1. Sickness absence data from 22 March 2020 to 2 January 2021, based on data from 137 acute NHS trusts, with East Suffolk and North Essex NHS Foundation Trust excluded due to data quality issues.
2. Figures for March and early April 2020 may be artificially low due to some trusts incorrectly submitting ‘0’ values, although further analysis removing these trusts suggests the first wave peak size is a reasonable estimate.
3. Employee numbers are based on headcount staff levels in September 2021 as opposed to the number of staff due to work on a given day.
Nuffield Trust analysis of NHS England and NHS Digital data.