Funding for this research was provided by:
Chiang Mai University
Text and Data Mining valid from 2018-08-29
Received: 1 February 2018
Accepted: 20 August 2018
First Online: 29 August 2018
Ethics approval and consent to participate
: This study was approved by ethical research committee, Faculty of Medicine, Chiang Mai University. Reference number: FAC MED 2557 02493/ Research ID:2493.
: Not applicable.
: All of the authors declare no competing interests.
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