The Centers for Medicare & Medicaid Services’ uses a five star rating system to grade nursing homes, based on the following areas: nursing home staffing, quality measures and health inspections.

The results of a recent study conducted by the CMS shows that the quality of care in U.S. nursing homes is improving. In evaluating the scores of 15,000 skilled nursing facilities across the country,found that the proportion of 4- and 5-Star centers has increased 4% and 4.1%, respectively. Meanwhile, the proportion of 1-Star facilities fell 7%. The data was released late last week.

The reason for the decline of 1-Star facilities is not entirely clear to officials at the American Health Care Association. But AHCA President and CEO Mark Parkinson said he was “excited about this positive trend, and will continue to work with CMS to do more in these critical areas.”