These indicators are designed to accompany the SHMI publication.
As well as information on the main condition the patient is in hospital for (the primary diagnosis), the SHMI data contain up to 19 secondary diagnosis codes for other conditions the patient is suffering from. This information is used to calculate the expected number of deaths.
'Depth of coding' is defined as the number of secondary diagnosis codes for each record in the data. A higher mean depth of coding may indicate a higher proportion of patients with multiple conditions and/or comorbidities, but may also be due to differences in coding practices between trusts.
Contextual indicators on the mean depth of coding for elective and non-elective admissions are produced to support the interpretation of the SHMI.
Notes:
1. As of the July 2020 publication, COVID-19 activity has been excluded from the SHMI. The SHMI is not designed for this type of pandemic activity and the statistical modelling used to calculate the SHMI may not be as robust if such activity were included. Activity that is being coded as COVID-19, and therefore excluded, is monitored in the contextual indicator 'Percentage of provider spells with COVID-19 coding' which is part of this publication.
2. Please note that there was a fall in the overall number of spells from March 2020 due to COVID-19 impacting on activity for England and the number has not returned to pre-pandemic levels. Further information is available in the contextual indicator ‘Provider spells compared to the pre-pandemic period’ which is part of this publication.
3. There is a shortfall in the number of records for Ashford and St Peter's Hospitals NHS Foundation Trust (trust code RTK), County Durham and Darlington NHS Foundation Trust (trust code RXP), Frimley Health NHS Foundation Trust (trust code RDU), Mid Cheshire Hospitals NHS Foundation Trust (trust code RBT), North Bristol NHS Trust (trust code RVJ), Royal Surrey County Hospital NHS Foundation Trust (trust code RA2), and Wrightington, Wigan and Leigh NHS Foundation Trust (trust code RRF). Values for these trusts should therefore be interpreted with caution.
4. Further information on data quality can be found in the SHMI background quality report, which can be downloaded from the 'Resources' section of the publication page.