[1] Med Univ S Carolina, Div Gastroenterol & Hepatol, Charleston, SC 29425 USA
[2] Med Univ S Carolina, Ctr Digest Dis, Div Biometry & Epidemiol, Dept Med, Charleston, SC 29425 USA
[3] Med Univ S Carolina, Anxiety Disorders Program, Charleston, SC 29425 USA
[4] Med Univ S Carolina, Dept Clin Pharm & Outcome Studies, S Carolina Coll Pharm, Charleston, SC 29425 USA
[5] Univ N Carolina, Ctr Funct GI & Motil Disorders, Chapel Hill, NC USA
[6] Univ Alabama, Div Gastroenterol, Birmingham, AL 35294 USA
[7] Univ Michigan, Div Gastroenterol, Ann Arbor, MI 48109 USA
[8] Methodist Dallas Med Ctr, Dallas, TX USA
[9] Indiana Univ, Med Ctr, Div Gastroenterol & Hepatol, Indianapolis, IN USA
[10] Johns Hopkins Univ Hosp, Div Gastroenterol, Baltimore, MD 21287 USA
[11] Virginia Mason Med Ctr, Seattle, WA 98101 USA
[12] Univ Minnesota, Med Ctr, Div Gastroenterol, Minneapolis, MN 55455 USA
[13] NIDDK, Div Digest Dis & Nutr, Bethesda, MD USA