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For Immediate Release
Thursday, July 09, 2009



The Centers for Medicare & Medicaid Services (CMS) has expanded the amount of information available on its Hospital Compare Web site at

As of July 2009, the Web site will now include updated information on 30-day mortality rates for patients admitted to many inpatient hospitals for heart failure, acute myocardial infarction (heart attack), and pneumonia. The Web site also includes the debut of new 30-day readmissions measures for patients who were originally admitted to these hospitals for one of these 3 conditions.

This information is shared with consumers and providers to improve the quality and transparency of care by giving the American public and healthcare professionals better access to important hospital data. The new readmissions measures complement the mortality measures and the clinical process and patient satisfaction measures already reported on Hospital Compare to promote increased scrutiny by hospitals of patient outcomes in the service of providing the right care for every patient, every time.

Background: Data about Hospital Care

CMS has been reporting information about the quality of care available at America’s hospitals for several years. Before 2007, this information was limited to "process of care measures," the rates of which demonstrate how well hospitals follow generally recognized protocols believed to result in the best patient outcomes. However, these "process of care measures" failed to capture how well patients fared as a result of these care protocols.

In 2007, CMS began reporting 30-day mortality rates for inpatient hospital stays related to heart attack and heart failure. CMS added 30-day mortality rates for pneumonia-related stays in 2008. Mortality rate measures are "outcome" measures because they give an indication of how the patient fared after the inpatient hospital stay. The rates themselves are actually predictions of

how many patients will die within 30 days of discharge from the hospital (after having been admitted for heart attack, heart failure, and pneumonia), and are "risk adjusted" to account for extraneous influences, such as the difference among hospitals in the degree of their patients’ illnesses. CMS placed each hospital into one of three categories, based on their mortality rates: "Better than U.S. National Rate," "No Different than U.S. National Rate," or "Worse than U.S. National Rate."

Updates to Hospital Compare: Adding Readmissions Data

Similar to the mortality measures, the readmissions measures are also outcome measures. In July 2009, CMS debuted a new set of measures on Hospital Compare that show 30-day all-cause readmissions for patients who had been admitted to the hospital for heart attack, heart failure, and pneumonia. About 1 in 5 patients who leave the hospital will be readmitted within 30 days of discharge. Researchers have noted that readmissions are too common and costly, and that they are often preventable.

These measures complement the mortality data already available on the Hospital Compare Web site to provide a complete picture of the outcomes of care in many of America’s hospitals. Measuring and reporting readmissions information places a spotlight on the entire spectrum of care that hospitals provide, as well as the care that patients receive from other providers after being released from the hospital. Some readmissions are inevitable; however, learning more about how well patients are doing after they leave the hospital is paramount to CMS’s goals to combat poor quality and to positively impact the lives of Medicare beneficiaries and the health of the American public overall.

Methods for Calculating Outcomes Measures

The CMS readmissions and mortality measures are risk-adjusted measures and were developed by a team of clinical and statistical experts from Yale and Harvard Universities under the direction of CMS. The National Quality Forum (NQF) endorsed the measures following a rigorous review process involving providers, consumers, purchasers, and researchers.

The model CMS uses to assess hospital readmissions and mortality rates is based on claims data and has been validated by models based on clinical data. It takes into account medical care received during the year prior to each patient’s hospital admission, as well as the number of admissions at each hospital. The model uses this information to adjust for differences in each hospital’s patient mix, so that hospitals that care for older, sicker patients are on a "level playing field" with those whose patients would be expected to be at less risk of dying within 30 days of admission.

In 2007 and 2008, CMS reported this mortality data based on one year of hospital claims. Starting in June 2009, CMS expanded its calculations to include three years of hospital claims for its mortality measures. The measures on Hospital Compare now include data on discharges that occurred from July 1, 2005, through June 30, 2008. These additional two years of data provide a clearer picture of hospital outcomes, and will help consumers make better distinctions among the performance levels of hospitals in their communities. Readmissions measures also reflect 3 years of data.

Certain Exclusions from Measures

Certain admissions are excluded from the calculation of the mortality and readmissions measures. For example, CMS excludes claims from its mortality calculation when a patient was enrolled in the Medicare hospice program on the first day of admission or the 12 months prior to hospital admission because the agency recognizes that this could potentially skew the hospital’s mortality. Likewise, CMS excludes from its calculation of the heart attack readmission measure patients who have been readmitted to the hospital within 30 days of a discharge after heart attack when the readmission is for the purpose of a planned cardiac treatment, such as a heart bypass or a coronary angioplasty. Lastly, CMS excludes from the mortality and readmissions measure calculations admissions of patients who left the hospital against medical advice, because those hospitals may not have been able to provide the best care possible for these patients.

In addition, CMS does not report mortality or readmissions data for hospitals that have treated fewer than 25 cases during the relevant reporting period in any of the mortality or readmission measure categories. Without at least 25 cases, CMS cannot make an accurate estimate of the hospital’s performance for a particular measure. For those hospitals with fewer cases, the Hospital Compare Web site reads, "the number of cases is too small to reliably tell how the hospital is performing."

CMS updates most of its Hospital Compare measures quarterly. To learn more about the quality of care available at your local hospital, visit Hospital Compare at

Outcome Measure Results for July 2009 Reporting


(July 2005-June 2008 Discharges) Measure U.S. National Rate Performance Category … Number of Cases Too Small*
Better than U.S. National Rate No Different than U.S. National Rate Worse than U.S. National Rate
AMI 30-Day Mortality 16.6% 131 2,814 54 1,610
HF 30-Day Mortality 11.1% 213 3,812 163 585
PN 30-Day Mortality 11.5% 253 3,934 284 343
AMI 30-Day Readmission 19.9% 36 2,488 52 1,944
HF 30-Day Readmission 24.5% 180 3,854 233 520
PN 30-Day Readmission 18.2% 88 4,199 198 349