

Fleming says the IIHS, whose frontal offset-crash exercise complements NHTSA's front flat-barrier test, would have liked to see more progress on the frontal-impact procedure, perhaps through the inclusion of a narrow object test.

For side impact, NHTSA plans to retain the current moving deformable barrier test at 38.5 mph (63 km/h). But, as with frontal collisions, NHTSA will update the test to include new side-impact test dummies and new injury criteria.

For its rollover test, NHTSA will continue to rate vehicles for their propensity to roll over but will wait to update its risk model as additional real-world crash data becomes available for a growing number of vehicles equipped with electronic stability control.

New Rule Seeks to Improve Protection in Side-Impact Crashes