Funding for this research was provided by:
National Cancer Center of Korea (NCC-1310270; NCC-1610410)
Received: 14 July 2016
Accepted: 7 March 2018
First Online: 15 March 2018
Ethics approval and consent to participate
: This study was approved by the National Ethics Committee for Health Research in Cambodia. All study participants provided written informed consent before the survey.
: Not applicable.
: The authors declare that they have no competing interests.
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