Funding for this research was provided by:
Ministry of Higher Education (MOHE), Malaysia under the High Impact Research (HIR)-MOHE (E000013-20001)
University of Malaya Research Grant (RP013C-13HTM)
Received: 22 June 2018
Accepted: 31 August 2018
First Online: 5 September 2018
Ethics approval and consent to participate
: Ethical approval to conduct this study was obtained from the Medical Ethics Committee of University Malaya Medical Center (UMMC) (Ethics reference number: 1198.45).
: Consent for publication was obtained from the parents.
: The authors declare that they have no competing interests
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