Funding for this research was provided by:
University Research Committee, University of Hong Kong (17115916)
Article History
Received: 4 September 2018
Accepted: 8 November 2018
First Online: 20 November 2018
Ethics approval and consent to participate
: The study was approved by the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West Cluster (UW 15–178).
: Not applicable.
: The authors declare that they have no competing interests.
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