Document is current

Article History

Received: 6 October 2018

Accepted: 14 November 2018

First Online: 3 December 2018

Ethics approval and consent to participate

: Ethical approval was given by the first author’s (Singapore General Hospital) Institutional Review Board and all data was de-identified and analysed on password-protected computers. Consent was not obtained because information was anonymized and de-identified prior to analysis as per National Registry of Diseases Office protocol.

: Not applicable.

: The authors declare that they have no competing interests.

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