Received: 25 February 2017
Accepted: 29 May 2018
First Online: 7 June 2018
Ethics approval and consent to participate
: Ethics approval was obtained from the Ethics Review Committee (ERC) of the Faculty of Medical Sciences, of University of Sri Jayewardenepura (2015/Aug). Written informed consent was obtained from participants before including them in the study.
: The authors declare that they have no competing interests.
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