Funding for this research was provided by:
Ministry of Higher Education, Malaysia (203/PPSP/6770003, UPM/700-2/1/LRGS/5526400)
Universiti Putra Malaysia
Received: 16 August 2018
Accepted: 15 May 2019
First Online: 22 May 2019
Ethics approval and consent to participate
: The informed written consent was obtained from every respondent before the survey. Personal data and other information were kept confidential and the results did not identify the respondents personally. Ethical clearance and a return consent form were obtained from the Medical Research Ethics Community of Faculty of Medicine and Health Sciences, Universiti Putra Malaysia (reference: UPM/TNCPI/RMC/22.214.171.124.1(JKEUPM)/F2).
: Not applicable.
: The authors declare that they have no competing interests.
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