Our definitions, remit and deliverables

Summary

Find out more about the National Casemix Office (NCO), its context within the health service, casemix methodology and the development and design of HRGs.

The term casemix has a number of meanings, from the literal mix of cases (patients) seen by a consultant, hospital or region, to the way patient care and treatments are classified into groups. These groups provide a useful measure on which to make performance comparisons, to cost healthcare, or to fund it.
 
The NCO are commissioned to develop and maintain a set of casemix groupings, called Healthcare Resource Groups (HRG), which provide a clinically-endorsed view of acute healthcare activities undertaken within the English NHS. These groups are generated via the Casemix Grouper Software, and the most current iteration is known as HRG4+.

HRGs are designed by clinicians to represent clinical care, within the boundaries of available, nationally mandated, data. Clinical leads on Casemix Expert Working Groups (EWGs) are nominated representatives of the Royal Colleges and professional bodies within the UK, and are joined on EWGs by finance and informatics professionals to ensure the HRGs can be practically implemented within the current national structure. They not only represent specialist hospitals, but also providers undertaking less complex, more routine, care. EWG members are not reimbursed for the time or expertise they provide.

Given that the HRG structure is currently aligned with patient body-systems, for both surgical and medical activities, there are over 30 EWGs that input into the development of the HRG Casemix Classification. Future enhancements for the development of Community Health Groups will expand this number.

Clinical input and experience has allowed the current HRG4+ classification to acknowledge the additional resource use required when treating patients who:

  • have multiple complications and comorbidities that affect the clinical input for their care
  • require surgery at a very young age
  • require multiple procedures to be undertaken at the same time, within the same hospital admission or attendance
  • require surgery that utilises new devices, or innovation in traditional clinical approach
  • require more complex, rather than routine, care

To get an overview of the work of the NCO, we have produced a simple booklet which covers the basics. Download The Science of Casemix.

What is casemix?

The term casemix has a number of meanings, from the literal mix of cases (patients) seen by a consultant, hospital or region, to the way patient care and treatments are classified into groups. These groups provide a useful measure on which to make performance comparisons, to cost healthcare, or to fund it.
 
The NCO are commissioned to develop and maintain a set of casemix groupings, called Healthcare Resource Groups (HRG), which provide a clinically-endorsed view of acute healthcare activities undertaken within the English NHS. These groups are generated via the Casemix Grouper Software, and the most current iteration is known as HRG4+.

Clinical input and experience has allowed the current HRG4+ classification to acknowledge the additional resource use required when treating patients who:

  • have multiple complications and comorbidities that affect the clinical input for their care
  • require surgery at a very young age
  • require multiple procedures to be undertaken at the same time, within the same hospital admission or attendance
  • require surgery that utilises new devices, or innovation in traditional clinical approach
  • require more complex, rather than routine, care

Stakeholder engagement

The NCO are commissioned to create casemix currencies and the associated software to apply the design algorithms by NHS England. The HRGs provide a clinically-endorsed view of acute healthcare activities undertaken within the English NHS, which underpins both the National Reference Costs collection and the National Reimbursement System. The most current version is HRG4+. 

HRGs are designed by clinicians to represent clinical care, within the boundaries of available, nationally mandated, data. Clinical leads on Casemix Expert Working Groups (EWGs) are nominated representatives of the Royal Colleges and professional bodies within the UK, and are joined on EWGs by finance and informatics professionals to ensure the HRGs can be practically implemented within the current national structure. They not only represent specialist hospitals, but also providers undertaking less complex, more routine, care. EWG members are not reimbursed for the time or expertise they provide.

Given that the HRG structure is currently aligned with patient body-systems, for both surgical and medical activities, there are over 30 EWGs that input into the development of the HRG Casemix Classification. Future enhancements for the development of Community Health Groups will expand this number.

The NCO engages with more than 250 healthcare professionals via Expert Working Groups (EWGs) covering all clinical areas. The HRG designs are updated annually and represent clinical care, within the boundaries of available, nationally mandated data. 

Design framework

The Design Framework outlines the key principles that are essential to any casemix classification, and draws heavily from those utilised in the development of previous casemix classifications. The fundamentals are intended to assist EWG members in the assessment and interpretation of data and lay down the preferred strategic foundation and aims for the classification. 

Casemix analytics

We've produced HRG4+ 2014/15 reference cost appraisals for each subchapter, with the exception of UZ undefined groups. The appraisals are at subchapter-level, except where subchapters have an essential relationship, in which case the appraisal covers multiple subchapters, or in the case of paediatric medicine, is published at chapter level.

These appraisals have been endorsed by the Department of Health Reference Costs Team and use the published national and provider level reference costs from the 2014/15 collection to evaluate the performance of the HRGs in the HRG4+ 2014/15 reference costs design, focussing on the expected relativities between HRGs. They provide a basis from which to improve the data quality of the reference costs in future years, as well as providing an assessment of how well the HRG4+ casemix classification reflects current clinical practice and innovations in healthcare delivery.

Attention has been paid to areas where HRG performance has been significantly influenced by a small number of providers with atypical reported activity and/or costs. Tables also identity outlier costs, as submitted by individual providers.

Further appraisals and top-level performance summaries will be available in September 2018.