Text and Data Mining valid from 2018-10-12
Received: 11 June 2018
Accepted: 1 October 2018
First Online: 12 October 2018
Ethics approval and consent to participate
: This study was reviewed and approved by the Ethical Review Committee for Human Research, Faculty of Public Health, Mahidol University (MUPH 2017–068). All participants provided their written informed consent before enrollment. All data were collected anonymously.
: Not applicable.
: The authors declare that they have no competing interests.
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