Text and Data Mining valid from 2018-05-11
Received: 21 December 2017
Accepted: 26 April 2018
First Online: 11 May 2018
Ethics approval and consent to participate
: Ethical approval for this study and a waiver for informed consent were obtained from SingHealth Centralized Institutional Review Board (Reference no.: 2016/2198).
: The authors declare that they have no competing interests.
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