Funding for this research was provided by:
Universiti Putra Malaysia (9409800, 9432700)
Text and Data Mining valid from 2019-02-22
Received: 15 November 2018
Accepted: 17 February 2019
First Online: 22 February 2019
Ethics approval and consent to participate
: This study was approved by Universiti Putra Malaysia (UPM), Universiti Kebangsaan Malaysia (UKM) ethics committee and Medical Research Ethics Committee (MREC), Ministry of Health, Malaysia (MOH). This study was registered with the National Medical Research Registry with the registration number NMRR-14-1176-21475.
: Not applicable.
: The authors declare that they have no competing interests.
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