Funding for this research was provided by:
National Institute for Health Research
Text and Data Mining valid from 2018-03-15
Received: 31 December 2016
Accepted: 7 March 2018
First Online: 15 March 2018
Ethics approval and consent to participate
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: Not applicable.
: SP is associate editor of BMC Health Service Research. HR works for Quit-51 who provided the data which were analysed in this work. Apart from this, the authors declare no competing interests.
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