Funding for this research was provided by:
National University of Singapore (AG-2014-001)
Article History
Received: 13 November 2019
Accepted: 28 February 2020
First Online: 12 March 2020
Ethics approval and consent to participate
: This study was conducted according to the guidelines in the Declaration of Helsinki and all procedures involving human subjects/patients were approved by the National University of Singapore Institutional Review Board Reference Code: N-17-011. Written informed consent was obtained from all subjects.
: Not applicable.
: The authors declare that they have no competing interests.