Funding for this research was provided by:
Major Research Plan (81470369)
Received: 11 October 2018
Accepted: 11 December 2018
First Online: 20 December 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 (HKU/HA HKW IRB, IRB Reference Number: UW 05–269 T/932) with informed consents.
: Not applicable.
: The authors declare that they have no competing interests.
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