Funding for this research was provided by:
University Research Committee, University of Hong Kong (14104614, TBF16ENG007 and TBF17MED002)
Text and Data Mining valid from 2018-12-01
Received: 22 July 2018
Accepted: 28 November 2018
First Online: 28 December 2018
Ethics approval and consent to participate
: Not applicable
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