Funding for this research was provided by:
Ministry of Higher Education, Malaysia (ERGS/1/2012/SKK03/UKM/02/1)
University Research Grant UKM (GUP-2013-23)
Text and Data Mining valid from 2019-02-04
Received: 21 February 2018
Accepted: 17 January 2019
First Online: 4 February 2019
Compliance with ethical standards
: The authors declare that they have no competing interest.
: Prior ethical approval was obtained from the Research and Ethical Committee of Faculty of Medicine, Universiti Kebangsaan Malaysia (FF-2015-235).
: All the human study subjects provided informed consent.