Release 5 Preview #1

This page is part of the FHIR Specification (v4.2.0: R5 Preview #1). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions . Page versions: R4B R4

Extension-valueset-expand-group.json

Vocabulary Work GroupMaturity Level: N/AStandards Status: Informative

Raw JSON (canonical form + also see JSON Format Specification)

expand-group

{
  "resourceType" : "StructureDefinition",
  "id" : "valueset-expand-group",
  "extension" : [{
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
    "valueCode" : "vocab"
  },
  {
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
    "valueInteger" : 1
  }],
  "url" : "http://hl7.org/fhir/StructureDefinition/valueset-expand-group",
  "version" : "4.2.0",
  "name" : "expand-group",
  "status" : "draft",
  "date" : "2019-12-31T21:03:40+11:00",
  "publisher" : "HL7",
  "description" : "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).",
  "fhirVersion" : "4.2.0",
  "mapping" : [{
    "identity" : "rim",
    "uri" : "http://hl7.org/v3",
    "name" : "RIM Mapping"
  }],
  "kind" : "complex-type",
  "abstract" : false,
  "context" : [{
    "type" : "element",
    "expression" : "ValueSet.compose.include"
  }],
  "type" : "Extension",
  "baseDefinition" : "http://hl7.org/fhir/StructureDefinition/Extension",
  "derivation" : "constraint",
  "snapshot" : {
    "element" : [{
      "id" : "Extension",
      "path" : "Extension",
      "short" : "Defines a hierarchy structure (when in UI mode)",
      "definition" : "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).",
      "comment" : "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.",
      "min" : 0,
      "max" : "*",
      "base" : {
        "path" : "Extension",
        "min" : 0,
        "max" : "*"
      },
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      },
      {
        "key" : "ext-1",
        "severity" : "error",
        "human" : "Must have either extensions or value[x], not both",
        "expression" : "extension.exists() != value.exists()",
        "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
        "source" : "http://hl7.org/fhir/StructureDefinition/Extension"
      }],
      "isModifier" : false
    },
    {
      "id" : "Extension.id",
      "path" : "Extension.id",
      "representation" : ["xmlAttr"],
      "short" : "Unique id for inter-element referencing",
      "definition" : "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
      "min" : 0,
      "max" : "1",
      "base" : {
        "path" : "Element.id",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
          "valueUri" : "string"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]
    },
    {
      "id" : "Extension.extension",
      "path" : "Extension.extension",
      "slicing" : {
        "discriminator" : [{
          "type" : "value",
          "path" : "url"
        }],
        "description" : "Extensions are always sliced by (at least) url",
        "rules" : "open"
      },
      "short" : "Additional content defined by implementations",
      "definition" : "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.",
      "comment" : "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.",
      "alias" : ["extensions",
      "user content"],
      "min" : 0,
      "max" : "*",
      "base" : {
        "path" : "Element.extension",
        "min" : 0,
        "max" : "*"
      },
      "type" : [{
        "code" : "Extension"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      },
      {
        "key" : "ext-1",
        "severity" : "error",
        "human" : "Must have either extensions or value[x], not both",
        "expression" : "extension.exists() != value.exists()",
        "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), \"value\")])",
        "source" : "Extension"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]
    },
    {
      "id" : "Extension.extension:code",
      "path" : "Extension.extension",
      "sliceName" : "code",
      "short" : "Underlying code from the system",
      "definition" : "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.",
      "comment" : "If there is no code, the group purely exists for display, and has no underlying meaning.",
      "min" : 0,
      "max" : "1",
      "base" : {
        "path" : "Element.extension",
        "min" : 0,
        "max" : "*"
      },
      "type" : [{
        "code" : "Extension"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      },
      {
        "key" : "ext-1",
        "severity" : "error",
        "human" : "Must have either extensions or value[x], not both",
        "expression" : "extension.exists() != value.exists()",
        "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), \"value\")])",
        "source" : "Extension"
      }],
      "isModifier" : false,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:code.id",
      "path" : "Extension.extension.id",
      "representation" : ["xmlAttr"],
      "short" : "Unique id for inter-element referencing",
      "definition" : "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
      "min" : 0,
      "max" : "1",
      "base" : {
        "path" : "Element.id",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
          "valueUri" : "string"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]
    },
    {
      "id" : "Extension.extension:code.extension",
      "path" : "Extension.extension.extension",
      "slicing" : {
        "discriminator" : [{
          "type" : "value",
          "path" : "url"
        }],
        "description" : "Extensions are always sliced by (at least) url",
        "rules" : "open"
      },
      "short" : "Extension",
      "definition" : "An Extension",
      "min" : 0,
      "max" : "0",
      "base" : {
        "path" : "Element.extension",
        "min" : 0,
        "max" : "*"
      },
      "type" : [{
        "code" : "Extension"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      },
      {
        "key" : "ext-1",
        "severity" : "error",
        "human" : "Must have either extensions or value[x], not both",
        "expression" : "extension.exists() != value.exists()",
        "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), \"value\")])",
        "source" : "Extension"
      }],
      "isModifier" : false,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:code.url",
      "path" : "Extension.extension.url",
      "representation" : ["xmlAttr"],
      "short" : "identifies the meaning of the extension",
      "definition" : "Source of the definition for the extension code - a logical name or a URL.",
      "comment" : "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.",
      "min" : 1,
      "max" : "1",
      "base" : {
        "path" : "Extension.url",
        "min" : 1,
        "max" : "1"
      },
      "type" : [{
        "code" : "uri"
      }],
      "fixedUri" : "code",
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.extension:code.value[x]",
      "path" : "Extension.extension.value[x]",
      "short" : "Value of extension",
      "definition" : "Value of extension - must be one of a constrained set of the data types (see [Extensibility](extensibility.html) for a list).",
      "min" : 1,
      "max" : "1",
      "base" : {
        "path" : "Extension.value[x]",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "code" : "code"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.extension:display",
      "path" : "Extension.extension",
      "sliceName" : "display",
      "short" : "Display for the group",
      "definition" : "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.",
      "min" : 0,
      "max" : "1",
      "base" : {
        "path" : "Element.extension",
        "min" : 0,
        "max" : "*"
      },
      "type" : [{
        "code" : "Extension"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      },
      {
        "key" : "ext-1",
        "severity" : "error",
        "human" : "Must have either extensions or value[x], not both",
        "expression" : "extension.exists() != value.exists()",
        "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), \"value\")])",
        "source" : "Extension"
      }],
      "isModifier" : false,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:display.id",
      "path" : "Extension.extension.id",
      "representation" : ["xmlAttr"],
      "short" : "Unique id for inter-element referencing",
      "definition" : "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
      "min" : 0,
      "max" : "1",
      "base" : {
        "path" : "Element.id",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
          "valueUri" : "string"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]
    },
    {
      "id" : "Extension.extension:display.extension",
      "path" : "Extension.extension.extension",
      "slicing" : {
        "discriminator" : [{
          "type" : "value",
          "path" : "url"
        }],
        "description" : "Extensions are always sliced by (at least) url",
        "rules" : "open"
      },
      "short" : "Extension",
      "definition" : "An Extension",
      "min" : 0,
      "max" : "0",
      "base" : {
        "path" : "Element.extension",
        "min" : 0,
        "max" : "*"
      },
      "type" : [{
        "code" : "Extension"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      },
      {
        "key" : "ext-1",
        "severity" : "error",
        "human" : "Must have either extensions or value[x], not both",
        "expression" : "extension.exists() != value.exists()",
        "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), \"value\")])",
        "source" : "Extension"
      }],
      "isModifier" : false,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:display.url",
      "path" : "Extension.extension.url",
      "representation" : ["xmlAttr"],
      "short" : "identifies the meaning of the extension",
      "definition" : "Source of the definition for the extension code - a logical name or a URL.",
      "comment" : "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.",
      "min" : 1,
      "max" : "1",
      "base" : {
        "path" : "Extension.url",
        "min" : 1,
        "max" : "1"
      },
      "type" : [{
        "code" : "uri"
      }],
      "fixedUri" : "display",
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.extension:display.value[x]",
      "path" : "Extension.extension.value[x]",
      "short" : "Value of extension",
      "definition" : "Value of extension - must be one of a constrained set of the data types (see [Extensibility](extensibility.html) for a list).",
      "min" : 1,
      "max" : "1",
      "base" : {
        "path" : "Extension.value[x]",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "code" : "string"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.extension:member",
      "path" : "Extension.extension",
      "sliceName" : "member",
      "short" : "Codes or other groups in this group",
      "definition" : "One of more codes that identify codes in the expansion or other groups.",
      "comment" : "A group without a code can be included by giving it an id and using #[id] in place of the code.",
      "min" : 1,
      "max" : "*",
      "base" : {
        "path" : "Element.extension",
        "min" : 0,
        "max" : "*"
      },
      "type" : [{
        "code" : "Extension"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      },
      {
        "key" : "ext-1",
        "severity" : "error",
        "human" : "Must have either extensions or value[x], not both",
        "expression" : "extension.exists() != value.exists()",
        "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), \"value\")])",
        "source" : "Extension"
      }],
      "isModifier" : false,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:member.id",
      "path" : "Extension.extension.id",
      "representation" : ["xmlAttr"],
      "short" : "Unique id for inter-element referencing",
      "definition" : "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
      "min" : 0,
      "max" : "1",
      "base" : {
        "path" : "Element.id",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
          "valueUri" : "string"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]
    },
    {
      "id" : "Extension.extension:member.extension",
      "path" : "Extension.extension.extension",
      "slicing" : {
        "discriminator" : [{
          "type" : "value",
          "path" : "url"
        }],
        "description" : "Extensions are always sliced by (at least) url",
        "rules" : "open"
      },
      "short" : "Extension",
      "definition" : "An Extension",
      "min" : 0,
      "max" : "0",
      "base" : {
        "path" : "Element.extension",
        "min" : 0,
        "max" : "*"
      },
      "type" : [{
        "code" : "Extension"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      },
      {
        "key" : "ext-1",
        "severity" : "error",
        "human" : "Must have either extensions or value[x], not both",
        "expression" : "extension.exists() != value.exists()",
        "xpath" : "exists(f:extension)!=exists(f:*[starts-with(local-name(.), \"value\")])",
        "source" : "Extension"
      }],
      "isModifier" : false,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:member.url",
      "path" : "Extension.extension.url",
      "representation" : ["xmlAttr"],
      "short" : "identifies the meaning of the extension",
      "definition" : "Source of the definition for the extension code - a logical name or a URL.",
      "comment" : "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.",
      "min" : 1,
      "max" : "1",
      "base" : {
        "path" : "Extension.url",
        "min" : 1,
        "max" : "1"
      },
      "type" : [{
        "code" : "uri"
      }],
      "fixedUri" : "member",
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.extension:member.value[x]",
      "path" : "Extension.extension.value[x]",
      "short" : "Value of extension",
      "definition" : "Value of extension - must be one of a constrained set of the data types (see [Extensibility](extensibility.html) for a list).",
      "min" : 1,
      "max" : "1",
      "base" : {
        "path" : "Extension.value[x]",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "code" : "code"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.url",
      "path" : "Extension.url",
      "representation" : ["xmlAttr"],
      "short" : "identifies the meaning of the extension",
      "definition" : "Source of the definition for the extension code - a logical name or a URL.",
      "comment" : "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.",
      "min" : 1,
      "max" : "1",
      "base" : {
        "path" : "Extension.url",
        "min" : 1,
        "max" : "1"
      },
      "type" : [{
        "extension" : [{
          "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
          "valueUri" : "uri"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "fixedUri" : "http://hl7.org/fhir/StructureDefinition/valueset-expand-group",
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.value[x]",
      "path" : "Extension.value[x]",
      "short" : "Value of extension",
      "definition" : "Value of extension - must be one of a constrained set of the data types (see [Extensibility](extensibility.html) for a list).",
      "min" : 0,
      "max" : "0",
      "base" : {
        "path" : "Extension.value[x]",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "code" : "base64Binary"
      },
      {
        "code" : "boolean"
      },
      {
        "code" : "canonical"
      },
      {
        "code" : "code"
      },
      {
        "code" : "date"
      },
      {
        "code" : "dateTime"
      },
      {
        "code" : "decimal"
      },
      {
        "code" : "id"
      },
      {
        "code" : "instant"
      },
      {
        "code" : "integer"
      },
      {
        "code" : "integer64"
      },
      {
        "code" : "markdown"
      },
      {
        "code" : "oid"
      },
      {
        "code" : "positiveInt"
      },
      {
        "code" : "string"
      },
      {
        "code" : "time"
      },
      {
        "code" : "unsignedInt"
      },
      {
        "code" : "uri"
      },
      {
        "code" : "url"
      },
      {
        "code" : "uuid"
      },
      {
        "code" : "Address"
      },
      {
        "code" : "Age"
      },
      {
        "code" : "Annotation"
      },
      {
        "code" : "Attachment"
      },
      {
        "code" : "CodeableConcept"
      },
      {
        "code" : "Coding"
      },
      {
        "code" : "ContactPoint"
      },
      {
        "code" : "Count"
      },
      {
        "code" : "Distance"
      },
      {
        "code" : "Duration"
      },
      {
        "code" : "HumanName"
      },
      {
        "code" : "Identifier"
      },
      {
        "code" : "Money"
      },
      {
        "code" : "Period"
      },
      {
        "code" : "Quantity"
      },
      {
        "code" : "Range"
      },
      {
        "code" : "Ratio"
      },
      {
        "code" : "Reference"
      },
      {
        "code" : "SampledData"
      },
      {
        "code" : "Signature"
      },
      {
        "code" : "Timing"
      },
      {
        "code" : "ContactDetail"
      },
      {
        "code" : "Contributor"
      },
      {
        "code" : "DataRequirement"
      },
      {
        "code" : "Expression"
      },
      {
        "code" : "ParameterDefinition"
      },
      {
        "code" : "RelatedArtifact"
      },
      {
        "code" : "TriggerDefinition"
      },
      {
        "code" : "UsageContext"
      },
      {
        "code" : "Dosage"
      },
      {
        "code" : "Meta"
      }],
      "constraint" : [{
        "key" : "ele-1",
        "severity" : "error",
        "human" : "All FHIR elements must have a @value or children",
        "expression" : "hasValue() or (children().count() > id.count())",
        "xpath" : "@value|f:*|h:div",
        "source" : "Element"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    }]
  },
  "differential" : {
    "element" : [{
      "id" : "Extension",
      "path" : "Extension",
      "short" : "Defines a hierarchy structure (when in UI mode)",
      "definition" : "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).",
      "comment" : "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.",
      "min" : 0,
      "max" : "*",
      "isModifier" : false
    },
    {
      "id" : "Extension.extension:code",
      "path" : "Extension.extension",
      "sliceName" : "code",
      "short" : "Underlying code from the system",
      "definition" : "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.",
      "comment" : "If there is no code, the group purely exists for display, and has no underlying meaning.",
      "min" : 0,
      "max" : "1",
      "type" : [{
        "code" : "Extension"
      }]
    },
    {
      "id" : "Extension.extension:code.extension",
      "path" : "Extension.extension.extension",
      "max" : "0"
    },
    {
      "id" : "Extension.extension:code.url",
      "path" : "Extension.extension.url",
      "type" : [{
        "code" : "uri"
      }],
      "fixedUri" : "code"
    },
    {
      "id" : "Extension.extension:code.value[x]",
      "path" : "Extension.extension.value[x]",
      "min" : 1,
      "type" : [{
        "code" : "code"
      }]
    },
    {
      "id" : "Extension.extension:display",
      "path" : "Extension.extension",
      "sliceName" : "display",
      "short" : "Display for the group",
      "definition" : "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.",
      "min" : 0,
      "max" : "1",
      "type" : [{
        "code" : "Extension"
      }]
    },
    {
      "id" : "Extension.extension:display.extension",
      "path" : "Extension.extension.extension",
      "max" : "0"
    },
    {
      "id" : "Extension.extension:display.url",
      "path" : "Extension.extension.url",
      "type" : [{
        "code" : "uri"
      }],
      "fixedUri" : "display"
    },
    {
      "id" : "Extension.extension:display.value[x]",
      "path" : "Extension.extension.value[x]",
      "min" : 1,
      "type" : [{
        "code" : "string"
      }]
    },
    {
      "id" : "Extension.extension:member",
      "path" : "Extension.extension",
      "sliceName" : "member",
      "short" : "Codes or other groups in this group",
      "definition" : "One of more codes that identify codes in the expansion or other groups.",
      "comment" : "A group without a code can be included by giving it an id and using #[id] in place of the code.",
      "min" : 1,
      "max" : "*",
      "type" : [{
        "code" : "Extension"
      }]
    },
    {
      "id" : "Extension.extension:member.extension",
      "path" : "Extension.extension.extension",
      "max" : "0"
    },
    {
      "id" : "Extension.extension:member.url",
      "path" : "Extension.extension.url",
      "type" : [{
        "code" : "uri"
      }],
      "fixedUri" : "member"
    },
    {
      "id" : "Extension.extension:member.value[x]",
      "path" : "Extension.extension.value[x]",
      "min" : 1,
      "type" : [{
        "code" : "code"
      }]
    },
    {
      "id" : "Extension.url",
      "path" : "Extension.url",
      "fixedUri" : "http://hl7.org/fhir/StructureDefinition/valueset-expand-group"
    },
    {
      "id" : "Extension.value[x]",
      "path" : "Extension.value[x]",
      "min" : 0,
      "max" : "0"
    }]
  }
}

Usage note: every effort has been made to ensure that the examples are correct and useful, but they are not a normative part of the specification.