Funding for this research was provided by:
University of the Ryukyus, Organization for Research Promotion, Japan
Received: 17 December 2018
Accepted: 24 January 2019
First Online: 11 February 2019
Ethics approval and consent to participate
: This study was approved by the National Ethics Committee for Health Research, Ministry of Health, Lao PDR (no. 2017. 88. MC) and the Ethics Committee of the University of the Ryukyus, Japan (No. 169). Before starting the survey, surveyors explained to the participants the details of this study, such as its purpose, voluntary participation, information that would be collected, and how to keep and manage the data. Written informed consent was obtained from each respondent.
: Not applicable.
: The authors declare that they have no competing interests.
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