[1] Prince Songkla Univ, Internal Med, Hat Yai, Thailand
[2] Stanford Univ, Sch Med Gastroenterol & Hepatol, Stanford, CA USA
[3] Chulalongkorn Univ, Bangkok, Thailand
[4] Mahidol Univ, Siriraj Hosp, Salaya, Nakhon Pathom, Thailand
[5] Univ Malaya, Kuala Lumpur, Malaysia
[6] Natl Univ Singapore, Singapore, Singapore