Navigating by Stars: Using CMS Star Ratings to Choose Hospitals for Complex Cancer Surgery

The Centers for Medicare and Medicaid Services (CMS) developed risk-adjusted "Star Ratings," which serve as a guide for patients to compare hospital quality (1 star = lowest, 5 stars = highest). Although star ratings are not based on surgical care, for many procedures, surgical outcomes are concordant with star ratings. In an effort to address variability in hospital mortality after complex cancer surgery, the use of CMS Star Ratings to identify the safest hospitals was evaluated.

Patients older than 65 years of age who underwent complex cancer surgery (lobectomy, colectomy, gastrectomy, esophagectomy, pancreaticoduodenectomy) were evaluated in CMS Medicare Provider Analysis and Review files (2013-2016). The impact of reassignment was modeled by applying adjusted mortality rates of patients treated at 5-star hospitals to those at 1-star hospitals (Peters-Belson method).

There were 105 823 patients who underwent surgery at 3146 hospitals. The 90-day mortality decreased with increasing star rating (1 star = 10.4%, 95% confidence interval [CI] = 9.8% to 11.1%; and 5 stars = 6.4%, 95% CI = 6.0% to 6.8%). Reassignment of patients from 1-star to 5-star hospitals (7.8% of patients) was predicted to save 84 Medicare beneficiaries each year. This impact varied by procedure (colectomy = 47 lives per year; gastrectomy = 5 lives per year). Overall, 2189 patients would have to change hospitals each year to improve outcomes (26 patients moved to save 1 life).

Mortality after complex cancer surgery is associated with CMS Star Rating. However, the use of CMS Star Ratings by patients to identify the safest hospitals for cancer surgery would be relatively inefficient and of only modest impact.