Funding for this research was provided by:
Text and Data Mining valid from 2019-12-01
Received: 10 March 2019
Accepted: 15 November 2019
First Online: 12 December 2019
Ethics approval and consent to participate
: For the trend analysis, we used anonymised, aggregate and publicly available routine data, which did not require ethical approval. The Usher Research Ethics Committee, University of Edinburgh approved the expert consultation (No: 1862). Participants in the transparent expert consultation gave written informed consent to participate.
: Not applicable.
: One of the authors (AMF) is a member of the Editorial Board of this journal; but had no role in the editorial process for this manuscript. R. M is Head of Policy and Public Affairs for Marie Curie Scotland. The authors declare that they have no other competing interests.