Funding for this research was provided by:
Ministry of Defense, Singapore
Text and Data Mining valid from 2018-03-12
Received: 3 November 2017
Accepted: 4 March 2018
First Online: 12 March 2018
Ethics approval and consent to participate
: The study was reviewed and approved by DSO-SAF Institutional Review Board. Informed consent has been obtained in writing from each participant.
: Not applicable, as the manuscript does not contain data from any individual person.
: The authors declare that they have no competing interests.
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