Make cardio stats work for, not against you

PA mandates CABG outcomes disclosure

What prospect is more frightening than being forced to release data on the performance of your hospital’s cardiologists to the public? What about newspapers publishing your outcomes and reporters asking you to justify those numbers?

Much to their surprise, Pennsylvania hospitals are finding that airing cardiology outcomes information isn’t such a bad thing. In fact, in the four-year period beginning in 1991 during which the annual Consumer Guide to Coronary Artery Bypass Surgery was published, the mortality rate for coronary artery bypass grafting (CABG) across Pennsylvania hospitals dropped 26%. The average increase in hospital charges for the procedure dropped as well from 10% to 4.6% in the same period, says Joe Martin, spokesman for the state agency created to implement the law, Pennsylvania Health Care Cost Containment Council in Harrisburg.

Since Pennsylvania mandated disclosure 10 years ago, many hospitals have been able to make the statistics work for them instead of against them, in terms of improving care for patients and increasing market share. The original intent behind the law — to restrain costs and improve quality of care by stimulating a competitive health care market — is working.

The only other states with a public effort somewhat similar to Pennsylvania’s are New York and Michigan, where mortality rates of patients undergoing CABG surgery are made public. (See story on Michigan’s initiative, p. 138.) Twenty-eight states recently approved health care data arrangements as part of a national trend toward public disclosure. "The trend is based on free market economics," Martin says. "As patients and group purchasers are able to identify hospitals and doctors with the best prices and quality, providers are forced to compete by restraining their costs and improving the quality of the care they provide."

Hospitals in Pennsylvania provide a variety of data, including severity-adjusted mortality and morbidity rates, patient volumes, average lengths of stay, and average hospital charges on about 60 diagnostic related groups (DRG) each year. The council published the data in more than 80 public reports and in more than 300 customized reports by request. The reports, which receive a good deal of media attention, are made available on request and distributed to such places as public libraries. Patients also may call the council looking for information on a particular hospital or surgeon.

"There was a fair amount of anxiety and grumbling early on in the process, but hospitals have begun to see the system’s value," Martin says. The process supplies hospitals with information on other facilities, giving them a context for their own data. Now they can compare their facilities with competitors and use the results in strategic planning, marketing, and recruiting physicians.

A study led by Harry Evans, PhD, professor of business administration at the University of Pittsburgh showed that the mandated public disclosure had a significant effect on Pennsylvania hospitals, such as:

- Hospitals with poor mortality outcomes in the first year of disclosure showed significant improvements in quality later.

- Hospitals in markets with more intense competition were more likely to show improvements in mortality outcomes.

- Poorly performing hospitals lost market share in the period following disclosure, while better performing hospitals gained market share.1

The biggest improvements were seen in DRGs that were the most important financially for the hospital.

High-risk patients could skew stats

"You might get a bad outcome even if you’re doing a good job," he says. "But this may be the step that helps hospitals think about what they’re doing and implement programs to move them further along. It’s well worth gathering the data just so you can compare yourself to other hospitals. It passes my cost-benefit test."

A possible negative implication of this type of data collection is that hospitals could be reluctant to take on high-risk patients who might skew their statistics, Evans says. But at least one study has shown that doesn’t happen. The federal Agency for Health Care Policy and Research in Rockville, MD, funded a study of New York State’s disclosure of CABG mortality rates.2 It showed that hospitals and surgeons with the lowest risk-adjusted mortality rates for all cases also had the lowest mortality rates for high-risk cases.

"With a movement toward further dissemination of patient outcomes to health insurance companies, other payers, and the public, providers may become progressively more wary of high-risk cases," writes lead author Edward L. Hannan, PhD, of the Working Group Panel on the Cooperative CABG Database Project in Rensselaer in New York.


1. Evans H, Hwang Y, Nagarajan N, et al. Involuntary Benchmarking: The Effect of Mandated Public Disclosure on Hospitals. Presented at the Sixth Annual Conference of Financial Economics and Accounting. The University of Maryland College of Business and Management, College Park, MD; November 1995.

2. Hannan E, Siu AL, Kumar D, et al. Assessment of coronary artery bypass graft surgery performance in New York. Medical Care 1997; 35:49-56.