Chan, Mark
Wong, Matthew
Leung, Ronnie
Cheung, Steven
Blanck, Oliver
Article History
Received: 20 March 2017
Accepted: 29 January 2018
First Online: 9 February 2018
Ethics approval and consent to participate
: The study was approved by the New Territories West Cluster Clinical and Research Ethics Committee (reference number: NTWC/CREC/15138) and ethics approval was not required.
: N/A
: The authors declare that they have no competing interest.
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