Received: 1 November 2018
Accepted: 30 April 2019
First Online: 17 May 2019
: SY (PhD) is Senior Research Fellow at Saw Swee Hock School of Public Health, National University of Singapore, Singapore and Director of KHANA Center for Population Health Research, Cambodia, SS (PhD) is Senior Research Fellow at KHANA Center for Population Health Research. ST (MA) is Manager,; PC (MPH) is Research Fellow; and SS (PhD) is Senior Advisor at KHANA Center for Population Health Research, Cambodia. SC (MHSc) is Senior Research Officer at FHI 360, Cambodia; PM (MPH) is Chief and NC (MPH) is Deputy Chief of Surveillance Unit, National Center for HIV/AIDS, Dermatology and STD; MP (PhD) is Senior Advisor for Research and Evaluation at Frontline AIDS, the United Kingdom.
: This study was approved by the National Ethics Committee for Health Research (NECHR) of the Ministry of Health, Cambodia (No. 420 NECHR). A written informed consent was obtained from each participant.
: Not applicable.
: The authors declare that they have no competing interests.
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