Received: 16 April 2018
Accepted: 7 January 2019
First Online: 8 March 2019
Ethics approval and consent to participate
: Ethical clearance for the NDHS 2013 was obtained from the National Health Research Ethic Committee (NHREC) in Nigeria, before the survey was conducted [CitationRef removed]. In addition, permission to use the data was obtained from MEASURE DHS/ICF Macro International, the agency responsible for the worldwide Demographic and Health Surveys.
: Not applicable.
: The authors declare that they have no competing interests.
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