Received: 18 December 2018
Accepted: 31 July 2019
First Online: 27 August 2019
Ethics approval and consent to participate
: Ethical clearance of this study was obtained from the Research Ethics Committee of School of Public Health and Institutional Review Board of College of Health Science, Addis Ababa University. Written informed consent was taken from all participants. Confidentiality and anonymity of the participants was kept.
: Not applicable.
: The authors declare that they have no competing interest.