Funding for this research was provided by:
National Medical Research Council (NMRC/CSA-SI/0005/2015)
Received: 20 October 2017
Accepted: 22 February 2018
First Online: 14 March 2018
Ethics approval and consent to participate
: Ethical approval has been obtained from the SingHealth Ethics Review Committee for the original protocol as well as the amendments. Written informed consent will be obtained prior to participant involvement in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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