Funding for this research was provided by:
Research Trainees Coordinating Centre (PDF-2016-09-056)
NIHR Oxford Biomedical Research Centre (N/A)
Collaboration for Leadership in Applied Health Research and Care - Oxford (N/A)
Received: 29 February 2020
Accepted: 25 May 2020
First Online: 4 July 2020
Ethics approval and consent to participate
: Not applicable, systematic review.
: Not applicable.
: The authors declare that they have no competing interests.