Funding for this research was provided by:
Royal College of Surgeons of Edinburgh
Oxford-UCB Prize Fellowship
NIH Medical Scientist Training Program (T32GM007205)
NIHR Clinician Scientist Fellowship (NIHR/CS/2014/14/012)
Received: 15 November 2018
Accepted: 25 April 2019
First Online: 17 May 2019
Ethics approval and consent to participate
: Linkage of NHFD data was supported by the HQIP Data Access Request Group (DARG) and the Confidentiality Advisory Group (CAG) on behalf of the Secretary of State for Health and Social Care under s.251 NHS Act 2006 (CAG ref. 8–03(PR11)/2013). Access to HES APC was approved by the NHS Digital Independent Group Advising on the Release of Data (IGARD) and civil registration mortality data by the ONS Microdata Release Panel (MRP) under s.39(5) Statistics and Registration Service Act 2007. Formal research ethics committee approval was not required for secondary analysis of pseudonymised data in line with the NHS Health Research Authority Governance Arrangements for Research Ethics Committees (GAfREC) guidelines [CitationRef removed].
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.