Document is current

Article History

Received: 11 January 2019

Accepted: 22 April 2019

First Online: 21 May 2019

Ethics approval and consent to participate

: All survey protocol and instruments were approved by the Institutional Review Board of the Hanoi School of Public Health in 2016. All participants provided informed verbal consent after receiving information about the purpose of the study and their rights, which was well documented by a surveyor. Verbal consent was also approved by the ethics committee. Verbal consent was chosen over written consent to avoid potential issues with literacy and because they are suspicious of signing a document. The participants were informed that they could refuse to participate or choose to withdraw from a survey at any time. Confidentiality was assured by coding the participants’ responses.

: Not applicable.

: The authors declare that they have no competing interests.

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