Funding for this research was provided by:
Economic and Social Research Council (ES/J500021/1)
Text and Data Mining valid from 2018-02-26
Accepted: 21 February 2018
First Online: 26 February 2018
Compliance with ethical standards
: We declare that we have no conflicts of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and national research committee (NHS Health Research Authority) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study.