Received: 30 May 2018
Accepted: 17 December 2018
First Online: 10 January 2019
Ethics approval and consent to participate
: Ethical approval to conduct the study and human subject research approval for this study was received from Jimma University, College of Natural Sciences, Research Ethics Committee and the medical director of the Hospital. As the study was retrospective, informed consent was not obtained from the study participants, but data were anonymous and kept confidential.
: Not applicable.
: The authors declare that they have no competing interests.
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