Emergency care concepts to support users of the Emergency Care Data Set (ECDS) data product

Reporting of ECDS data (CDS type 011) started in October 2017 through a phased implementation by reporting organisations from the predecessor HES Accident and Emergency Commissioning Data Set (CDS type 010). This transition to reporting to ECDS was fully completed in April 2020. ECDS data coverage before April 2020 is not complete, although it available for use.

Data quality information regarding the coverage and completeness of the ECDS data product during this phased implementation is available through the processing cycle and ECDS data quality section to help inform its suitability for individual uses. 

HES A&E prior to April 2020 will continue to be available for use. Details of all the historical HES A&E data fields may be found in the Analytical HES TOS.

When a new CDS version is implemented or retired, new fields and values are introduced, and some existing fields and values are retired. Submitters of the data migrate to a new CDS version in a phased implementation, ensuing dual activity for both the versions during this time.

This has potential implications of the coverage and completeness of data fields specifically impacted by dataset version change which users should be mindful of when using the data product.

It is not automatically the case that availability of the new data items captured within a new data set version are incorporated into our analytical data products. A number of criteria must be met around business need and development cost and suitability from a governance perspective being met.

Users of the data product should consider the following scenarios when querying the data product during times of transition of dataset versions. For example, a new version of ECDS, V4 has been released for phased implementation in the financial year 2023/24 but as and when the new V4 data fields are made available they won't have universal coverage necessarily during this time. Alternatively, the coverage for existing fields in V3 that have retired in V4 will gradually decrease over the next year until all submitters have migrated to V4. Where possible we have sought to address this if an equivalent V4 field is being mapped back. This is stated in the Analytical ECDS Technical Output Specification (ATOS) where this is the case.

SNOMED CT codes are used in ECDS to record clinical information about patients. Concepts include: clinical findings, symptoms, diagnoses, procedures and many more.

Individual SNOMED CT codes are not included in the ATOS. Refer to the Enhanced Technical Output Specification (ETOS) for up-to-date valid ECDS SNOMED CT codes and definitions, for each field.

For the published data product, including DARS, cleaning is applied to all submitted SNOMED CT fields, against an approved list of valid values, to remove any invalid SNOMED CT values from this data product.

SNOMED CT terminology is constantly being reviewed, typically in response to specific requests for new functionality. This leads to new codes frequently being introduced and existing codes retired. More information on the update cycle is available on the Terminology Reference Update Distribution (TRUD) website. 

With the introduction of ECDS Diagnosis Max, having over 58,000 valid diagnosis codes, analysts need to consider these changes when tracking activity over time, as results may not be reflective for whole reported period.

Users can mitigate Diagnosis Max codes to the Core codes by using the mapping reference file, published by SUS: Secondary Uses Service what's new (November 2023, ECDS MAX parent child codes).

Streaming is low acuity, low complexity patients referred to other areas (dental, ophthalmology, pharmacy etc.). These are not a full emergency attendance with all fields populated and are not included in the predecessor HES A&E. If users wish to exclude these records, you can do so by excluding the ‘streamed’ values from the DISCHARGE_STATUS field available in the Enhanced Technical Output Specification (ETOS).

Derived fields are handled differently up to and including 2023/24 compared with 2024/25 onwards within the Data Platform Service (DPS) data product. This is to retain consistency with finalised published data for the earlier years, whilst applying improved, transparent derivations going forward.

For years up to 2023/24, derived fields will align with RDS SQL clones but may not align when the corporate reference data has changed mid-year. This is due to receiving ECDS as ‘delta’ feeds, whereby the derivations are applied only to the new or re-submitted ‘delta’ records, and do not re-visit the existing records.

From 2024/25 this has been rectified, whereby all derivations are refreshed collectively every day to align with the activity date of the patient’s ECDS attendance. This update only applies to the ECDS data product within the Data Platform Service (DPS), not the SQL RDS clones.

Details of each derivation is published in the Analytical Technical Output Specification.