[1] Rutgers State Univ, Robert Wood Johnson Med Sch, New Brunswick, NJ USA
[2] Kaiser Permanente, Dept Gastroenterol, Los Angeles, CA USA
[3] Weill Cornell Med Coll, New York, NY USA
[4] Hosp Juarez, Dept Gastroenterol, Mexico City, DF, Mexico
[5] Santander Hosp, Dept Gastroenterol, Reynosa, Mexico
[6] Mexican Hosp, Dept Gastroenterol, Mexico City, DF, Mexico
[7] Alfa Inst Gastroenterol, Clin Hosp, Bela Horizonte, Brazil
[8] Univ Sao Paulo, Gastrointestinal Endoscopy Unit, Med Sch, Sao Paulo, Brazil
[9] Cent Hosp Policia, Div Gastroenterol, Bogota, Colombia
[10] Mil Hosp Managua, Dept Gastroenterol, Managua, Nicaragua
[11] Clin Hosp, Dept Gastroenterol, Div Gastroenterol, Caracas, Venezuela
[12] Equatorian Inst Digest Dis, Dept Gastroenterol, Guayaquil, Ecuador