Table 1.

Characteristics of patients included and excluded in full chart review

	Included	Excluded
n (%)	1,924 (40%)	2,884 (60%)
Sex: males	1,066 (55.4%)	1,546 (53.6%)
Age, years (mean)	67.4	67.4
Urban residence	1,628 (84.6%)	2,431 (84.3%)
Tumor site colon	1,388 (72.1)	2,128 (73.8%)