Article History
First Online: 26 June 2018
Compliance with Ethical Standards
:
: This study was funded by National Medical Research Council, Singapore (NMRC/EDG/0063/2009).
: This study was approved by the Singapore Health Services Institutional Review Board and has been performed in accordance with the ethical standards of the Declaration of Helsinki.
: Written informed consent was provided by the patients who agreed to participate in this study.
: CFL, RN, NL and YBC have no potential conflicts of interest.