How hospital ratings work
CMS publishes dozens of quality measures for every Medicare-certified hospital. This section explains what each one actually measures, which direction is good, and where the numbers mislead. We publish no ratings of our own.
The Overall Star Rating
How CMS turns dozens of measures into one 1-to-5 star score, and why hundreds of hospitals have no star at all.
Safety & Infections
What a standardized infection ratio of 0.8 means, and why complication rates need a denominator to make sense.
Patient Experience (HCAHPS)
Who gets surveyed, what they are asked, and why "always" is the only answer CMS counts.
Readmissions & Mortality
Why a 30-day window, what "risk adjusted" changes, and when a high rate is not the hospital's fault.
The five categories behind the star
CMS groups its measures into these categories and weights them to produce the overall star rating.
| Category | What it measures | Better is |
|---|---|---|
| Mortality | How often patients died within 30 days of being treated for certain conditions. Lower is better. | Lower |
| Safety of Care | Infections and surgical complications that happened during a hospital stay. Lower is better. | Lower |
| Readmission | How often patients had to come back to a hospital within 30 days after being discharged. Lower is better. | Lower |
| Patient Experience | Results from surveys of patients after they went home. Higher is better. | Higher |
| Timely & Effective Care | How quickly patients were treated and whether the hospital followed recommended steps of care. | Depends on the measure |
Weighting varies by what each hospital reports. CMS documents the full methodology in its Overall Star Rating methodology report.
Articles on hospital ratings
Deeper explanations of individual measures and what they mean for a decision.
Healthcare-Associated Infections: How to Check Your Hospital
Healthcare-associated infections (HAIs) are infections patients acquire during the course of receiving treatment in a healthcare
Hospital Readmission Rates: Why They Matter for Your Care
Hospital readmission rates measure how often patients return to the hospital within 30 days of being discharged. High readmission
Hospital Mortality Rates: What the Numbers Really Mean
Hospital mortality rates measure how often patients die during or shortly after a hospital stay. These statistics are among the
CMS Hospital Star Ratings Explained: A Complete Guide
The Centers for Medicare & Medicaid Services (CMS) assigns overall star ratings to hospitals across the United States. These
US News Hospital Rankings vs CMS Stars: What's the Difference?
Two of the most prominent hospital rating systems in the United States are the U.S. News & World Report Best Hospitals
Hospital Safety Grades: What Do A, B, C, D, F Mean?
Hospital safety grades provide patients with an easy-to-understand assessment of how well hospitals protect patients from
HCAHPS Scores Explained: What Patient Surveys Really Measure
HCAHPS (Hospital Consumer Assessment of Healthcare Providers and Systems) is the first national, standardized survey measuring
What Is a Good Hospital Rating? Understanding 1 to 5 Stars
When researching hospitals, you'll encounter star ratings that range from 1 to 5. But what constitutes a "good" rating, and how
Common questions
Does a 5-star hospital always give better care than a 3-star hospital?
No. The star rating averages measures across many conditions, so a hospital can be excellent at cardiac surgery and average overall, or the reverse. If you know what care you need, the individual measure matters more than the summary star.
Why do so many hospitals have no star rating?
CMS only calculates a star rating when a hospital reports enough measures with enough cases to be statistically reliable. Critical access, psychiatric, children's and federal hospitals are excluded by design. A missing star says nothing about quality of care.
How current is this data?
CMS refreshes hospital data roughly quarterly, and each measure covers a reporting period that ended months earlier — mortality measures often span three years. So the numbers describe how a hospital performed in the past, not how it is performing today.
Does HospiGuide rank hospitals or publish its own ratings?
No. Every number on this site comes from CMS. We add plain-English labels, explain which direction is better, and compare each hospital with the national median — but we never calculate a score of our own, accept payment for placement, or publish user reviews.
What does "compared to the national benchmark" mean?
For mortality, readmission and infection measures, CMS compares a hospital with the national result using a confidence interval. "No different than the national benchmark" means the difference is small enough that it could be chance — which is the most common result, and a perfectly normal one.