Funding for this research was provided by:
The Gastroenterological Association of Thailand
Received: 21 April 2018
Accepted: 21 January 2019
First Online: 28 January 2019
Ethics approval and consent to participate
: This study was carried out according to the principles expressed in the Declaration of Helsinki and was approved by the Gastroenterological.Association of Thailand in collaboration with the NHSO, Thailand. All data were de-identified and released for research purposes therefore the consent form was not performed. The research protocol was approved by the Institutional Review Board of the Faculty of Medicine, Chulalongkorn University (IRB 113/58).
: Not applicable. No details, images, or videos relating to individual participants are included in the manuscript.
: The authors declare that they have no competing interests.
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