Medicare runs a program called the Five-Star Quality Rating System, published on its official Care Compare tool. It covers roughly 15,000 nursing homes across the country that are certified to take Medicare or Medicaid residents. The goal is to give families a quick way to compare homes. The catch is that the headline number hides three very different kinds of data underneath, and those kinds are not equally reliable. This guide walks through each one so you can read the stars the way CMS intends.
Care Compare shows four star scores for every home. Here is what each one measures and where its data comes from.
| Rating | What it measures | Where the data comes from | How objective |
|---|---|---|---|
| Overall | A combined summary score | Built from the other three | Only as good as its parts |
| Health inspection | Findings from safety and care inspections | Unannounced on-site state surveys, roughly yearly, plus complaint investigations | Most objective |
| Staffing | Nurse hours per resident per day | Payroll-based journal data submitted to CMS | Solid, verified against payroll |
| Quality measures | Clinical outcomes like falls, pressure sores, mobility | Resident assessments and Medicare claims | Useful, but partly self-reported |
CMS builds the overall rating in a set order. It begins with the health-inspection rating as the foundation, because that comes from trained surveyors who show up unannounced. Then it adjusts: a home with strong staffing can gain a star, and a home with weak staffing can lose one. Finally the quality-measures rating can nudge the total up by a star. The health-inspection score always carries the most weight, so a home cannot buy its way to five stars on self-reported numbers alone.
This is why the relationship between staffing and the star rating matters so much: staffing is the lever that moves the overall score up or down, and it is also the single best predictor of the care your parent will actually receive day to day.
Within each state, homes are ranked and sorted into groups for the health-inspection rating. Roughly the top tenth get five stars and the bottom fifth get one star, with the rest in between. Staffing and quality measures use national thresholds rather than a curve. Two practical consequences follow from this design:
The takeaway: read the four ratings separately, not just the headline star. Weight the health-inspection rating most, treat staffing as the day-to-day predictor, and read quality measures as helpful but partly self-reported. The stars point you toward the right questions. They do not answer them.
CMS refreshes the ratings on a rolling basis. Health-inspection results update as new surveys come in, staffing updates quarterly from payroll data, and quality measures update quarterly as well. That means a rating can lag a real change at a home by a few months, in either direction. A home under new management may still show old scores, and a home that has recently slipped may not have caught up yet. It is one more reason the ratings are a starting point and your own in-person visit is the finish line.
All of these figures come straight from Medicare's own Care Compare database, which is public and updated by CMS. Our report simply pulls the homes near your ZIP and lays their four ratings side by side, with the staffing hours and any flags in plain view, so you are not clicking through one profile at a time. You can see exactly how we handle the data on our methodology page.
CMS star ratings are a useful guide, not a guarantee. Always visit a home in person before you decide.
