Received: 31 March 2020
Accepted: 22 December 2020
First Online: 12 January 2021
Ethics approval and consent to participate
: Data is not publicly available. According to the decision tool provided by the UK Health Research Authority (ExternalRef removed), this study was not considered to be research and did not require NHS Research Ethics Committee review. It therefore did not require ethical committee approval or informed consent. All data extracted from Laboratory Information and Management Systems were anonymised and local Trust processes were used to obtain approval for use of the data. In the case of University Hospitals of North Midlands NHS Trust, this was obtained from the Trust Pathology Directorate, and in the case of Salford Royal Hospital NHS Foundation Trust and Pennine Acute Hospitals Trust, this was obtained from the Northern Care Alliance NHS Group Trust Information Governance team.
: Not applicable.
: The authors declare that they have no competing interests.