[1] Univ Michigan, Div Gastroenterol, Ann Arbor, MI 48109 USA
[2] Johns Hopkins Univ, Data Coordinating Ctr, Baltimore, MD USA
[3] Temple Univ, Gastroenterol Sect, Philadelphia, PA 19122 USA
[4] Johns Hopkins Univ, Gastroenterol Sect, Baltimore, MD USA
[5] Wake Forest Univ, Gastroenterol Sect, Winston Salem, NC 27109 USA
[6] Univ Louisville, Div Gastroenterol, Louisville, KY 40292 USA
[7] Texas Tech Univ, Gastroenterol Sect, El Paso, TX USA
[8] Stanford Univ, Div Gastroenterol, Palo Alto, CA 94304 USA
[9] Calif Pacific Med Ctr, Div Gastroenterol, San Francisco, CA USA
[10] Mayo Clin, Sect Gastroenterol, Rochester, MN USA
[11] Metrohlth Med Ctr, Endocrinol Sect, Cleveland, OH USA
[12] Johns Hopkins Univ, Sect Gastroenterol, Data Coordinating Ctr, Baltimore, MD USA
[13] NIDDK, Bethesda, MD USA