Cancer Outcomes and Services Data set (COSD)

The Cancer Outcomes and Services Data set (COSD) is a compiled data set which provides the standard for secondary uses information required to support national cancer registration and associated analysis (at local, regional, national, and international level), as well as other national cancer audit programmes.

This standard consists of:

• a set of individual data items, with their definitions
• the assemblage of these data items into discrete data sets
• the means of flowing the data items
• compilation of the data items into a single reconciled and verified data set

All patients diagnosed with or receiving cancer treatment in or funded by the NHS in England are covered by the standard. This includes adult and paediatric cancer patients.

Providers of cancer services have been required to provide a monthly return on all cancer patients diagnosed from 1 January 2013 using this data set. Data are collated via the National Disease Registration Service (NDRS) local offices, and formal mechanisms for transmission of data from Providers to NDRS have been extended to carry COSD.

Why is COSD needed?

Periodically we needed to revise the COSD to ensure that we meet the current information requirements for the NHS. The Cancer Reform Strategy (2007) identified better information and stronger commissioning as 2 of the key drivers to achieve the goal that cancer services in this country should be amongst the best in the world.

The Achieving World-Class Cancer Outcomes, A Strategy for England 2015 to 2020 (Taskforce Report) further strengthens the need to have strong cancer data collection and empowers NHS England to enforce this through the mandate of data collection. These data will be the base for cancer analysis and research for the next 5 years.

What is included in the COSD data collection?

The COSD specifies the data items that need to be recorded for all cancer patients by the NHS in England. This includes all the items that Providers should submit electronically directly to the NDRS on a monthly basis.

These items can be submitted from different systems such as Cancer Management Information System software, PAS (Patient Administration Systems) and Pathology Laboratory Information Management Systems (LIMS).

Whilst some of these items are generic there are also a number of site-specific items which are required in order to record and analyse services and outcomes. These items are also required locally by service providers for patient management and clinical care.

This guide provides a description of the data items, the tumour sites or disease types to which they apply, and any further information needed to collect them.

Some items in the COSD are submitted through other standard NHS routes such as Cancer Waiting Times and do not need to be submitted directly for COSD (although some key items, such as treatment details, need to be submitted for both).

Data from all sources, whether direct Provider submissions from other national collections or derived from other sources, are linked by the NDRS at patient and tumour level using NHS Number to complete the full data set.

More information can be found in the Change Specification, Requirements Specification and Implementation Guidance on the NHS Digital website or supporting documentation can be found in the downloads and additional resources sections of this page.

COSD data collection during the COVID-19 pandemic

With the COVID-19 pandemic now affecting all aspects of NHS care, the following guidance has been drawn up to enable (Multi Disciplinary Team) MDT coordinators to record the new COVID related ICD10 codes into the existing COSD data set where applicable.

COSD Guidance for recording cancer data during the COVID-19 pandemic

This allows for all data on patients with a diagnosis of cancer and a COVID-19 diagnosis to be recorded in one record and reduce the burden of data collection within Trusts. In addition these new data items will aid in creating PTLs, so patients do not get lost in the system if treatment is delayed for any reason.

The National Disease Registration Service (NDRS) is delighted to announce the 2024 series of roadshows. These will explain the changes to the Cancer Outcomes and Services Data Set (COSD) and other key data set changes which effect the collection, quality assurance and reporting of Cancer Data.

The roadshows will be held around England at eight different locations and provide a networking opportunity for Cancer Services staff in NHS Trusts to meet other teams within their region.

You can find out more on the roadshow events page. 

What's new in COSD 2020

The new version of COSD v9.0 came into effect on the 1 April 2020. These changes continue to build on the work started in v7.0 and further rolled out through v8.1. They include some new amendments and re-alignments to the current data set, as well as a revision of the current schema specification in order to continue to meet the business objectives of the standard.

The COSD v9.0 amendments were made following extensive consultation over a 9 month period with 40 key groups or 150 clinical experts, including:

• site specific Expert Advisory Groups (EAGs) within PHE
• experts from within the National Cancer Registration and Analysis Service (NCRAS)
• clinical support and advice from the chair of the Royal College of Pathologists Working Group on Cancer Services
• cancer charities (Cancer Research UK, AMMF - The Cholangiocarcinoma Charity, Breast Cancer Care, Living Beyond Cancer and MacMillan)
• patient groups and individuals through ‘Use My Data’ and the EAGs
• national cancer audits
• cancer and pathology system suppliers
• NHS England
• Cancer Waiting Times (CWT)
• quality surveillance
• cancer taskforce transformation board

This revision allowed the data sets to be clinically reviewed, validated and updated by experts in all fields of cancer, and provides a clinically sound set of data to be collected from April 2020 onwards.

However, it was recognised that there were still further improvements required within this release to improve data quality and to be more reflective of current and future changes in cancer treatments, outcomes and clinical care.

Mandating key data items was vital in this release to improve data quality and reduce the burden of data processing within NCRAS. If a treatment record for example is submitted without a date or modality, it is of no use as a cancer registration event, however a registration officer would still have to review each incomplete record submitted, this multiplied by thousands of incomplete records per year was an unsustainable practice.

It also provides a clinically sound set of data which meets crucial recommendations in the Achieving World-Class Cancer Outcomes, A Strategy for England 2015-2020 (Cancer Taskforce Report).

Key changes to COSD

In total, 101 new data items (18 pathology specific) were added to meet the changing demands of cancer treatment and outcome data. In addition, there were 80 data items deleted, of which 12 are pathology specific. More importantly, this version has a strong emphasis on improving data quality and ascertainment along with formally separating pathology away from the patient pathway elements of a cancer record.

Many sections in the core now have mandatory elements within them, this will drive up data quality without creating undue burden on either the people collecting the data (within the Trusts) or those processing the data (within NCRAS).

In COSD v9.0 there has been an emphasis on improving data quality and ascertainment along with formally separating pathology away from the patient pathway elements of a cancer record. 

Other new features in v9.0 include:

• 101 new data items (18 pathology specific) to meet the changing demands of cancer treatment and outcome data, e.g. in relation to acute oncology, HPV testing for head and neck cancers
• deletion of 80 data items, of which 12 are pathology specific
• certain key data items are being made mandatory, to improve data quality and reduce the burden of data processing
• the addition of choices to data items to enable clearer decision making and improve data quality
• an update of the pathology data items to align with the Royal College of Pathologists’ ‘Core’ data sets
• new data items within the Breast and Upper GI site specific sections
• new data items to support the Living With and Beyond Cancer campaign
• an improved mechanism for recording all ‘Non Primary Cancer Pathway’ to improve collection and data quality
• realignment or movement of data items, to ensure that data nests correctly within the XML

Many data have been re-aligned across the data set into the correct higher level groupings. The data set maintains its ability to be interpreted within the following 2 subsets of data.

Pathology

This was part of the last standard and continues to be mandated across all Trusts to supply these data in COSD XML directly from their pathology departments.

It uses a different schema from COSD and has been formally separated within this version review and release.

Patient pathway

This is the data excluding Pathology, which the Cancer Services Teams need to collect. By formally removing the pathology data from their workload, this could reduce their burden of data collection by up to 30% across the whole data set.

As these data are now collected and submitted by the pathology departments directly, it is a huge burden of duplication if we ask the Cancer Services (non-clinical) teams to transcribe the same data into COSD via a Trust's Cancer Information System.

Wherever possible, duplication across the data set has now been removed and full explanations of how to collect these data within the new structure provided within the changelog of the data set.

Where there were data that are no longer part of a linked national data set (for example, Royal College of Pathologists), these have also been removed from the data set. Expert advice and guidance was provided by the Royal College of Pathologists during the review of the COSD Pathology v4.0 data set.

Collaboration between the (CWT) data set developers and COSD have improved both data sets by removing or enhancing specific shared data items.

The downloads and additional resources section of this page contain updated versions of the COSD, Guidance and supporting documentation for both the main COSD and the final pathology specific data set. It also includes links to download the schema packs to support structured XML submissions.

See the NHS Digital website for all other documentation, including the new Specification and Implementation guide.

The schedule below gives the deadline for providers to submit the COSD data for each calendar month of diagnosis/treatment. There is a later deadline for PAS feeds.

Feedback reports for the data submitted are available through the CancerStats2 website - (this opens in a new page)

Please note that this platform requires an N3/HSCN secure network connection. To ensure the best user experience, we encourage the use of modern web browsers such as Google Chrome, Mozilla Firefox or Microsoft Edge to access the platform. A small number of platform users have reported issues when opening reports using Internet Explorer.

We are here to help and value feedback and suggestions for how we can improve COSD. 

COSD helpdesk

If you have queries, requests for further information, comments and suggestions for newsletter content or possible new data to be considered for future COSD version changes please contact the COSD helpdesk at [email protected] 

The Data Liaison team within the National Disease Registration Service (NDRS) has a wealth of knowledge on cancer pathways and processes within NHS Trusts. NHS teams submitting data to NDRS can seek advice, support and find out more about the data improvement initiatives available to them directly from the regional Data Liaison Managers:

If you don't currently receive the newsletter and would like to be on the mailing list, please can you use this link to join the COSD newsletter mailing list, completing all the fields and ensure to select COSD Newsletter from the list. When the next newsletter is published you will then automatically be sent this.

View the latest COSD newsletter.

There are lots of resources available to support users with the implementation and collection of data as part of the COSD data set.

Here is a summary of the documents available:

Users can also refer to the NHS data model and dictionary developed for users involved in the collection of data and the management of information in the NHS.

To download either the main COSD or pathology schema packs, you first need to create a TRUD account.

How to create a TRUD account

Go straight to the NHS Digital TRUD website and:

• select 'create one now' (directly under 'log in')
• fill out the online form
• you will be sent a password
• log in with your new password - once logged in you can change your password via 'manage account' (top right hand of the screen)

How to download a schema pack

Once you have a TRUD account:

• go to the NHS Digital TRUD website and log in
• select 'DD XML Schemas' from the 'downloads' section (far left of the screen)
• identify the schema pack you want and 'subscribe to this data set'
• tick 'I accept the licence' and then 'request this subscription'
• you will receive a confirmation email
• download the required schema pack