[1] Univ N Carolina, Sch Med, Div Digest Dis, Ctr Esophageal Dis & Swallowing, Chapel Hill, NC USA
[2] Columbia Univ, Med Ctr, New York, NY USA
[3] Northwestern Univ, Chicago, IL 60611 USA
[4] Gastrointestinal Associates, Knoxville, TN USA
[5] St Thomas Hosp, Nashville, TN USA
[6] Vanderbilt Univ, Sch Med, Nashville, TN 37212 USA
[7] Dartmouth Hitchcock Med Ctr, Lebanon, NH 03766 USA
[8] Stanford Univ, Sch Med, Palo Alto, CA 94304 USA
[9] Mayo Clin Florida, Jacksonville, FL USA
[10] Atlanta Gastroenterol Associates, Atlanta, GA USA
[11] Univ Texas Hlth, Houston, TX USA
[12] Rush Univ, Med Ctr, Chicago, IL 60612 USA
[13] Sisters Charity Hosp, Buffalo, NY USA
[14] Sarasota Mem Hosp, Sarasota, FL USA
[15] Univ Calif Los Angeles, Med Ctr, Orange, CA USA
[16] Thomas Jefferson Univ, Philadelphia, PA 19107 USA