Received: 21 September 2019
Accepted: 20 February 2020
First Online: 6 March 2020
Ethics approval and consent to participate
: Ethical approval for this study has been obtained from National Healthcare Group Singapore Domain Specific Review Board (Study Reference No: 2018/00630). Waiver of consent has been approved.
: Not Applicable.
: The authors declare that they have no competing interests.