Announcement of methodological changes to the NHS Outcomes Framework emergency readmissions indicator

The emergency readmission indicators were last published in February 2021 using methodologies aligned across the NHS Outcomes Framework (NHSOF), Clinical Commissioning Group Outcomes Indicator Set (CCGOIS), and Compendium indicators. 

All of the indicators use Hospital Episode Statistics (HES) data as their primary data source and it is this data source that is undergoing a change in how it is derived, most significantly, in terms of how unique patients are identified.  More information about the nature of the changes and their impacts is available

This announcement describes how these changes will impact the results of these indicators from the next NHSOF publication onwards. Publications for Compendium and CCGOIS will also be impacted by this revised methodology.

From the March 2022 publication onwards, the methodology used within the NHSOF emergency readmissions indicator will include the changes described below. Full details of the updated methodology are available in the indicator specification document which is available to download.

The most significant change is that the unique identifier used to identify individuals has been updated to use the Master Person Service (MPS) Person_ID instead of the HES ID, which was previously used. The Person_ID is derived from a new standard person identifier algorithm that utilises insight from the MPS that confirms the individual’s identity using Patient Demographics Service (PDS) data on Spine. 

As identifying people across hospital admission and discharge activity is a key feature of these emergency readmission indicators this is where the most impact is expected to be seen. 

The impact of this change is very small. The following analysis is based on data for discharges in the period April 2013 to March 2019 for national and local breakdowns. Please note that the analysis is based on a comparison using “classic” HES data with one run using HESID and the other run using the new Person_ID. 

At a national level across all reporting years, the numerators show increases of up to 1,019 with an average increase of 750. The denominators all decrease, on average by 1,489 and with a maximum decrease of 1,966. On average, the indicator value increases by 0.015 or 0.11% of its value from 13.438 to 13.453. As expected, the year-on-year trends also match. 

At local authority level, the numerators show increases of up to 242 and decreases of 42. The denominators show increases of up to 57 and decreases of 994. Changes in the indicator values range from increases of up to 0.30 and decreases of 0.15. On average, the indicator values decrease by 0.003 from 13.244 using HESID and 13.241 using the Person_ID. As expected, the year-on-year trends also match.

The first publication to be affected by this change will be the March 2022 release, which covers discharges in the period April 2013 to March 2021. 

Questions and feedback on the publication are welcomed and should be sent to [email protected] or alternatively call 0300 303 5678.