Funding for this research was provided by:
National Medical Research Council (HSRG/0034/2013)
Received: 26 September 2018
Accepted: 26 April 2019
First Online: 8 May 2019
Ethics approval and consent to participate
: The SingHealth Centralised Institutional Board approved this research (Ref No: 2014/916/A) and written informed consent was provided before recruitment into the study.
: Not applicable.
: All authors disclose there is no conflict of interest in production of this manuscript.
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