Article History
Received: 22 March 2018
Accepted: 30 July 2018
First Online: 9 August 2018
Ethics approval and consent to participate
: The survey procedure and instruments used in the Demographic and Health Survey had already received ethical approval from the National Health Research Ethics Committee of the Federal Ministry of Health of Nigeria and the Ethics Committee of the Opinion Research Corporation Macro international, Inc. (ORC Macro Inc., Calverton, MD; USA). Permission to use the DHS data in the present study was obtained from The Demographic and Health Surveys (DHS) Program. The dataset does not contain any individual identifiers that would make it possible to track any participant.
: Not applicable
: The authors declare that they have no competing interests.
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