[1] Ctr Dis Control & Prevent, Div Canc Prevent & Control, Atlanta, GA USA
[2] Amer Canc Soc, Atlanta, GA 30329 USA
[3] Ctr Medicare Serv, Chron Care Policy Grp, Baltimore, MD USA
[4] Ctr Medicaid Serv, Chron Care Policy Grp, Baltimore, MD USA
[5] Harvard Univ, Sch Med, Dept Ambulatory Care, Boston, MA USA
[6] Harvard Univ, Sch Med, Dept Prevent Epidemiol & Social Med, Boston, MA USA
[7] Univ Penn, Penn Presbyterian Med Ctr, Dept Med Imaging, Philadelphia, PA 19104 USA
[8] Mayo Clin, Dept Radiol, Rochester, MN USA
[9] Kaiser Permanente Med Ctr, Dept Gastroenterol, Walnut Creek, CA USA
[10] Louisiana State Univ, Hlth Sci Ctr, Dept Family Med, Shreveport, LA 71105 USA
[11] Univ Calif San Francisco, San Francisco, CA 94143 USA
[12] Univ N Carolina, Dept Med, Chapel Hill, NC USA
[13] Indiana Univ, Sch Med, Div Gastroenterol, Indianapolis, IN USA
[14] Univ Pittsburgh, Sch Med, Div Gastroenterol Hepatol & Nutr, Pittsburgh, PA USA
[15] Boston Univ, Sch Med, Gastroenterol Sect, Boston, MA 02118 USA
[16] Mem Sloan Kettering Canc Ctr, Dept Med, Serv Gastroenterol & Nutr, New York, NY 10021 USA
[17] St Marks Hosp, Canc Res UK, Colorectal Canc Unit, Harrow, Middx, England
[18] Oregon Hlth & Sci Univ, Div Gastroenterol, Portland, OR 97239 USA