Received: 2 August 2018
Accepted: 6 December 2018
First Online: 9 January 2019
Ethics approval and consent to participate
: The study was approved by the Human Institutional Ethics Committee Mizan-Tepi University, and a written informed consent was obtained from all participants.All authors have approved the final draft.
: The participants provided informed consent to publish.
: All the authors declare that they have no competing interests and no conflict of interest.
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