Funding for this research was provided by:
National Medical Research Council Singapore (NMRC/CIRG/1386/2014)
Received: 4 July 2017
Accepted: 10 January 2018
First Online: 19 January 2018
Ethics approval and consent to participate
: This study was approved by SingHealth Institutional Ethics Review Board before commencement (CIRB 2014/754/B), and was carried out in accordance with the ethical principles as set out in the Declaration of Helsinki. Written consent was obtained from all the participants in the study.
: Not applicable in this section.
: The authors declare that they have no competing interests.
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