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.
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 a new contextual indicator 'Percentage of provider spells with COVID-19 coding' which is part of this publication.
2. There is a shortfall in the number of records for Tameside and Glossop Integrated Care NHS Foundation Trust (trust code RMP) and University Hospital Southampton NHS Foundation Trust (trust code RHM). Values for these trusts are based on incomplete data and should therefore be interpreted with caution.
3. Day cases are excluded from the SHMI. However, some day cases for University College London Hospitals NHS Foundation Trust (trust code RRV) have been incorrectly classified as ordinary admissions meaning that they have been included in the SHMI. Values for this trust should therefore be interpreted with caution.
4. The following mergers took place on 1st April 2020: Taunton and Somerset NHS Foundation Trust (trust code RBA) merged with Somerset Partnership NHS Foundation Trust (trust code RH5). The new trust is called Somerset NHS Foundation Trust (trust code RH5). Luton and Dunstable University Hospital NHS Foundation Trust (trust code RC9) merged with Bedford Hospital NHS Trust (trust code RC1). The new trust is called Bedfordshire Hospitals NHS Foundation Trust (trust code RC9). Weston Area Health NHS Trust (trust code RA3) merged with University Hospitals Bristol NHS Foundation Trust (trust code RA7). The new trust is called University Hospitals Bristol and Weston NHS Foundation Trust (trust code RA7). Mid Essex Hospital Services NHS Trust (trust code RQ8) merged with Southend University Hospital NHS Foundation Trust (trust code RAJ) and Basildon and Thurrock University Hospitals NHS Foundation Trust (trust code RDD). The new trust is called Mid and South Essex NHS Foundation Trust (trust code RAJ). Please note that separate indicator values have been produced for these organisations for this publication. From the August 2020 publication onwards, we will reflect these new organisation structures.
5. 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.