Funding for this research was provided by:
Health Technology Assessment Programme (11/129/61)
Received: 29 December 2017
Accepted: 6 June 2018
First Online: 27 June 2018
Ethics approval and consent to participate
: The study was approved by London Bridge Research Ethics Committee on 7 March 2013 (Reference 13/LO/0197). The senior GP at each participating general practice gave written informed consent to the participation of the practice population.
: Not applicable
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