Funding for this research was provided by:
National Medical Research Council (NMRC-HSRG-0060-2016)
National University of Singapore (AG-2014-001)
Received: 11 September 2018
Accepted: 29 January 2019
First Online: 7 February 2019
Ethics approval and consent to participate
: This study protocols and procedures are in accordance with the Declaration of Helsinki and were approved by the National University of Singapore Institutional Review Board Reference Code: S-17-172. Written informed consent was obtained from all subjects.
: Not Applicable.
: The authors declare that they have no competing interests.
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