FHIR Release 3 (STU) 4

This page is part of the FHIR Specification (v3.0.2: (v4.0.1: R4 - Mixed Normative and STU 3). ) in it's permanent home (it will always be available at this URL). 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 R3 R4 R3

Extension-codesystem-usage.json

Vocabulary Work Group Maturity Level : N/A Ballot Standards Status : Informative

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

usage

{
  "resourceType": "StructureDefinition",
  "id": "codesystem-usage",
  "extension": [

  "resourceType" : "StructureDefinition",
  "id" : "codesystem-usage",
  "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/codesystem-usage",
  "version" : "4.0.1",
  "name" : "usage",
  "status" : "draft",
  "date" : "2019-11-01T09:29:23+11:00",
  "publisher" : "HL7",
  "description" : "Consumers of the value set and the implementations, projects or standards that the author has utilized the value set in.",
  "fhirVersion" : "4.0.1",
  "mapping" : [{
    "identity" : "rim",
    "uri" : "http://hl7.org/v3",
    "name" : "RIM Mapping"
  }],
  "kind" : "complex-type",
  "abstract" : false,
  "context" : [{
    "type" : "element",
    "expression" : "CodeSystem"
  }],
  "type" : "Extension",
  "baseDefinition" : "http://hl7.org/fhir/StructureDefinition/Extension",
  "derivation" : "constraint",
  "snapshot" : {
    "element" : [{
      "id" : "Extension",
      "path" : "Extension",
      "short" : "Who has used and how?",
      "definition" : "Consumers of the value set and the implementations, projects or standards that the author has utilized the value set in.",
      "comment" : "This is likely to be a ???point in time??? view and should not be considered an authoritative listing of all uses of the value set.",
      "min" : 0,
      "max" : "*",
      "base" : {
        "path" : "Extension",
        "min" : 0,
        "max" : "*"
      },
      "condition" : ["ele-1"],
      "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" : "http://hl7.org/fhir/StructureDefinition/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
    },

    {
      "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
      "valueCode": "vocab"

      "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",
          "valueUrl" : "string"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]

    },
    {
      "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
      "valueInteger": 1
    }
  ],
  "url": "http://hl7.org/fhir/StructureDefinition/codesystem-usage",
  "name": "usage",
  "status": "draft",
  "date": "2019-10-24T11:53:00+11:00",
  "publisher": "HL7",
  "description": "Consumers of the value set and the implementations, projects or standards that the author has utilized the value set in.",
  "fhirVersion": "3.0.2",
  "mapping": [

      "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" : "http://hl7.org/fhir/StructureDefinition/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,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]
    },

    {
      "identity": "rim",
      "uri": "http://hl7.org/v3",
      "name": "RIM Mapping"
    }
  ],
  "kind": "complex-type",
  "abstract": false,
  "contextType": "resource",
  "context": [
    "CodeSystem"
  ],
  "type": "Extension",
  "baseDefinition": "http://hl7.org/fhir/StructureDefinition/Extension",
  "derivation": "constraint",
  "snapshot": {
    "element": [

      "id" : "Extension.extension:user",
      "path" : "Extension.extension",
      "sliceName" : "user",
      "short" : "A consumer of or client for the value set",
      "definition" : "This is most likely to be an organization but can be an individual. It would not be a program, that information should be recorded in the usage.use.",
      "min" : 1,
      "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" : "http://hl7.org/fhir/StructureDefinition/Element"
      },

      {
        "id": "Extension",
        "path": "Extension",
        "short": "Who has used and how?",
        "definition": "Consumers of the value set and the implementations, projects or standards that the author has utilized the value set in.",
        "comment": "This is likely to be a ???point in time??? view and should not be considered an authoritative listing of all uses of the value set.",
        "min": 0,
        "max": "*",
        "base": {
          "path": "Extension",
          "min": 0,
          "max": "*"
        },
        "condition": [
          "ele-1"
        ],
        "constraint": [
          {
            "key": "ele-1",
            "severity": "error",
            "human": "All FHIR elements must have a @value or children",
            "expression": "hasValue() | (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

        "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,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:user.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",
          "valueUrl" : "string"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]
    },
    {
      "id" : "Extension.extension:user.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" : "http://hl7.org/fhir/StructureDefinition/Element"

      },
      {
        "id": "Extension.id",
        "path": "Extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]

        "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,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:user.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" : "user",
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.extension:user.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](http://hl7.org/fhir/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" : "http://hl7.org/fhir/StructureDefinition/Element"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.extension:use",
      "path" : "Extension.extension",
      "sliceName" : "use",
      "short" : "Implementation/project/standard that uses value set",
      "definition" : "A descriptive name of the project or standard in which the value set is used.",
      "min" : 1,
      "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" : "http://hl7.org/fhir/StructureDefinition/Element"

      },
      {
        "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. 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.",
        "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"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]

        "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,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:use.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",
          "valueUrl" : "string"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "n/a"
      }]
    },
    {
      "id" : "Extension.extension:use.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" : "http://hl7.org/fhir/StructureDefinition/Element"

      },
      {
        "id": "Extension.extension:user",
        "path": "Extension.extension",
        "sliceName": "user",
        "short": "A consumer of or client for the value set",
        "definition": "This is most likely to be an organization but can be an individual. It would not be a program, that information should be recorded in the usage.use.",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false

        "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,
      "isSummary" : false
    },
    {
      "id" : "Extension.extension:use.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" : "use",
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    },
    {
      "id" : "Extension.extension:use.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](http://hl7.org/fhir/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" : "http://hl7.org/fhir/StructureDefinition/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",
          "valueUrl" : "uri"
        }],
        "code" : "http://hl7.org/fhirpath/System.String"
      }],
      "fixedUri" : "http://hl7.org/fhir/StructureDefinition/codesystem-usage",
      "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](http://hl7.org/fhir/extensibility.html) for a list).",
      "min" : 0,
      "max" : "0",
      "base" : {
        "path" : "Extension.value[x]",
        "min" : 0,
        "max" : "1"
      },
      "type" : [{
        "code" : "base64Binary"

      },
      {
        "id": "Extension.extension:user.id",
        "path": "Extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]

        "code" : "boolean"

      },
      {
        "id": "Extension.extension:user.extension",
        "path": "Extension.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. 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.",
        "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"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]

        "code" : "canonical"

      },
      {
        "id": "Extension.extension:user.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": "user",
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]

        "code" : "code"

      },
      {
        "id": "Extension.extension:user.valueString",
        "path": "Extension.extension.valueString",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "string"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]

        "code" : "date"

      },
      {
        "id": "Extension.extension:use",
        "path": "Extension.extension",
        "sliceName": "use",
        "short": "Implementation/project/standard that uses value set",
        "definition": "A descriptive name of the project or standard in which the value set is used.",
        "min": 1,
        "max": "1",
        "base": {
          "path": "Element.extension",
          "min": 0,
          "max": "*"
        },
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false

        "code" : "dateTime"

      },
      {
        "id": "Extension.extension:use.id",
        "path": "Extension.extension.id",
        "representation": [
          "xmlAttr"
        ],
        "short": "xml:id (or equivalent in JSON)",
        "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": [
          {
            "code": "string"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]

        "code" : "decimal"

      },
      {
        "id": "Extension.extension:use.extension",
        "path": "Extension.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. 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.",
        "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"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "n/a"
          }
        ]

        "code" : "id"

      },
      {
        "id": "Extension.extension:use.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": "use",
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]

        "code" : "instant"

      },
      {
        "id": "Extension.extension:use.valueString",
        "path": "Extension.extension.valueString",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).",
        "min": 0,
        "max": "1",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "string"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]

        "code" : "integer"

      },
      {
        "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": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "http://hl7.org/fhir/StructureDefinition/codesystem-usage",
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]

        "code" : "markdown"

      },
      {
        "id": "Extension.value[x]",
        "path": "Extension.value[x]",
        "short": "Value of extension",
        "definition": "Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).",
        "min": 0,
        "max": "0",
        "base": {
          "path": "Extension.value[x]",
          "min": 0,
          "max": "1"
        },
        "type": [
          {
            "code": "base64Binary"
          },
          {
            "code": "boolean"
          },
          {
            "code": "code"
          },
          {
            "code": "date"
          },
          {
            "code": "dateTime"
          },
          {
            "code": "decimal"
          },
          {
            "code": "id"
          },
          {
            "code": "instant"
          },
          {
            "code": "integer"
          },
          {
            "code": "markdown"
          },
          {
            "code": "oid"
          },
          {
            "code": "positiveInt"
          },
          {
            "code": "string"
          },
          {
            "code": "time"
          },
          {
            "code": "unsignedInt"
          },
          {
            "code": "uri"
          },
          {
            "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": "Meta"
          }
        ],
        "mapping": [
          {
            "identity": "rim",
            "map": "N/A"
          }
        ]
      }
    ]
  },
  "differential": {
    "element": [

        "code" : "oid"
      },

      {
        "id": "Extension",
        "path": "Extension",
        "short": "Who has used and how?",
        "definition": "Consumers of the value set and the implementations, projects or standards that the author has utilized the value set in.",
        "comment": "This is likely to be a ???point in time??? view and should not be considered an authoritative listing of all uses of the value set.",
        "min": 0,
        "max": "*",
        "isModifier": false

        "code" : "positiveInt"

      },
      {
        "id": "Extension.extension:user",
        "path": "Extension.extension",
        "sliceName": "user",
        "short": "A consumer of or client for the value set",
        "definition": "This is most likely to be an organization but can be an individual. It would not be a program, that information should be recorded in the usage.use.",
        "min": 1,
        "max": "1",
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false

        "code" : "string"

      },
      {
        "id": "Extension.extension:user.extension",
        "path": "Extension.extension.extension",
        "max": "0"

        "code" : "time"

      },
      {
        "id": "Extension.extension:user.url",
        "path": "Extension.extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "user"

        "code" : "unsignedInt"

      },
      {
        "id": "Extension.extension:user.valueString",
        "path": "Extension.extension.valueString",
        "type": [
          {
            "code": "string"
          }
        ]

        "code" : "uri"

      },
      {
        "id": "Extension.extension:use",
        "path": "Extension.extension",
        "sliceName": "use",
        "short": "Implementation/project/standard that uses value set",
        "definition": "A descriptive name of the project or standard in which the value set is used.",
        "min": 1,
        "max": "1",
        "type": [
          {
            "code": "Extension"
          }
        ],
        "isModifier": false

        "code" : "url"

      },
      {
        "id": "Extension.extension:use.extension",
        "path": "Extension.extension.extension",
        "max": "0"

        "code" : "uuid"

      },
      {
        "id": "Extension.extension:use.url",
        "path": "Extension.extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "use"

        "code" : "Address"

      },
      {
        "id": "Extension.extension:use.valueString",
        "path": "Extension.extension.valueString",
        "type": [
          {
            "code": "string"
          }
        ]

        "code" : "Age"

      },
      {
        "id": "Extension.url",
        "path": "Extension.url",
        "type": [
          {
            "code": "uri"
          }
        ],
        "fixedUri": "http://hl7.org/fhir/StructureDefinition/codesystem-usage"

        "code" : "Annotation"

      },
      {
        "id": "Extension.value[x]",
        "path": "Extension.value[x]",
        "min": 0,
        "max": "0"
      }
    ]

        "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" : "http://hl7.org/fhir/StructureDefinition/Element"
      }],
      "isModifier" : false,
      "isSummary" : false,
      "mapping" : [{
        "identity" : "rim",
        "map" : "N/A"
      }]
    }]
  },
  "differential" : {
    "element" : [{
      "id" : "Extension",
      "path" : "Extension",
      "short" : "Who has used and how?",
      "definition" : "Consumers of the value set and the implementations, projects or standards that the author has utilized the value set in.",
      "comment" : "This is likely to be a ???point in time??? view and should not be considered an authoritative listing of all uses of the value set.",
      "min" : 0,
      "max" : "*",
      "isModifier" : false
    },
    {
      "id" : "Extension.extension:user",
      "path" : "Extension.extension",
      "sliceName" : "user",
      "short" : "A consumer of or client for the value set",
      "definition" : "This is most likely to be an organization but can be an individual. It would not be a program, that information should be recorded in the usage.use.",
      "min" : 1,
      "max" : "1",
      "type" : [{
        "code" : "Extension"
      }],
      "isModifier" : false
    },
    {
      "id" : "Extension.extension:user.extension",
      "path" : "Extension.extension.extension",
      "max" : "0"
    },
    {
      "id" : "Extension.extension:user.url",
      "path" : "Extension.extension.url",
      "type" : [{
        "code" : "uri"
      }],
      "fixedUri" : "user"
    },
    {
      "id" : "Extension.extension:user.value[x]",
      "path" : "Extension.extension.value[x]",
      "min" : 1,
      "type" : [{
        "code" : "string"
      }]
    },
    {
      "id" : "Extension.extension:use",
      "path" : "Extension.extension",
      "sliceName" : "use",
      "short" : "Implementation/project/standard that uses value set",
      "definition" : "A descriptive name of the project or standard in which the value set is used.",
      "min" : 1,
      "max" : "1",
      "type" : [{
        "code" : "Extension"
      }],
      "isModifier" : false
    },
    {
      "id" : "Extension.extension:use.extension",
      "path" : "Extension.extension.extension",
      "max" : "0"
    },
    {
      "id" : "Extension.extension:use.url",
      "path" : "Extension.extension.url",
      "type" : [{
        "code" : "uri"
      }],
      "fixedUri" : "use"
    },
    {
      "id" : "Extension.extension:use.value[x]",
      "path" : "Extension.extension.value[x]",
      "min" : 1,
      "type" : [{
        "code" : "string"
      }]
    },
    {
      "id" : "Extension.url",
      "path" : "Extension.url",
      "fixedUri" : "http://hl7.org/fhir/StructureDefinition/codesystem-usage"
    },
    {
      "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.