Seung Han Kim, Hoon Jai Chun, Hyuk Soon Choi, Eun Sun Kim, Bora Keum, Yoon Tae Jeen, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Institute of Gastrointestinal Medical Instrument Research, Korea University College of Medicine, Seoul 02841, South Korea
Author contributions: Kim SH and Chun HJ designed the study; Kim ES and Jeen YT assisted in creating the tables and figures; Choi HS and Keum B analyzed the data; and Kim SH wrote the manuscript.
Supported by Korea Health Technology R and D Project through the Korea Health Industry Development Institute; and Ministry of Health and Welfare, South Korea, No. HI14C3477.
Conflict-of-interest statement: Seung Han Kim, Hoon Jai Chun, Hyuk Soon Choi, Eun Sun Kim, Bora Keum and Yoon Tae Jeen have no conflicts of interest or financial ties to disclose.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Hoon Jai Chun, MD, PhD, AGAF, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Institute of Gastrointestinal Medical Instrument Research, Korea University College of Medicine, 126-1, Anam-dong 5 ga, Seongbuk-gu, Seoul 02841, South Korea. firstname.lastname@example.org
Telephone: +82-2-9206555 Fax: +82-2-9531943
Received: March 27, 2016
Peer-review started: March 28, 2016
First decision: April 14, 2016
Revised: April 28, 2016
Accepted: May 21, 2016
Article in press: May 23, 2016
Published online: June 28, 2016