Page History

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• Content relevant to an entire country may be relevant to include in a national extension, for example
  • Concepts used for reporting and quality metrics in a specific country or region
  • Representation of specific procedural concepts s uch such as a technique that is used nationally for testing purposes
  • Concepts that are mandated by government agencies that would otherwise be excluded from the International release by editorial policy
    
• Content relevant to a specific hospital may be included in a local extension, for example
  • Local interface terms or patient-friendly terms,  added added as extension descriptions which describe existing SNOMED CT concepts. 
  • Concepts representing specific hospital wards or beds
• Content relevant to a specific vendor may be included in a local extension, for example
  • System-specific interface terms or codes,  added added as extension descriptions which describe existing SNOMED CT concepts. 

As illustrated in

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• Create components
  • Principle and process for creating concepts:  5.4.2.1 Add Concept in an Extension
  • Principle and process for creating descriptions:  5.4.3.1 Add Description in an Extension
  • If you need to specify defining characteristics for concepts, for example following the creation of a new concept. See section  5.4.4.1 Add Relationship in an Extension for information about the principles and process for creating relationships 
  • See the  the Practical Guide to Reference Sets for more information about the different reference set types and their usage

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