Funding for this research was provided by:
Hong Kong Cancer Fund
General Research Fund of the Research Grant Council of Hong Kong (746710)
Received: 16 June 2016
Accepted: 31 January 2018
First Online: 7 February 2018
Ethics approval and consent to participate
: This study was reviewed and approved by the Institute of Review Board of the University of Hong Kong.Each potential participate was given an explanation of the study and written consent was obtained from those who agreed to participate.
: Not applicable.
: The authors declare that they have no competing interests.
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