Funding for this research was provided by:
Dean of the Faculty of Arts and Sciences, Dartmouth College (061/2559)
Text and Data Mining valid from 2019-11-11
Received: 2 June 2019
Accepted: 25 October 2019
First Online: 11 November 2019
Ethics approval and consent to participate
: This follow-up study was approved by the Research Ethics Committee 4, The certificate of Approval Number 159/2015. Faculty of Medicine, Chiang Mai University. Written informed consent was obtained before enrollment.
: Not applicable.
: The authors declare that they have no competing interests.