Received: 6 January 2018
Accepted: 14 June 2018
First Online: 28 June 2018
Ethics approval and consent to participate
: Ethical approval was obtained from Health Research Ethics Committees of the University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu. Informed written consent was obtained from the participants.
: Not applicable
: The authors declare that they have no competing interests.
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