[1] Univ Calif San Francisco, Dept Med, Div Gastroenterol, San Francisco, CA 94115 USA
[2] Univ Calif San Francisco, Dept Epidemiol & Biostat, San Francisco, CA 94115 USA
[3] Vet Affairs Med Ctr, Dept Pathol, San Francisco, CA 94121 USA
[4] Exact Sci Corp, Marlborough, MA USA
[5] Indiana Univ, Sch Med, Dept Med, Div Gastroenterol, Indianapolis, IN USA
[6] Regenstrief Inst Inc, Indianapolis, IN USA