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| Responsible Owner: Modeling and Methodology Work Group |
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Raw JSON ( canonical form + also see JSON Format Specification )
StructureDefinition for Extension
{
"resourceType": "StructureDefinition",
"id": "Extension",
"meta": {
"lastUpdated": "2019-10-24T11:53:00+11:00"
"resourceType" : "StructureDefinition",
"id" : "Extension",
"text" : {
"status" : "generated",
"div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\"><table border=\"0\" cellpadding=\"0\" cellspacing=\"0\" style=\"border: 0px #F0F0F0 solid; font-size: 11px; font-family: verdana; vertical-align: top;\"><tr style=\"border: 1px #F0F0F0 solid; font-size: 11px; font-family: verdana; vertical-align: top\"><th style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px\" class=\"hierarchy\"><a href=\"https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views\" title=\"The logical name of the element\">Name</a></th><th style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px\" class=\"hierarchy\"><a href=\"https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views\" title=\"Information about the use of the element\">Flags</a></th><th style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px\" class=\"hierarchy\"><a href=\"https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views\" title=\"Minimum and Maximum # of times the element can appear in the instance\">Card.</a></th><th style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px; width: 100px\" class=\"hierarchy\"><a href=\"https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views\" title=\"Reference to the type of the element\">Type</a></th><th style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px\" class=\"hierarchy\"><a href=\"https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views\" title=\"Additional information about the element\">Description & Constraints</a><span style=\"float: right\"><a href=\"https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views\" title=\"Legend for this format\"><img src=\"data:image/png;base64,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\" alt=\"doco\" style=\"background-color: inherit\"/></a></span></th></tr><tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white\"><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAyAAAAACCAYAAACg/LjIAAAAJUlEQVR4Xu3IIQEAAAgDsHd9/w4EQIOamFnaBgAA4MMKAACAKwNp30CqZFfFmwAAAABJRU5ErkJggg==)\" class=\"hierarchy\"><img src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAAWCAYAAAABxvaqAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3wYeFzIs1vtcMQAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAE0lEQVQI12P4//8/AxMDAwNdCABMPwMo2ctnoQAAAABJRU5ErkJggg==\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"data:image/png;base64,R0lGODlhEAAQAPQfAOvGUf7ztuvPMf/78/fkl/Pbg+u8Rvjqteu2Pf3zxPz36Pz0z+vTmPzurPvuw/npofbjquvNefHVduuyN+uuMu3Oafbgjfnqvf/3zv/3xevPi+vRjP/20/bmsP///wD/ACH5BAEKAB8ALAAAAAAQABAAAAVl4CeOZGme5qCqqDg8jyVJaz1876DsmAQAgqDgltspMEhMJoMZ4iy6I1AooFCIv+wKybziALVAoAEjYLwDgGIpJhMslgxaLR4/3rMAWoBp32V5exg8Shl1ckRUQVaMVkQ2kCstKCEAOw==\" alt=\".\" style=\"background-color: white; background-color: inherit\" title=\"Element\" class=\"hierarchy\"/> <a href=\"extensibility-definitions.html#Extension\" title=\"Extension : Optional Extension Element - found in all resources.\">Extension</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a style=\"padding-left: 3px; padding-right: 3px; border: 1px grey solid; font-weight: bold; color: black; background-color: #e6ffe6; padding-left: 3px; padding-right: 3px; border: 1px grey solid; font-weight: bold; color: black; background-color: #e6ffe6\" href=\"versions.html#std-process\" title=\"Standards Status = Normative\">N</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"types.html#Element\">Element</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\">Optional Extensions Element<br/><span style=\"font-style: italic\" title=\"ext-1\">+ Rule: Must have either extensions or value[x], not both</span><br/><br/>Elements defined in Ancestors: <a href=\"types.html#Element\" title=\"Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.\">id</a>, <a href=\"types.html#Element\" title=\"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 managable, 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.\">extension</a></td></tr>\r\n<tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: #F7F7F7\"><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAyAAAAACCAYAAACg/LjIAAAALUlEQVR4Xu3IoREAIAwEwfT6/ddA0GBAxO3NrLlKUj9263wAAAAvrgEAADClAVWFQIBRHMicAAAAAElFTkSuQmCC)\" class=\"hierarchy\"><img src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAAWCAYAAAABxvaqAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3wYeFzIs1vtcMQAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAE0lEQVQI12P4//8/AxMDAwNdCABMPwMo2ctnoQAAAABJRU5ErkJggg==\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAWCAYAAADJqhx8AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3wYeFzI3XJ6V3QAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAANklEQVQ4y+2RsQ0AIAzDav7/2VzQwoCY4iWbZSmo1QGoUgNMghvWaIejPQW/CrrNCylIwcOCDYfLNRcNer4SAAAAAElFTkSuQmCC\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAACXBIWXMAAAsTAAALEwEAmpwYAAAARklEQVQ4y2P8//8/AyWAhYFCMAgMuHjx4n+KXaCv+I0szW8WpCG8kFO1lGFKW/SIjAUYgxz/MzAwMDC+nqhDUTQyjuYFBgCNmhP4OvTRgwAAAABJRU5ErkJggg==\" alt=\".\" style=\"background-color: #F7F7F7; background-color: inherit\" title=\"Primitive Data Type\" class=\"hierarchy\"/> <a href=\"extensibility-definitions.html#Extension.url\" title=\"Extension.url : Source of the definition for the extension code - a logical name or a URL.\">url</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a style=\"padding-left: 3px; padding-right: 3px; color: black; null; padding-left: 3px; padding-right: 3px; color: black; null\" href=\"elementdefinition-definitions.html#ElementDefinition.isSummary\" title=\"This element is included in summaries\">Σ</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\">1..1</td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"datatypes.html#uri\">uri</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\">identifies the meaning of the extension<br/></td></tr>\r\n<tr style=\"border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white\"><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAyAAAAACCAYAAACg/LjIAAAAJUlEQVR4Xu3IIQEAAAgDsHd9/w4EQIOamFnaBgAA4MMKAACAKwNp30CqZFfFmwAAAABJRU5ErkJggg==)\" class=\"hierarchy\"><img src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAAWCAYAAAABxvaqAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3wYeFzIs1vtcMQAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAE0lEQVQI12P4//8/AxMDAwNdCABMPwMo2ctnoQAAAABJRU5ErkJggg==\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAWCAYAAADJqhx8AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3wYeFzME+lXFigAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAANklEQVQ4y+3OsRUAIAjEUOL+O8cJABttJM11/x1qZAGqRBEVcNIqdWj1efDqQbb3HwwwwEfABmQUHSPM9dtDAAAAAElFTkSuQmCC\" alt=\".\" style=\"background-color: inherit\" class=\"hierarchy\"/><img src=\"data:image/png;base64,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\" alt=\".\" style=\"background-color: white; background-color: inherit\" title=\"Data Type\" class=\"hierarchy\"/> <a href=\"extensibility-definitions.html#Extension.value_x_\" title=\"Extension.value[x] : Value of extension - must be one of a constrained set of the data types (see [Extensibility](extensibility.html) for a list).\">value[x]</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a style=\"padding-left: 3px; padding-right: 3px; color: black; null; padding-left: 3px; padding-right: 3px; color: black; null\" href=\"elementdefinition-definitions.html#ElementDefinition.isSummary\" title=\"This element is included in summaries\">Σ</a><a style=\"padding-left: 3px; padding-right: 3px; border: 1px maroon solid; font-weight: bold; color: #301212; background-color: #fdf4f4;; padding-left: 3px; padding-right: 3px; border: 1px maroon solid; font-weight: bold; color: #301212; background-color: #fdf4f4;\" href=\"conformance-rules.html#constraints\" title=\"This element has or is affected by some invariants\">C</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\">0..1</td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\"><a href=\"datatypes.html#open\">*</a></td><td style=\"vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px\" class=\"hierarchy\">Value of extension<br/></td></tr>\r\n<tr><td colspan=\"5\" class=\"hierarchy\"><br/><a href=\"https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views\" title=\"Legend for this format\"><img src=\"data:image/png;base64,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\" alt=\"doco\" style=\"background-color: inherit\"/> Documentation for this format</a></td></tr></table></div>"
},
"text": {
"status": "generated",
"div": "<div>!-- Snipped for Brevity --></div>"
"extension" : [{
"url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status",
"valueCode" : "normative"
},
"url": "http://hl7.org/fhir/StructureDefinition/Extension",
"name": "Extension",
"status": "draft",
"date": "2019-10-24T11:53:00+11:00",
"publisher": "HL7 FHIR Standard",
"contact": [
{
"url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-normative-version",
"valueCode" : "4.0.0"
},
{
"url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-type-characteristics",
"valueCode" : "can-bind"
},
{
"url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
"valueCode" : "fhir"
}],
"url" : "http://hl7.org/fhir/StructureDefinition/Extension",
"version" : "6.0.0-ballot3",
"name" : "Extension",
"status" : "active",
"experimental" : false,
"date" : "2025-11-27T16:48:47+00:00",
"publisher" : "HL7 International / FHIR Infrastructure",
"contact" : [{
"telecom" : [{
"system" : "url",
"value" : "http://hl7.org/fhir"
}]
},
{
"telecom" : [{
"system" : "url",
"value" : "http://www.hl7.org/Special/committees/fiwg"
}]
}],
"description" : "Extension Type: Optional Extension Element - found in all resources.",
"jurisdiction" : [{
"coding" : [{
"system" : "http://unstats.un.org/unsd/methods/m49/m49.htm",
"code" : "001",
"display" : "World"
}]
}],
"purpose" : "The ability to add extensions in a structured way is what keeps FHIR resources simple.",
"fhirVersion" : "6.0.0-ballot3",
"mapping" : [{
"identity" : "rim",
"uri" : "http://hl7.org/v3",
"name" : "RIM Mapping"
}],
"kind" : "complex-type",
"abstract" : false,
"type" : "Extension",
"baseDefinition" : "http://hl7.org/fhir/StructureDefinition/DataType",
"derivation" : "specialization",
"snapshot" : {
"element" : [{
"id" : "Extension",
"path" : "Extension",
"short" : "Optional Extensions Element",
"definition" : "Optional Extension Element - found in all resources.",
"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())",
"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()",
"source" : "http://hl7.org/fhir/StructureDefinition/Extension"
}],
"isModifier" : false,
"mapping" : [{
"identity" : "rim",
"map" : "n/a,N/A"
}]
},
{
"telecom": [
{
"system": "url",
"value": "http://hl7.org/fhir"
}
]
}
],
"description": "Base StructureDefinition for Extension Type",
"purpose": "The ability to add extensions in a structured way is what keeps FHIR resources simple.",
"fhirVersion": "3.0.2",
"mapping": [
"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"
}],
"condition" : ["ele-1"],
"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,
"type": "Extension",
"baseDefinition": "http://hl7.org/fhir/StructureDefinition/Element",
"derivation": "specialization",
"snapshot": {
"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. To make the use of extensions safe and managable, 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())",
"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"
}],
"isModifier" : false,
"isSummary" : true,
"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" : "1",
"base" : {
"path" : "Extension.value[x]",
"min" : 0,
"max" : "1"
},
"type" : [{
"code" : "base64Binary"
},
{
"id": "Extension",
"path": "Extension",
"short": "Optional Extensions Element",
"definition": "Optional Extension Element - found in all resources.",
"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')])"
}
],
"mapping": [
{
"identity": "rim",
"map": "n/a"
},
{
"identity": "rim",
"map": "N/A"
}
]
"code" : "boolean"
},
{
"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"
}
]
"code" : "canonical"
},
{
"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"
}
]
"code" : "code"
},
{
"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",
"type": [
{
"code": "uri"
}
],
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
"code" : "date"
},
{
"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": "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"
}
]
}
]
"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" : "CodeableReference"
},
{
"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" : "RatioRange"
},
{
"code" : "Reference"
},
{
"code" : "SampledData"
},
{
"code" : "Signature"
},
{
"code" : "Timing"
},
{
"code" : "ContactDetail"
},
{
"code" : "DataRequirement"
},
{
"code" : "Expression"
},
{
"code" : "ParameterDefinition"
},
{
"code" : "RelatedArtifact"
},
{
"code" : "TriggerDefinition"
},
{
"code" : "UsageContext"
},
{
"code" : "Availability"
},
{
"code" : "ExtendedContactDetail"
},
{
"code" : "VirtualServiceDetail"
},
{
"code" : "Dosage"
},
{
"code" : "Meta"
}],
"condition" : ["ext-1"],
"constraint" : [{
"key" : "ele-1",
"severity" : "error",
"human" : "All FHIR elements must have a @value or children",
"expression" : "hasValue() or (children().count() > id.count())",
"source" : "http://hl7.org/fhir/StructureDefinition/Element"
}],
"isModifier" : false,
"isSummary" : true,
"mapping" : [{
"identity" : "rim",
"map" : "N/A"
}]
}]
},
"differential": {
"element": [
"differential" : {
"element" : [{
"id" : "Extension",
"path" : "Extension",
"short" : "Optional Extensions Element",
"definition" : "Optional Extension Element - found in all resources.",
"min" : 0,
"max" : "*",
"constraint" : [{
"key" : "ext-1",
"severity" : "error",
"human" : "Must have either extensions or value[x], not both",
"expression" : "extension.exists() != value.exists()",
"source" : "http://hl7.org/fhir/StructureDefinition/Extension"
}],
"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",
"type" : [{
"extension" : [{
"url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl" : "uri"
}],
"code" : "http://hl7.org/fhirpath/System.String"
}],
"isSummary" : true,
"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" : "1",
"type" : [{
"code" : "base64Binary"
},
{
"id": "Extension",
"path": "Extension",
"short": "Optional Extensions Element",
"definition": "Optional Extension Element - found in all resources.",
"min": 0,
"max": "*",
"constraint": [
{
"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')])"
}
],
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
"code" : "boolean"
},
{
"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",
"type": [
{
"code": "uri"
}
],
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
"code" : "canonical"
},
{
"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": "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"
}
]
}
]
"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" : "CodeableReference"
},
{
"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" : "RatioRange"
},
{
"code" : "Reference"
},
{
"code" : "SampledData"
},
{
"code" : "Signature"
},
{
"code" : "Timing"
},
{
"code" : "ContactDetail"
},
{
"code" : "DataRequirement"
},
{
"code" : "Expression"
},
{
"code" : "ParameterDefinition"
},
{
"code" : "RelatedArtifact"
},
{
"code" : "TriggerDefinition"
},
{
"code" : "UsageContext"
},
{
"code" : "Availability"
},
{
"code" : "ExtendedContactDetail"
},
{
"code" : "VirtualServiceDetail"
},
{
"code" : "Dosage"
},
{
"code" : "Meta"
}],
"condition" : ["ext-1"],
"isSummary" : true,
"mapping" : [{
"identity" : "rim",
"map" : "N/A"
}]
}]
}
}
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.
FHIR
®©
HL7.org
2011+.
FHIR
Release
3
(STU;
v3.0.2-11200)
R6
hl7.fhir.core#6.0.0-ballot3
generated
on
Thurs,
Oct
24,
2019
11:53+1100.
QA
Page
Thu,
Nov
27,
2025
16:52+0000.
Links:
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