Table 1.

Patient selection and exclusion criteria.

Criteria	N	Percent of initially identified cases remaining in the analytic cohort
Stage I–III rectal adenocarcinoma patients treated with chemoradiation 1998–2007 (n=1982)	1982	100
Excluding patients with 2nd primary cancer diagnosis within 24 months (n=133)	1849	93
Excluding survival of less than 6 months after primary tumor resection (n=114)	1735	88
Excluding non-confirmed diagnosis or diagnosis noted on nursing/convalescent home/hospice, death certificate or autopsy report (n=4)	1731	87
Excluding age >80 (n=229)	1502	76
Excluding missing SES (n=10)	1492	75