Text and Data Mining valid from 2018-08-29
Received: 20 April 2018
Accepted: 15 August 2018
First Online: 29 August 2018
Ethics approval and consent to participate
: This study has been approved by the Institutional Review Board of Singapore General Hospital. The need for patient consent has been waived by the Institutional Review Board of Singapore General Hospital in view of the retrospective nature of the study.
: Not applicable.
: The authors declare that they have no competing interests.
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