Funding for this research was provided by:
Text and Data Mining valid from 2018-06-01
Received: 5 February 2018
Accepted: 22 May 2018
First Online: 1 June 2018
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: The DHS receive government permission and obtain informed consent from all participants. The Research Ethics Committee of the London School of Hygiene and Tropical Medicine approved our secondary analysis of anonymised data.
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: The authors declare that they have no competing interests.
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