Funding for this research was provided by:
National Research Council Sri Lanka (15-023)
Faculty Research Grants, Faculty of Medicine, University of Ruhuna, Sri Lanka (none)
Received: 2 December 2019
Accepted: 22 April 2020
First Online: 6 May 2020
Ethics approval and consent to participate
: Ethical clearance for the study was obtained from the ethical review committee, Faculty of Medicine, University of Ruhuna, Sri Lanka. Informed written consent was obtained from each participant prior to the commencement of the study.
: Not applicable.
: The authors declare that they have no competing interests<b>.</b>