Funding for this research was provided by:
National Medical Research Council (NMRC/TA/0031/2015)
National Institutes of Health (NIH R01 CA144034, UM1 CA182876)
Received: 23 August 2017
Accepted: 15 November 2017
First Online: 28 November 2017
Ethics approval and consent to participate
: Written informed consent was obtained from participants upon enrolment. The SingHealth Centralised Institutional Review Board had approved the study protocol (2014/628/C).
: The authors declare that they have no competing interests.
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