Funding for this research was provided by:
Kansai Medical University
Received: 13 January 2021
Accepted: 12 April 2021
First Online: 21 April 2021
: This study was approved by the National Ethics Committee for Health Research, Ministry of Health, Lao PDR (reference no. 072-2017/NECHR).
: Not applicable
: The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper.