Funding for this research was provided by:
National Institute of Health Research (ICA-SCL-2015-01-001)
Received: 28 October 2020
Accepted: 14 January 2021
First Online: 12 February 2021
Ethics approval and consent to participate
: The study used anonymous national datasets. ONS Individual Approvals for full data access were held by LP, UD and AP. CJE and WG accessed the aggregated data. Ethical approval was not required.
: Not applicable.
: We declare no competing interests.