Text and Data Mining valid from 2020-03-12
Received: 8 December 2019
Accepted: 18 February 2020
First Online: 12 March 2020
Ethics approval and consent to participate
: This study was ethically and scientifically reviewed and approved by Hanoi Medical University according to Decision No. 5403/QD-DHYHN dated 06/12/2016. All participants received information of the purpose and methods and their right to refuse participation at any time. We obtained their verbal informed consent as the principal investigator is currently working at this hospital and all participants agreed to support the study and as this study is part of research agenda of the hospital to improve healthcare quality. They were re-affirmed that their participation was voluntary, that their anonymity was maintained, and that their refusal would not affect their health care.
: The authors declared no competing interests on the authorship and publication of this article.