Funding for this research was provided by:
Universiti Kebangsaan Malaysia (DIP-2013-003, DIP-2015-004)
Received: 3 May 2018
Accepted: 22 November 2018
First Online: 29 November 2018
Ethics approval and consent to participate
: Ethical approval was obtained from UKM Ethical Committee with the approval code: FF-249-2012. Sample collection was conducted according to the UKM Guidelines for Ethical Review of Clinical Research or Research Involving Human subjects 2014. Written informed consent was provided to the participants’ parents.
: Not applicable.
: The authors declare that they have no competing interests.
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