Funding for this research was provided by:
Asia Pacific Observatory on Health Systems and Policies (2016/622444-0)
Received: 30 November 2017
Accepted: 20 December 2018
First Online: 7 January 2019
Ethics approval and consent to participate
: The ethical approval of this study has been granted by the Institutional Review Board at Duke Kunshan University in China (approval number: No. 2016ZHU010), Hanoi University of Public Health in Vietnam (approval number: No.016-292/DD-YTCC), and National Institute of Public Health in Cambodia (approval number: No.348NECHR). Each participant provided its written informed consent, and the anonymity of their information was respected during the whole research process.
: Not applicable.
: The authors declare that they have no competing interests.
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