[1] Mayo Clin Hlth Syst, Div Gastroenterol & Hepatol, Eau Claire, WI USA
[2] St Peters Univ Hosp, Div Gastroenterol, New Brunswick, NJ USA
[3] Univ Pittsburgh, Grad Sch Publ Hlth, Dept Biostat, Pittsburgh, PA 15213 USA
[4] Univ Florida, Dept Hlth Outcomes & Biomed Informat, Gainesville, FL USA
[5] Kaiser Permanente Los Angeles Med Ctr, Div Gastroenterol, Ctr Pancreat Care, Los Angeles, CA USA
[6] Univ Florida, Div Gastroenterol Hepatol & Nutr, Gainesville, FL USA
[7] Univ Pittsburgh, Med Ctr, Div Gastroenterol & Hepatol, 200 Lothrop St,M2,C Wing, Pittsburgh, PA 15213 USA