Received: 17 July 2020
Accepted: 19 August 2020
First Online: 31 August 2020
Ethics approval and consent to participate
: The protocol of this research was approved by the Institutional Review Board of Vietnam Military Medical University (number: 251/2019) and by the local ethics committees of two participating centers (Military Hospital 103 Ethics Committee; National Lung Hospital Ethics Committee). All participants had provided written informed consents for this study.
: Not applicable.
: The authors declare that they have no competing interests.