Article History
First Online: 25 January 2018
Compliance with Ethical Standards
:
: The authors declare that they have no conflict of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study was approved by National University of Singapore’s institutional review board.
: Informed consent was obtained from all individual participants included in the study.