About the NHS Data Model and Dictionary Version 3

Following the issue of DSCN 07/2004 'Data Standards: Meta Model', the NHS Data Model and Dictionary was changed to reflect and be based upon a more generic logical data model which better supports the strategic way forward. This NHS Data Model and Dictionary was published as the NHS Data Model and Dictionary Version 3.

There was extensive quality assurance of Version 3 including involvement of the Data Definition Group. All Version 3 contents were cross mapped and checked to ensure consistency with the Version 2 contents. Version 3 superseded Version 2 on 1st May 2005.

Version 3 supports all the messages, data sets and central returns supported by Version 2 but the underlying structure was genericised. No changes were made to NHS Business Definitions.

Version 3 introduced a new Generic Model which is 'PERSON based' rather than 'ORGANISATION based'. The model has been developed around generic 'CARE ACTIVITY' for a PATIENT, with each event transaction being recorded. This has involved grouping many of the old classes into generic classes like ACTIVITY GROUP. However, none of the detail or approved definitions or value sets in Version 2 have been lost although some of the old class definitions will now be found in the new 'NHS Business Definitions'.

The NHS Data Dictionary Version 2 has been frozen and made available for archive information purposes only and has been watermarked accordingly. All changes to NHS information standards and the supporting Data Set Change Notices are now consistent only with Version 3.

Summary of main changes and enhancements incorporated within Version 3

The introduction of Version 3 had no impact on current information standards or system suppliers.

About the Generic Model

The Generic Model supports all the messages, data sets and central returns which the model supported but the underlying structure has been genericised. This involved grouping many of the old classes into generic classes like ACTIVITY GROUP. However, none of the detail was lost and most of the old class definitions can be found under 'NHS Business Definitions'. The number of diagrams has been greatly reduced and they now describe coherent areas of the model which is a far more useful approach for data modellers.

This has led to the creation of a new Generic Model which is 'PERSON based' rather than 'ORGANISATION based'. The model has been developed around generic 'CARE ACTIVITY' for a PATIENT, each event transaction being recorded.

The model is aimed at enabling all 'CARE ACTIVITIES' related to the same condition for the same PATIENT  to be recorded and linked across ORGANISATIONS. The different states of the same 'CARE ACTIVITY' are recorded as event transactions e.g. requested, intended, scheduled, provided, cancelled, etc. These different state events also drive the scheduling and capacity planning of resources (people, equipment, facilities, etc.) to deliver the care.

Although this may seem complicated, it is necessary both to form a coherent logical model and to relate physical information such as that which flows on the Data Sets to the logical model. Every physical item should be represented logically in the NHS Data Model and Dictionary. However, the scope of the logical model is greater than the physical information it holds and therefore not all logical information has a physical existence.

Contact us for more information: information.standards@hscic.gov.uk.