Text and Data Mining valid from 2019-04-03
Received: 16 January 2018
Accepted: 27 March 2019
First Online: 3 April 2019
Ethics approval and consent to participate
: Ethical approval was obtained from the Bowen University Teaching Hospital Research Ethics Committee with registration number NHREC/12/04/2012. Being a retrospective review, informed consent was not obtained from individual participants but approval to carry out the study was obtained from the institution Ethics Committee.
: Not applicable.
: The authors declare that they have no competing interests.
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