Received: 16 July 2020
Accepted: 11 November 2020
First Online: 23 November 2020
Ethics approval and consent to participate
: This study was conducted with the approval of Research Ethics Committee (REC) of Hong Kong Sanatorium & Hospital. The reference number is RC-2020-04. All personal identifiers were removed in the whole research process. Consent to participate: not applicable.
: Not applicable.
: The authors declare no competing interests.