Text and Data Mining valid from 2018-10-22
Received: 24 April 2018
Accepted: 11 October 2018
First Online: 22 October 2018
Ethics approval and consent to participate
: The study was approved by Siriraj Institutional Review Board with certificate of approval number Si 328/2017. Informed consents were waived.
: Not applicable
: The authors declare that they have no competing interests.
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