[1] Univ Pittsburgh, Grad Sch Publ Hlth, Natl Surg Adjuvant Breast & Bowel Project Operat, Pittsburgh, PA USA
[2] Univ Pittsburgh, Grad Sch Publ Hlth, Ctr Biostat, Pittsburgh, PA USA
[3] Univ Pittsburgh, Grad Sch Publ Hlth, Dept Biostat, Pittsburgh, PA USA
[4] Allegheny Gen Hosp, Pittsburgh, PA 15212 USA
[5] Univ Pittsburgh, Inst Canc, Div Hematol Oncol, Pittsburgh, PA USA
[6] Univ Pittsburgh, Dept Med, Pittsburgh, PA USA
[7] Columbus Community Clin Oncol Program, Columbus, OH USA
[8] Helen F Graham Canc Ctr, Dept Surg, Newark, DE USA
[9] Univ Sydney, Australasian Gastrointestinal Trials Grp, Sydney, NSW 2006, Australia
[10] Atlanta Canc Care, Atlanta, GA USA
[11] SW Canc Control Consortium, Goldsboro, NC USA
[12] Wake Forest Univ, Surg Oncol Serv, Winston Salem, NC 27109 USA
[13] Franklin Sq Hosp Ctr, Harry & Jeanette Weinberg Canc Inst, Div Surg Oncol, Baltimore, MD USA
[14] Canc Res Ozarks CCOP, Springfield, MO USA
[15] Kaiser Permanente No Calif, Dept Hematol Oncol, Vallejo, CA USA
[16] Michigan State Univ, Dept Med, Div Hematol Oncol, E Lansing, MI 48824 USA
[17] Metro Minnesota CCOP, Minneapolis, MN USA
[18] CCOP Missouri Valley Canc Consortium, Omaha, NE USA
[19] NW CCOP, Tacoma, WA USA
[20] Columbia River Oncol Program, Portland, OR USA