Mortality Rate (Hospital)
The rate of patient deaths within 30 days of hospital admission for specific conditions, risk-adjusted to account for differences in patient severity.
Mortality Rate (Hospital) is a term from U.S. hospital cost and quality reporting — the field that produces the CMS Hospital Compare program, the Medicare Inpatient Payment files, and the patient-facing tools built on top of them. The definition below covers what the term means in CMS files, what it does not mean, and how it interacts with the other measures CMS publishes. On the LakeQuality value rubric, Mortality Rate (Hospital) is one of the inputs (directly or indirectly) to the combined cost-and-quality grade. Understanding how the term is computed at CMS — what counts and what does not — is part of reading hospital pages defensibly.
Each hospital page on LakeQuality surfaces the specific Mortality Rate (Hospital) value for that facility (when CMS reports one), so the general definition here translates into a concrete data point on the per-hospital pages you actually use.
How It Works
CMS tracks risk-adjusted 30-day mortality rates for seven conditions: acute myocardial infarction (AMI/heart attack), heart failure (HF), pneumonia, chronic obstructive pulmonary disease (COPD), stroke (ischemic), coronary artery bypass graft (CABG), and abdominal aortic aneurysm repair for select measures. Each hospital's observed mortality is compared to an expected mortality calculated from a hierarchical logistic regression model that adjusts for patient age, sex, and 30-60 clinical comorbidities drawn from the 12 months of Medicare claims preceding the admission. The comparison is expressed as an estimated readmission/mortality ratio, and hospitals are categorized as "better than national rate," "no different than national rate," or "worse than national rate." Nationally, 30-day mortality runs approximately 12-15% for AMI, 10-12% for heart failure, 15-17% for pneumonia, 8-10% for COPD, 14-17% for stroke, and 3-4% for CABG. A hospital flagged as worse than national rate on multiple conditions is a serious safety concern that typically drives board-level attention, consulting engagements, and leadership turnover. Mortality measures are heavily scrutinized for risk adjustment adequacy, since hospitals treating the sickest patients (large academic medical centers, safety-net hospitals) argue that even sophisticated risk models underestimate case acuity. Studies in Health Affairs and JAMA have documented that teaching hospitals often show statistically similar risk-adjusted mortality to community hospitals despite treating more complex cases, suggesting the models adequately adjust for severity. Mortality results are publicly reported on Medicare.gov Care Compare and feed the CMS Overall Hospital Quality Star Rating with 22% weight. Hospitals with persistent worse-than-expected mortality often pursue Mortality Reduction Collaboratives and may adopt specific bundles like the Surviving Sepsis Campaign for sepsis mortality or door-to-balloon time reduction for AMI.
Related Terms
- CMS Star Rating (Hospital Overall Rating), A 1-to-5 star rating assigned by CMS to each hospital based on 46+ quality measures, covering mortality, safety, readmissions, patient experience, and timely care.
- Readmission Rate, The percentage of patients who return to the hospital within 30 days of discharge for the same or related condition, a key quality metric tracked by CMS.
- Value Score, HospitalCostData's proprietary A-F grade combining price (40%), quality rating (40%), and patient outcomes (20%), measuring whether a hospital delivers good care at a fair price.
- Hospital-Acquired Condition (HAC) Reduction Program, A CMS program that reduces Medicare payments by 1% for the quartile of hospitals with the highest rates of hospital-acquired conditions, including infections and preventable injuries.
- Leapfrog Hospital Safety Grade, A letter grade (A-F) assigned twice yearly to U.S. hospitals by The Leapfrog Group, a nonprofit founded by large employers, based on 30+ patient safety measures.
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About This Definition
This definition is part of the HospitalCostData Hospital Pricing Glossary, 47 terms explaining hospital costs, quality ratings, and healthcare billing. Written for patients, journalists, researchers, and healthcare professionals.