Received: 5 October 2017
Accepted: 16 February 2018
First Online: 6 March 2018
Ethics approval and consent to participate
: The ethical clearance was approved by the Ethics Review Committee, Faculty of Medicine, University of Peradeniya, Sri Lanka. All participants were informed that their participation was voluntary and the procedure used did not pose any potential risk and their identities will be kept strictly confidential. Informed written consent forms were obtained from all the participants who volunteered to participate in the study and parental consent was obtained for all participants under the age of 18. All information was kept in confidence.
: Not applicable.
: The authors declare that they have no competing interests.
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