All in the Numbers: Making Sense of Hospital Compare Readmission Data

The Centers for Medicare and Medicaid Services (CMS) released this month first-time data in its Hospital Compare Web site that reports if patients returned to an individual hospital within 30 days after being discharged for three conditions: heart attacks, heart failure, or pneumonia.

Hospital Compare data show that on average for patients admitted to a hospital for heart attack treatment, 19.9% of them will return to the hospital within 30 days, 24.5% of patients admitted for heart failure will return to the hospital within 30 days, and 18.2% of patients admitted for pneumonia will return to the hospital within 30 days.

More than 4,000 hospitals—including almost all acute care hospitals—have voluntarily submitted quality information to share with the public through the Web site. Hospitals were placed in one of three categories based on their readmission rate—compared with the national readmission rate: "no different than the U.S. national rate," "better than the U.S. national rate," or "worse than the U.S. national rate."

So what does this data mean? Is a hospital in trouble if it is ranked "worse" than the national rate? Well, not quite. Even in its own explanation, CMS urges consumers not to view any one process or outcome measure on Hospital Compare as a tool to "shop" for a hospital.

But it's important for hospitals to understand how this current year's data is obtained. First, the data used in the Web site looks at data averaged over a three-year period of time.

"So where improvements have been made in the last year—that's not necessarily going to show up in data right now," said Jayne Hart Chambers, Senior Vice President for Strategic Policy and Corporate Secretary with the Federation of American Hospitals (FAH). FAH is a member of the Hospital Quality Alliance, which has collaborated with CMS on the development of its public quality reporting efforts.

"The other thing to understand about this particular measure is that readmission to a hospital within 30 days . . . is not necessarily related to the underlying condition that [the patient was] originally discharged," Chambers said.

For instance, if a patient was discharged after being admitted for heart failure and then returned to a hospital within 30 days because of a broken leg, that would be considered a readmission. "I've seen a couple of stories that have said a fifth of heart failure patients come back to a hospital—implying that they've come for their heart failure. That's not an accurate interpretation of this data," Chambers said.

Ongoing research, though, has indicated that patients may return to a hospital within several days when problems may arise with their discharge—perhaps they didn't understand their discharge directions or questions arose over prescriptions. A number of hospital-based programs around the country have found that using their own data and improving communications during discharge can make a difference in lowering readmissions.

"It's the care coordination aspect of it," Chambers said. "In my view, this is sort of the gross measure of an area that needs to be addressed. There's clearly a lot of public interest in it, and the tools that we have to address it right now are sort of sledgehammer kind of tools."

As recent legislation on Capitol Hill has shown, the issue of readmission within 30 days is not going to go away. It's become a well-known target within current healthcare reform legislation.

But it is going to take some time and work for all hospitals to address. While the data may not be truly reflective of why readmissions are taking place, they may serve as a wake-up for hospitals—and their leaders—to ask what is happening within its walls, and if there indeed is more room for improvement.