Received: 20 February 2018
Accepted: 16 April 2018
First Online: 25 April 2018
Ethics approval and consent to participate
: Ethical clearance was obtained from the Institutional Review Board of the University of Gondar. Official letters of co-operation submitted to all primary, secondary schools and city administration education office. Students and their parents were notified and necessary explanations were also given about the purposes, procedure and ethical issues of the study. Consent was collected from the parents of study subjects by sending letter to parent/guardians for each study subject less than 18 years old and oral assent was also obtained from study subjects in the school. The purpose of the study was explained and written informed consent was secured. Confidentiality was maintained at all levels of the study. Participant’s involvement in the study was on voluntary basis; participants who were not volunteer to participate in the study and those who wish to quit their participation at any stage were informed to do so without any restriction. The respondents’ confidentiality of information was assured by excluding names and identifiers from in the questionnaire.
: The authors declare that they have no competing interest.
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