This extension declares a group of concepts that is generated into the ValueSet.expansion.contains hierarchy when the expansion is generated for a UI. THere is no inherent assigned meaning to the hierarchy; it is used to help the user navigate the concepts. Each group has a display and/or a code, and a list of members, which are either concepts in the value set, or other groups (by code).

Note that there are inter-relationships between concept status/properties and the way the groups are built; these are described and documented in the (value set hierarchical example)[d.html]. Note that this extension should be ignored when the expansion is not generated for UI.

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. 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 can 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

A reference to a code from the include.system that defines the meaning associated with the group. Note that including the code in this extension does not include the code in the value set; if the code is intended to be in the value set, it must be listed directly as well.

If there is no code, the group purely exists for display, and has no underlying meaning.

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

An Extension

• 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 - must be one of a constrained set of the data types (see Extensibility for a list).

The description for the group (goes in ValueSet.expansion.contains.dispaly). All groups need a display; this can only be omitted if there is a code that can be used to determine the display.

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

An Extension

• 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 - must be one of a constrained set of the data types (see Extensibility for a list).

One of more codes that identify codes in the expansion or other groups.

A group without a code can be included by giving it an id and using #[id] in place of the code.

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

An Extension

• 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 - must be one of a constrained set of the data types (see Extensibility for a list).

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 - must be one of a constrained set of the data types (see Extensibility for a list).