Table 1.

Summary of Surgeon and Hospital Volume Groups Over the Study Period

Variable	Low	Medium	High	Very high
Surgeons
Definition of group*	<5	5–11	>11	–
Surgeons, n	1,274	379	64	–
Cases, † n	3,916	7,038	6,975	–
Hospitals
Definition of group*	<9	9–18	19–37	>37
Hospitals, n	49	48	46	50
Cases, † n	575	2,033	4,046	11,095

^*Average number of colectomies for cancer per year.

^†Total number of cases over the study period.