Received: 5 April 2017
Accepted: 22 February 2018
First Online: 27 February 2018
Ethics approval and consent to participate
: Ethical approval for the study was obtained from the Ethics Review Committee of the Faculty of Medicine, University of Colombo, Sri Lanka.Written consent of a parent and assent from the subjects were obtained for all participants before distribution of the study questionnaires.
: Not applicable
: None of the authors have any competing interests.
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