Received: 3 October 2017
Accepted: 15 February 2018
First Online: 2 March 2018
Ethics approval and consent to participate
: This study was conducted according to the guidelines laid down in the Declaration of Helsinki and all procedures involving human subjects were approved by the Research and Ethics Committee of the EFSTH and the Research Review Committee of the School of Medicine and Allied Health Sciences, University of The Gambia. Written informed consent was obtained from all subjects.
: Not applicable.
: The authors declare that they have no competing interests.
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