Funding for this research was provided by:
National Institute for Health Research (-)
National Institute for Health Research School for Primary Care Research
Oxford Biomedical Research Centre (-)
Oxford CLAHRC (-)
Received: 17 August 2018
Accepted: 9 July 2019
First Online: 3 August 2019
Ethics approval and consent to participate
: This systematic review and thematic analysis did not require ethics approval. We did not collect participant data for this study and, as such, did not require consent to participate.
: In this manuscript we present aggregated data from existing studies which had already been published.
: The authors declare that they have no competing interests.