Variation in Postoperative Outcomes Across Federally Designated Hospital Star Ratings

Importance: Despite widespread use to guide patients to hospitals providing the best care, it remains unknown whether Centers for Medicare 95% CI, 1.73-2.00). There was wide variation in the rates of hospital mortality (variation, 1.89%; range, 2.4%-16.2%), serious complications (variation, 1.97%; range, 5.5%-45.1%), and readmission (variation, 1.27%; range, 9.1%-22.5%) across all hospitals. After stratifying hospitals by their star rating, similar patterns of variation were observed within star rating groups for 30-day mortality: 1 star (variation, 1.91%; range, 3.6%-12.0%), 2 star (variation, 1.86%; range, 2.8%-16.2%), 3 star (variation, 1.84%; range, 2.9%-12.3%), 4 star (variation, 1.76%; range, 2.9%-11.5%), and 5 star (variation, 1.79%; range, 2.4%-9.1%). Similar patterns were observed for serious complications and readmissions. Conclusion and Relevance: Although CMS hospital star rating was associated with postoperative mortality, serious complications, and readmissions, there was wide variation in surgical outcomes within each star rating group. These findings highlight the limitations of the CMS hospital star rating system as a measure of surgical quality and should be a call for continued improvement of publicly reported hospital grade measures.