How good a hospital is St. Mary Mercy Livonia Hospital? Depends on whom you ask. The Leapfrog Group, a respected nonprofit that promotes patient safety, gave an "A" to this Michigan hospital. The company Healthgrades named it one of America's best 50 hospitals. But the Joint Commission, a nonprofit organization that accredits hospitals, and U.S. News and World Report omitted St. Mary from their best hospital lists. Consumer Reports gave it an average safety score of 47 points out of 100, citing high numbers of readmissions, poor communication with patients and excessive use of scans. Medicare, which has a new program rewarding hospitals for meeting certain quality measures, is reducing St. Mary's payments by a fraction this year.