Funding for this research was provided by:
National Institutes of Health (AI036211)
National Research University Project under Thailand's Office of the Higher Education Commission
Received: 26 September 2016
Accepted: 4 April 2018
First Online: 11 April 2018
Ethics approval and consent to participate
: Three IRBs approved the study. These included the IRBs of: Research Institute for Health Sciences, Chiang Mai University; Faculty of Medicine, Khon Kaen University; and Faculty of Medicine, Chiang Mai University. Verbal informed consent was obtained from all participants prior to the interview. All IRBs allowed for verbal informed consent because of the non-sensitive nature of the study.
: The authors declare that they have no competing interests.
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