Click on a letter in the Class menu to display the list of Classes for that letter. To display the definition for a specific Class, click on the Class name.

Each Class name is in uppercase.  Where the name appears in text in Red, it indicates that it is a hyperlink and if clicked on will display the definition for that Class.

The following information is available on a Class:

• "Description" tab: a description of the Class
• 
  
• "Attributes" tab: the Attributes which are associated with that Class
  • The unique identifier of a Class may include one or more Attributes. These are known as KEY attributes and are therefore shown with 'K' before the Attribute name.
  • Attributes are sequenced with the key Attributes first.
• 
  
• "Relationships" tab: the relationships between Classes
  • Description:
    • The nature of the relationship is indicated by: 'must be' if the relationship is mandatory and 'may be' if the relationship is optional.
    • Where relationships from one Class to others are mutually exclusive, then 'or' appears at the beginning of the description between the second and subsequent exclusive relationships. Mutually exclusive relationships are shown on diagrams by a short straight line cutting across the relationship.
  • Keys:
    • The unique identifier of a Class may include one or more relationships to other Classes. These are indicated by 'K' before the relationship description.
    • Relationships are sequenced with the key relationships first.
• 
  
• "Where Used" tab: every item where the Class is used.

For further information on Version 3 of the NHS Data Model and Dictionary, see About Version 3.