Received: 14 February 2018
Accepted: 23 May 2018
First Online: 31 May 2018
Ethics approval and consent to participate
: Ethics approval for this study was not required since the data is secondary and is available in the public domain. More details regarding DHS data and ethical standards are available at: ExternalRef removed.
: No consent to publish was needed for this study as we did not use any details, images or videos related to individual participants. In addition data used is available in the public domain.
: The authors declare that they have no competing interests.
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