[1] Johns Hopkins Med Inst, Div Gastroenterol, Baltimore, MD 21205 USA
[2] Radboud Univ Nijmegen, Med Ctr, Dept Gastroenterol & Hepatol, Nijmegen, Netherlands
[3] Johns Hopkins Bloomberg Sch Publ Hlth, Dept Biostat, Baltimore, MD USA
[4] Sidney Kimmel Comprehens Canc Ctr, Dept Oncol, Div Biostat & Bioinformat, Baltimore, MD USA
[5] Univ Pittsburgh, Med Ctr, Div Gastroenterol & Hepatol, Pittsburgh, PA USA
[6] Med Univ South Carolina, Div Gastroenterol & Hepatol, Charleston, SC 29425 USA
[7] Asian Inst Gastroenterol, Dept Gastroenterol, Hyderabad, India
[8] Apollo Gleneagles Hosp, Dept Gastroenterol, Kolkata, India
[9] Postgrad Inst Med Educ & Res, Dept Gastroenterol, Chandigarh, India