CDS UNIQUE IDENTIFIER

CDS UNIQUE IDENTIFIER  is the same as attribute RECORD IDENTIFIER.

CDS UNIQUE IDENTIFIER  provides a unique identity for the life-time of an episode carried in a Commissioning Data Set message.

Note that the CDS UNIQUE IDENTIFIER must be constructed without the use of PATIENT Confidential Information. This includes PATIENT Identifiers such as NHS NUMBER or LOCAL PATIENT IDENTIFIER (EXTENDED), as well as any text which may identify the PATIENT DIAGNOSIS of the PATIENT or any PATIENT procedures being undertaken.

See the Commissioning Data Set Submission Protocol for detailed information.

Once assigned, a Commissioning Data Set record must retain its CDS UNIQUE IDENTIFIER otherwise duplicate Commissioning Data Set records may be generated and stored in the Secondary Uses Service database.

The CDS UNIQUE IDENTIFIER has three components. The recommended constructs are given below.

For All CDS Types EXCEPT the EAL CDS Types:

For EAL End Of Period (EOP) CDS Types only (CDS 6-2 only):

For EAL Event During Period (EDP) CDS Types only (CDS 6-2 only):

Usage: CDS UNIQUE IDENTIFIER  is a mandatory data item when the Net Change Update Mechanism is used.  It is strongly advised that users of the Bulk Replacement Mechanism maintain a correctly generated CDS UNIQUE IDENTIFIER within the Commissioning Data Set data. This will establish a migration path towards the use of the Net Change Mechanism and will also then minimise the risk of creating duplicate Commissioning Data Set data in the Secondary Uses Service database.

• Note that senders of Commissioning Data Set data remain directly responsible for the integrity of the CDS UNIQUE IDENTIFIER

• It is a mandatory requirement for all submissions using the Net Change Update Mechanism that these two components are constructed correctly to ensure uniqueness of CDS UNIQUE IDENTIFIERS across the NHS. 

• The structure of 3b and 3c allows the EAL End of Period Census and the EAL Event During Period Census for the same EAL Entry to be linked (CDS 6-2 only).

There are circumstances in patient care application systems where the control of the UID key integrity may be suspect. These issues include:

a) Episode deletion (not resulting in a Commissioning Data Set deletion of previously submitted data sent to the original Commissioner); b) Episode re-sequencing (not resulting in a corresponding Commissioning Data Set records being sent); c) Service agreement alterations not resulting in correct adjustments - Old Service Agreement deletion / New Service Agreement addition d) Re-admissions causing duplicate keys on the Secondary Uses Service database.

Each use of an NHS ORGANISATION CODE within a Commissioning Data Set message must be associated with the release version of the NHS Organisation Code scheme. At present this may be derived locally by NHS IT systems.

The following values have been informally used in many Commissioning Data Set implementations and are recommended to be used:

* The values of A and B must be used in the formatting of the CDS UNIQUE IDENTIFIER.

Note: the Format/Length has been updated in Data Dictionary Change Notice 1808 "Correction of Format/Length Data Elements". The Data Set specifications that contain this item will be updated in the next version of the Information Standard where it is not already correct.