Table 1.

Characterization of sites within the hospital system.

Community class	Volume class	Inclusion/exclusion reason
Urban	Very high-volume (80–100 k)	Included
Suburban	High-volume (60–80 k)	Included
Suburban	Average-volume (40–60 k)	Included
Suburban	Moderate-volume (20–40 k)	Included
Suburban	Moderate-volume (20–40 k)	Included
Rural	Moderate-volume (20–40 k)	Included
Rural	Low-volume (<20 k)	Included
Rural	Low-volume (<20 k)	Excluded, insufficient data prior to 2/28/2020
Rural	Low-volume (<20 k)	Excluded, insufficient data prior to 2/28/2020
Rural	Low-volume (<20 k)	Excluded, insufficient data prior to 2/28/2020