The date when the value set version is no longer expected to be used to create new content. This is the first date-time when the value set version becomes Inactive, so this value MUST present on all Inactive value set versions. The start Date_time is expected to be as of 0001 UTC of the Expiration Date.

Upon reaching the Expiration Date, the value set Activity Status should be consdiered as inactive. An Inactive value set version may no longer be used to create new content, but it may be used to evaluate content created prior to the Expiration Date.

unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.

• unordered
• Open
• discriminators: value:url

Source of the definition for the extension code - a logical name or a URL.

The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).