HARRISBURG — Pennsylvania's hospitals have experienced an overall decline in death rates for 25 conditions and procedures over a four-year period, a health care watchdog group said in a report released today.

The statewide patient mortality rate dropped to 4.2 percent in 2007 from 4.6 percent in 2004, the Pennsylvania Health Care Cost Containment Council said in its annual hospital performance report.

The largest mortality rate decline in a single treatment category was in respiratory failure without mechanical ventilation, from 17 percent in 2004 to 11.7 percent in 2007, the report said.

The council's study also found a slight increase in readmission rates for 19 conditions and procedures over a three-year period, from 18.6 percent in 2005 to 18.7 percent in 2007.

Carolyn F. Scanlan, president and chief executive officer of the Hospital & Healthsystem Association of Pennsylvania, said the report was generally good news for hospitals, but cautioned that chronic illness may be responsible for some readmissions.

"The linkage between the significant decline in mortality rates and the slight increase in readmission rates reflects the fact that the quality of care hospitals provide is saving more lives than ever," Scanlan said. "However, many of those surviving patients are the most chronically ill — and therefore most in need of continuing hospital care."