Patient safety at Tobey Hospital could be good or it could be bad -- it really all depends on who you ask.

Tobey Hospital, one of three hospitals in the Southcoast Health System, recently received the HealthGrades Patient Safety Excellence reward, according to a Southcoast Health System press release.

The achievement ranks Tobey in the top 5 percent of all hospitals in the U.S. in patient safety by HealthGrades for the third year in a row, according to the release.

HealthGrades is a private, for-profit company that provides information about physicians and hospitals, according to MacLean Guthrie, a spokesperson for the organization. The company is independent from the organizations it reviews, said Guthrie.

At the same time, Tobey Hospital recently received a mediocre grade of "C" in patient safety from the Leapfrog Group, a not-for-profit organization that is run by employers and other large purchasers of health benefits.

Leapfrog's rating, also known as the Hospital Safety Score, is composed from data from Leapfrog's own hospital survey, as well as data from the Center for Medicare and Medicaid Services. In some cases, back-up data from the American Hospital Association is also used.

Tobey Hospital is disputing the report's finding that patient safety at the hospital is mediocre at best, and officials argue that Leapfrog's methodology is flawed.

"Southcoast does not participate in the Leapfrog survey due to concerns about the methodology used in conducting the survey, including the vagueness of the survey criteria, the lack of auditing and the lack of hospital participation nationwide," according to a Tobey Hospital statement.

Because Tobey Hospital did not participate in the Leapfrog survey, the grade of "C" was determined from data collected from Center for Medicare and Medicaid Services.

HealthGrades also used a similar source for determining its Patient Safety Excellence Award winners.

HealthGrades used data from the Medicare Provider Analysis and Review, which is a database that was purchased from the Center for Medicare and Medicaid Services, according to "Patient Safety Methodology 2012," a HealthGrades document explaining its methodology.

The two rating agencies also used similar criteria by which to measure patient safety at Tobey Hospital.

For example, according to Guthrie, HealthGrades looked at whether a patient developed bed sores, had breathing problems after surgery, or developed blood clots as criteria by which to measure patient safety.

The criteria were shared with Leapfrog's analysis, according to survey results for Tobey Hospital, available online at www.hospitalsafetyscore.org, and a scoring methodology pamphlet published by Leapfrog earlier this month.

Some criteria were different between the rating agencies, however.

For example, HealthGrades looked at whether there was electrolyte and fluid imbalance after surgery, while Leapfrog did not. Leapfrog looked at whether patients developed air embolisms, which HealthGrades did not look at, according to Guthrie.

Leah Binder, Chief Executive Officer of the Leapfrog Group, pointed to differences between the two surveys which could account for their different results.

"I'm sure HealthGrades has a scientific perspective, but they probably look at different things than we are," Binder said.

Binder said that Leapfrog did not punish hospitals for not participating in their surveys. She also said that, despite Tobey Hospital's disagreement with their methodology, patients should to be concerned about the hospitals that received a low grade.

"The data is the data. ... People in the community should remain concerned about their performance on safety," Binder said, adding that she hoped the hospitals with low scores "are doing all they can to reassure the public about their safety and [what] they're doing to improve their safety."

In a letter to employees, Keith Hovan, president and CEO of Southcoast Health System, said that the 3 Southcoast hospitals, including Tobey, are already keeping patients safe.

"Collectively we do a fabulous job with patient safety and quality and always score among the best in the nation. And we have the evidence to back it up," said Hovan, pointing to the HealthGrades award as well as other distinctions received by the Southcoast Health System.

"We are doing incredible things here at Southcoast," Hovan wrote, "and all of you should be proud of our exceptional record for patient safety and quality."