Here’s how CMS calculates the Overall Hospital Rating

In July 2016, a new star was born when CMS (The Centers for Medicare & Medicaid Services) added the Overall Hospital Quality Star Rating to its Hospital Compare website. According to CMS, star ratings make it easier for healthcare consumers to compare hospitals by assigning more stars to hospitals that have achieved higher scores on the 11 dimensions measured by the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) Survey.

The idea behind the Overall Hospital Quality Star Rating is simple: it combines seven areas of quality into a single score that consumers can use — along with their physician’s recommendation — to decide where to receive care. CMS, working with input from a wide range of stakeholders, developed the methodology used to calculate the Overall Hospital Rating.

How is the Overall Hospital Quality Star Rating calculated?’

The Overall Hospital Rating factors as many as 57 quality measures into its rating formula, even though the average number of measures on which a single hospital is evaluated ends up being around 39. Not every hospital generates data for all 57 quality measures. Once an individual hospital satisfies its reporting threshold, its overall rating can only be determined using measures for which data are available.

Those 57 quality measures are spread across seven areas of quality:

  1. Mortality
  2. Safety of Care
  3. Readmission
  4. Patient Experience
  5. Effectiveness of Care
  6. Timeliness of Care
  7. Efficient Use of Medical Imaging

And each area of quality is weighted in the Overall Hospital Rating calculation.

2017 Hospital Compare Overall Rating BP Measure Weight Calc Graphic.png

From: How measure categories are weighted

To earn an Overall Hospital Quality Star Rating, a hospital must measure at least three categories of quality, including at least one outcome group (Mortality, Safety, or Readmission). Because not every hospital reports every measure, not every hospital is eligible to receive an overall rating. If a hospital doesn’t measure every area of quality, CMS redistributes the weights among the qualifying measures for which it does collect data.

So, what are the odds of earning 5 Stars?

Based on December 2016 data, here’s the national distribution of the Overall Hospital Quality Star Rating:

2017 Hospital Compare Overall Rating BP Distribution Chart.png

From: How the Hospital Compare overall rating is calculated

Every qualifying hospital receives an individualized quarterly report from CMS that is distributed through QualityNet, CMS’s portal for facilitating the secure exchange of quality performance data among hospitals, physicians’ officers, nursing homes and other qualified facilities and vendors. Although CMS will continue to produce these individual quarterly reports, it is changing how it will report the Overall Hospital Quality Star Rating.

How is CMS changing the way it reports the Overall Hospital Quality Star Rating?

It’s not a big deal, really. CMS will continue to update Hospital Compare every quarter, and hospital leaders can access their individualized preview reports through QualityNet. But CMS will only calculate and report the Overall Hospital Quality Star Rating twice a year, in July and December. CMS is making the switch to biannual reporting because the differences in hospitals’ quality ratings from quarter to quarter have actually proved to be quite small. Biannual reporting promises to be more meaningful and more efficient.

If you have any questions about these important changes to a very visible consumer resource that’s growing more and more popular, be sure to ask Jan Gnida, Director of Patient Experience & Government Surveys, or Laura VanEpps, CAHPS Project Coordinator, using the form you’ll land on when you click the Contact Us link. In the meantime, remember that you can always count on PRC to help you catch a falling star and bring it back to where it belongs. To learn more about how PRC can help you design and conduct research studies that can put you on the road to performance improvement, just Contact Us.