Received: 1 August 2016
Accepted: 16 January 2018
First Online: 25 January 2018
Ethics approval and consent to participate
: Ethical approval to undertake this study was applied before starting the data collection in July 2014. Ethical approval was officially obtained from the Ethics Committee at the Universiti Kebangsaan Malaysia on 19 May 2014 (Reference Number: UKM.220.127.116.11/224/UNU-003-2014).
: Not applicable
: The authors declare that they have no competing interests.
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