Article History
Received: 4 June 2018
Accepted: 3 October 2018
First Online: 16 October 2018
Ethics approval and consent to participate
: The research protocol complies with the WHO ethical and safety recommendations and the Nigeria National Health Research Ethics Committee guidelines. Ethical approval and consent were obtained by the National Population Commission and ICF International.
: Not Applicable
: The authors declare that they have no competing interests.
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