The trauma center where Louisiana Rep. Steve Scalise has been treated since his gunshot wounds last month is ranked low even when compared to other level 1 trauma centers, including some in other diverse urban areas like Washington, D.C.

Patients who are taken to a level 1 trauma center have about a 25% better chance of survival over other hospitals, according to a 2006 study in the New England Journal of Medicine (NEJM). These hospitals, including Scalise’s Medstar Washington Hospital Center, treat the most seriously injured patients.

But 34 adult level 1 trauma centers across the U.S. get A grades for safety from the Leapfrog Group and they include hospitals in Boston, Philadelphia, Cleveland and Providence, R.I. Washington Hospital Center gets a D.

Leapfrog doesn't separate out trauma centers in its ratings, but did an analysis of level 1 trauma center grades for USA TODAY.

"It stands to reason that of all the patients in the hospital, trauma patients would be the most vulnerable to shortfalls in hospital safety and thus trauma centers should be located in the safest possible hospitals," says Leapfrog CEO Leah Binder.

Trauma surgeons have mixed views on whether these grades matter, but hospitals that do well regularly put out press releases and sometimes include the scores in advertising for a small fee.

Trauma surgeon Ronny Stewart, who chairs the American College of Surgeons' trauma committee, is among the skeptics about the value. He says ACS verifies when trauma centers meet "rigorous national standards" for "continuous quality improvement."

"Once people are getting a public grade. some hospitals do pay more attention to it than others," says Stewart, "But the way we (ACS) approach it, leads to proven improvements in outcome."

Binder says consumers should definitely care about ratings.

Leapfrog's safety grade "focuses only on the bad things patients want to avoid, like medical errors and infections," says Binder. "These problems are all too common, with more than 500 people a day dying from preventable errors in hospitals."

Washington Hospital Center is among just 12% of level 1 trauma centers in the country that get a D rating. Nearly 17% scored an A, about 29% a B and about 42% a C.

Washington Hospital Center also scores two out of five stars in the Centers for Medicare and Medicaid Services' Hospital Compare ratings. Massachusetts General Hospital, which also includes a level 1 trauma center, gets four out of five stars from CMS and an A from Leapfrog.

Even among level 1 trauma centers, "not all of us do the same type of trauma," says Jason Smith, a trauma surgeon who is the new chief medical officer at University of Louisville Hospital. Hospitals "see a very different volume and type of patients."

The location and type of injury can also greatly increase the risk of infection. Scalise was shot in the pelvis, which increases risk of contact with the colon and the chance of stool getting in the bloodstream.

Other challenges: Hospital data doesn't distinguish well between types of patients. For example, an elderly person who falls and breaks a hip is identified with the same diagnostic code as a person who is shot and breaks a hip, says Smith.

Leapfrog mostly uses Medicare data which "applies highly sophisticated risk-adjustment formulas to its measures," says Binder. Leapfrog's ratings also include questionnaires that some hospitals, including Washington Hospital Center, refuse to answer but Binder notes many hospitals get As anyway. The overall ratings are "exhaustively vetted" by a range of stakeholders and experts, she says.

Washington Hospital Center spokeswoman Donna Arbogast says "we do voluntarily participate in those programs that effectively assess quality and safety."

Along with complication rates, Leapfrog scores hospitals on incidents including "accidental cuts and tears" and "dangerous object left in patient's body" after surgery. For issues like that, it shouldn't vary based on whether someone was poor, Binder says.

Like Scalise's hospital, Smith's also gets a D, but was above average on the dangerous objects and below average on the cuts and tears. Washington Hospital Center scored below average on both.

"I would love to fix and change everything at once, but you have to identify the areas you want to approve in where there is the biggest bang for the buck," Smith says. "You can’t change 40 things all at once."

Thomas Scalea, physician in chief at University of Maryland in Baltimore's R Adams Cowley Shock Trauma Center, also downplays the significance of quality ratings. Maryland has a federal waiver to run its Medicare program differently so hospitals don't report the same data and aren't rated by CMS or Leapfrog.

"There are many ways to game that system so you look better than you actually are," says Scalea, who is also a professor at University of Maryland's medical school. "I don’t really think many of those measurements actually measure quality — at least not always."

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For example, Scalea notes, "if everyone dies early, you don't have infections." Similarly, he says, if hospitals don't draw blood cultures, they'll never find infections but that wouldn't be a "good way to take care of patients."

Smith says he believes hospitals all try. There are just dozens of metrics and "it takes a lot of work" to keep up with them all.

And, although their Leapfrog scores have gone down rather than up, Washington Hospital Center spokeswoman So Young Pak says there's a lag time in the data and defends their record.

"We are a recognized leader in embracing transparency, and we continuously use our outcomes data to learn, improve and optimize the care we provide to 40,000 inpatients every year," she said in a statement.