[1] Mayo Clin, Div Gastroenterol & Hepatol, 200 First St SW, Rochester, MN 55905 USA
[2] Mayo Clin, Div Cardiovasc Dis, Rochester, MN USA
[3] Mayo Clin, Div Biomed Stat & Informat, Rochester, MN USA
[4] Mayo Clin, Div Hlth Care Policy & Res, Rochester, MN USA
[5] Mayo Clin, Robert D & Patricia E Kern Ctr Sci Hlth Care Deli, Rochester, MN USA