How CMS star ratings work
CMS rates each certified nursing home from one to five stars in three domains and combines them into an overall rating. The ratings are CMS's; this site shows them as published.
Health inspections
Based on the three most recent standard surveys and the complaint and infection-control inspections in the same periods, weighted toward the most recent cycle and toward more severe citations. Because the score is ranked within each state, the same record can rate differently in different states.
Staffing
Based on nurse hours per resident per day from payroll data, adjusted for how much care residents need (case mix), with separate consideration of registered-nurse hours, weekend staffing and turnover.
Quality measures
Based on resident-assessment (MDS) and claims measures such as falls with injury, pressure ulcers, antipsychotic use and hospital readmissions, split into long-stay and short-stay measures.
How they combine
The health inspection rating is the starting point. A staffing rating of four or five adds a star; one star removes one. A quality-measure rating of five adds a star; one removes one. The overall rating cannot exceed five or, for Special Focus Facilities, be raised above the inspection rating.
What the rating leaves out
- It does not describe any individual resident's experience, and it lags the underlying surveys.
- Fines and payment denials are shown separately on Care Compare and on this site; they are not part of the star calculation.
- Ownership changes and chain membership are not rated.
CMS describes the method in its Five-Star Quality Rating System Technical Users' Guide.