Properties of the overall hospital Star Ratings and consumer choice

To examine characteristics of the CMS Overall Hospital Quality Star Ratings related to their use by consumers for choosing hospitals.

Observational study using secondary data analyses.

Hospital Star Rating data reported in February 2019 and additional quality data from California and New York were used, with a mix of analytical approaches including descriptive statistics, correlational analysis, and Poisson regression models.

The distribution of hospitals' Star Rating summary scores was tightly compressed, with no hospitals at or near the scores that would be obtained if a hospital were either best or worst across all quality domains. Hospitals did not consistently perform well or poorly across the range of measures and quality groups included in the Star Ratings. On average, for a given quality measure included in the Star Rating program, 12% of 1-star hospitals received top-quartile scores and 16% of 5-star hospitals received bottom-quartile scores. No significant associations were found between hospitals' overall Star Ratings and their performance on a set of condition-specific quality measures for hospitals in California and New York State.

Hospitals' overall scores clustered in the middle of the potential distribution of scores; no hospitals were either best at everything or worst at everything. The Star Ratings did not predict hospital quality scores for separate quality measures related to specific medical conditions or health care needs. These 2 observations suggest that the Star Ratings are of limited value to consumers choosing hospitals for specific care needs.