Funding for this research was provided by:
Camden Primary Care Trust
Text and Data Mining valid from 2018-09-10
Received: 19 January 2017
Accepted: 7 June 2018
First Online: 10 September 2018
Ethics approval and consent to participate
: The project was approved by the London School of Hygiene and Tropical Medicine Observational/Interventions Research Ethics Committee, reference number 6356. Written consent was obtained from all participants.
: Not applicable.
: The authors declare they have no competing interests.
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