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Hospital Episode Statistics (HES)

Hospital Episode Statistics (HES) is a curated data product containing details about admissions, outpatient appointments and historical Accident and Emergency attendances at NHS hospitals in England.

About the HES data product

The HES data product is created from data submitted to NHS England as part of the Commissioning Data Set (CDS) which is managed by the Secondary Uses Service (SUS). At pre-arranged dates during a specific financial year, SUS takes a fixed snapshot of the CDS of cumulative activity recorded up to that point within that financial year.

This is then subject to additional processing to create a curated data product that is appended to finalised historical data that has been processed for previous years. Detail of the additional processing that occurs to create HES can be found on the Processing cycle and HES data quality page and the HES Technical Output Specification. HES has been designed to support ongoing business needs for many organisations with multiple user requirements.

Historically HES has been used for non-clinical purposes, such as research and planning health services. Because these uses are not related to direct patient care, they are called 'secondary uses'.

Improving how we use data to support the NHS was a key theme highlighted in the Data saves lives policy paper. HES data supports services like the NHS England Cohorting as a Service, and also research and innovation to power new medical treatments through services like the DigiTrials service. This is reflected in increased use of HES by customers for purposes relating to the direct care of individuals.

Through the increasing multiple use of HES the ongoing benefits provided by such a clearly defined data product is clear.

The Emergency Care Data Set (ECDS) is the national data set for urgent and emergency care, following a phased transition in reporting to the ECDS that commenced in October 2017. It replaced the HES Accident and Emergency Commissioning Data Set in April 2020.

HES does not include all mental health specific hospital activity, as Mental Health providers are required to submit this activity to the Mental Health Services Data Set (MHSDS).

Scope of the HES data

HES data covers all Sub Integrated Care Boards (Sub ICB) and Integrated Care Boards (ICB) in England (previously Clinical Commissioning Group, CCG), including:

  • private patients treated in NHS hospitals
  • patients resident outside of England
  • care delivered by treatment centres (including those in the independent sector) funded by the NHS

Each HES record contains a wide range of information about an individual patient admitted to an NHS hospital, including:

  • clinical information about diagnoses and operations
  • patient information, such as age group, gender and ethnicity
  • administrative information, such as dates and methods of admission and discharge
  • geographical information such as where patients are treated and the area where they live

Details of all the data fields that are present within HES with additional detail pertaining how they were derived or processed may be found within the HES Data Dictionary.

In providing a data product that supports the different requirements of its customers, HES also ensures that requirements of people described by the data are met through pseudonymisation, data minimisations and also through adherence to disclosure control rules around the reporting of aggregate outputs produced using the data. Further detail on these reporting rules may be found in the HES analysis guide.

The benefits of HES

HES can be used to:

  • monitor trends and patterns in NHS hospital activity
  • assess effective delivery of care
  • support local service planning
  • provide the basis for national indicators of clinical quality
  • reveal health trends over time
  • inform patient choice
  • determine fair access to health care
  • develop, monitor and evaluate government policy
  • support NHS and parliamentary accountability

HES publications

The HES data product is used to create a wide range of analytical and statistical outputs across many different organisations and teams. To support this activity NHS England produce the following monthly and annual official statistic reporting series which are available from the NHS England website.

Monthly HES publications

Monthly Accident and Emergency Quality Indicators

Annual HES publications for:

If you are interested in utilising HES data to support a specific need that may not be addressed through the content of our official statistics published outputs above then it is possible to apply for other standard and bespoke extracts using our Data Access Request Service.

Further information

internal Payment by Results

Payment by Results (PbR) is a system of paying NHS healthcare providers a standard national price or tariff for each patient seen or treated.

internal The processing cycle and HES data quality

Hospital Episode Statistics (HES) data comes from the routine submissions of data from providers to NHS Digital for the purposes of payment for and commissioning of healthcare in England.

internal Hospital Episode Statistics Data Dictionary

The Hospital Episode Statistics (HES) Data Dictionary is intended for use by all users of HES data. An NHS data dictionary works in the same way as a normal dictionary, but contains information about data items.

internal Hospital Episode Statistics data changes from 2021

From September 2021 we made changes to the way we process the Hospital Episode Statistics (HES) data set. These improvements provided data users with the tools to process larger volumes of data and manage incoming data to ensure that it is accurate, useful and secure.

internal Artificial data pilot

Artificial data sets provide users with large volumes of data that share some of the characteristics of real data while protecting patient confidentiality. They are designed to model the structure of real data but are completely artificial – they do not contain any actual patient records.

Last edited: 17 August 2023 2:06 pm