Article History
Received: 2 November 2019
Accepted: 14 October 2020
First Online: 5 November 2020
Ethics approval and consent to participate
: This study was approved by the Human Subjects Ethics Application Review System of The Hong Kong Polytechnic University (HSEARS20170227009). Written informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.