Received: 30 October 2019
Accepted: 27 November 2019
First Online: 4 December 2019
Ethical approval and consent to participate
: Ethical approval was obtained from Institutional ethical review board of the Institute of public health, College of Medicine and health sciences, University of Gondar. Support letter was obtained from Gondar town trade and industry office.
: Not applicable.
: The authors declare that they have no competing interests.