Article History
Received: 27 November 2018
Accepted: 20 June 2019
First Online: 4 July 2019
Ethics approval and consent to participate
: The corresponding author’s Institutional Review Board (Singapore General Hospital, Singapore Health Services) granted ethical approval for this retrospective study, reference number 2014/155/D, with waiver of informed consent granted as only secondary retrospective and de-identified data was used.
: Not applicable
: The authors declare that they have no competing interests.