The SHMI is the ratio between the actual number of patients who die following hospitalisation at the trust and the number that would be expected to die on the basis of average England figures, given the characteristics of the patients treated there. It includes deaths which occurred in hospital and deaths which occurred outside of hospital within 30 days (inclusive) of discharge.
The SHMI gives an indication for each non-specialist acute NHS trust in England whether the observed number of deaths within 30 days of discharge from hospital was 'higher than expected' (SHMI banding=1), 'as expected' (SHMI banding=2) or 'lower than expected' (SHMI banding=3) when compared to the national baseline.
Trusts may be located at multiple sites and may be responsible for one or more hospitals. A breakdown of the data by site of treatment is also provided.
The SHMI is composed of 142 different diagnosis groups and these are aggregated to calculate the overall SHMI value for each trust. The number of finished provider spells, observed deaths and expected deaths at diagnosis group level for each trust is available in the SHMI diagnosis group breakdown files. For a subset of diagnosis groups, an indication of whether the observed number of deaths within 30 days of discharge from hospital was 'higher than expected', 'as expected' or 'lower than expected' when compared to the national baseline is also provided.
Details of the 142 diagnosis groups can be found in Appendix A of the SHMI specification.
1. There is a shortfall in the number of records for Tameside and Glossop Integrated Care NHS Foundation Trust (trust code RMP) meaning that values for this trust will be based on incomplete data and should therefore be interpreted with caution.
2. A large proportion of records for East Sussex Healthcare NHS Trust (trust code RXC) have missing information for the condition the patient was in hospital for and other conditions the patient suffers from, and this will have affected the calculation of the expected number of deaths. Values for this trust 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. There is also a shortfall in the number of records for this trust for April 2019. Values for this trust should therefore be interpreted with caution.
4. The following mergers took place on 1st October 2019: Cumbria Partnership NHS Foundation Trust (trust code RNN) merged with North Cumbria University Hospitals NHS Trust (trust code RNL). The new trust is called North Cumbria Integrated Care NHS Foundation Trust (trust code RNN). Aintree University Hospital NHS Foundation Trust (trust code REM) merged with Royal Liverpool and Broadgreen University Hospitals NHS Trust (trust code RQ6). The new trust is called Liverpool University Hospitals NHS Foundation Trust (trust code REM). However, as we received notification of these changes after data processing for this publication began, separate indicator values have been produced for this publication. The next publication in this series will reflect the updated 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.