Table 2.

Adjusted Association Between the Rank Categories and Patient’s Outcomes

Rank category	Risk-adjusted outcomes* (%)	95% confidence interval (%)	P-for-trend
30-day mortality rate
1–50	11.3	(10.9, 11.7)	< 0.001
51–100	11.9	(11.5, 12.2)
101–150	12.1	(11.8, 12.3)
151–200	12.1	(11.8, 12.5)
201 or lower	12.4	(12.3, 12.4)
30-day readmission rate
1–50	18.7	(18.4, 19.1)	0.004
51–100	18.5	(18.2, 18.8)
101–150	18.8	(18.5, 19.0)
151–200	18.9	(18.2, 19.5)
201 or lower	19.0	(19.0, 19.1)

*Adjusted for hospital size, teaching status, profit status, hospital region, rural/urban status, the presence of intensive care unit (ICU), and hospital referral region (HRR) fixed effects. Risk-adjusted outcomes were estimated using marginal standardization (also known as predictive margins or margins of responses). Our final sample consisted of 2212 hospitals for the analysis of mortality and 2040 hospitals for the analysis of readmission, after excluding hospitals with missing data on outcome or adjustment variables