Funding for this research was provided by:
Bill & Melinda Gates Foundation. (OPP1084472)
Received: 14 June 2018
Accepted: 14 November 2018
First Online: 26 November 2018
Ethics approval and consent to participate
: The study used secondary data, and hence there was no direct contact with the patients whose individual data was stripped of unique identifiers. Permission to use the data was obtained from the Zambia Ministry of Health and ethical clearance was obtained from the London School of Hygiene and Tropical Medicine (Ref 8410–01) and the University of Zambia Biomedical Research Ethics Committee (Ref 101–04-16).
: Not applicable
: The authors declare that they have no competing interests.
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