Funding for this research was provided by:
Medical Research Council (MRC/ESRC Interdisciplinary 1+3 Studentship)
Text and Data Mining valid from 2018-12-01
Received: 21 December 2017
Accepted: 21 November 2018
First Online: 20 December 2018
Ethics approval and consent to participate
: The study received ethical approval from the London School of Hygiene and Tropical Medicine Ethics Committee, with application number 5922. Written informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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