StructureDefinition
for
Reference
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(data: image/png;base64,iVBORw0KG
goAAAANSUhEUgAAAyAAAAACCAYAAACg/LjIAAAAL0lEQVR42u3XsQ0AQAgCQHdl/xn8jxvYWB3JlTR0VJLa+OltBwAAYP6EEQAAgC
sPVYVAgIJrA/sAAAAASUVORK5CYII=)
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAAWCAYAAAABxvaqAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB
3RJTUUH3wYeFzIs1vtcMQAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAE0lEQVQI12P4//8/AxMDAw
NdCABMPwMo2ctnoQAAAABJRU5ErkJggg==
data: image/png;base64,R0lGODlhEAAQAMQfAOvGUf7ztuvPMf/78/fkl/Pbg+u8Rvjqteu2Pf3zxPz36Pz0z+vTmPzurPvuw
/npofbjquvNefHVduuyN+uuMu3Oafbgjfnqvf/3zv/3xevPi+vRjP/20/bmsP///////yH5BAEAAB8ALAAAAAAQABAAAAV24CeOZG
mepqeqqOgxjBZFa+19r4ftWQUAgqDgltthMshMIJAZ4jYDHsBARSAmFOJvq+g6HIdEFgcYmBWNxoNAsDjGHgBnmV5bCoUDHLBIq9s
FEhIdcAYJdYASFRUQhQkLCwkOFwcdEBAXhVabE52ecDahKy0oIQA7
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4pxA reference from one resource to another
Elements defined in Ancestors:
unique id for the element within a resource (for internal references). This may be any
string value that does not contain spaces.,
May be used to represent additional information that is not part of the basic definition
of the element. In order to make the use of extensions safe and manageable, there is a
strict set of governance applied to the definition and use of extensions. Though any
implementer is allowed to define an extension, there is a set of requirements that SHALL
be met as part of the definition of the extension.
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(data: image/png;base64,iVBORw0KG
goAAAANSUhEUgAAAyAAAAACCAYAAACg/LjIAAAAL0lEQVR42u3XsQ0AQAgCQHdl/xn8jxvYWB3JlTR0VJLa+OltBwAAYP6EEQAAgC
sPVYVAgIJrA/sAAAAASUVORK5CYII=)
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAAWCAYAAAABxvaqAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB
3RJTUUH3wYeFzIs1vtcMQAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAE0lEQVQI12P4//8/AxMDAw
NdCABMPwMo2ctnoQAAAABJRU5ErkJggg==
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAWCAYAAADJqhx8AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB
3RJTUUH3wYeFzI3XJ6V3QAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAANklEQVQ4y+2RsQ0AIAzDav
7/2VzQwoCY4iWbZSmo1QGoUgNMghvWaIejPQW/CrrNCylIwcOCDYfLNRcNer4SAAAAAElFTkSuQmCC
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIW
XMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3gYBFzI0BrFQCwAAAERJREFUOMtj/P//PwMlgImBQjDwBrCcOnWKokBgYWBgYDCU+06W5i
8MUggvnH/EOVJjAW4AuQHJ+O75LYqikXE0LzAAALePEntTkEoSAAAAAElFTkSuQmCC
Reference.reference : A reference to a location at which the other resource is found.
The reference may be a relative reference, in which case it is relative to the service
base URL, or an absolute URL that resolves to the location where the resource is found.
The reference may be version specific or not. If the reference is not to a FHIR RESTful
server, then it should be assumed to be version specific. Internal fragment references
(start with '#') refer to contained resources.
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(data: image/png;base64,iVBORw0KG
goAAAANSUhEUgAAAyAAAAACCAYAAACg/LjIAAAAL0lEQVR42u3XsQ0AQAgCQHdl/xn8jxvYWB3JlTR0VJLa+OltBwAAYP6EEQAAgC
sPVYVAgIJrA/sAAAAASUVORK5CYII=)
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAAWCAYAAAABxvaqAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB
3RJTUUH3wYeFzIs1vtcMQAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAE0lEQVQI12P4//8/AxMDAw
NdCABMPwMo2ctnoQAAAABJRU5ErkJggg==
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAWCAYAAADJqhx8AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB
3RJTUUH3wYeFzI3XJ6V3QAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAANklEQVQ4y+2RsQ0AIAzDav
7/2VzQwoCY4iWbZSmo1QGoUgNMghvWaIejPQW/CrrNCylIwcOCDYfLNRcNer4SAAAAAElFTkSuQmCC
data: image/png;base64,R0lGODlhEAAQAOZ/APrkusOiYvvfqbiXWaV2G+jGhdq1b8GgYf3v1frw3vTUlsWkZNewbcSjY/DQk
ad4Hb6dXv3u0f3v1ObEgfPTlerJiP3w1v79+e7OkPrfrfnjuNOtZPrpydaxa+/YrvvdpP779ZxvFPvnwKKBQaFyF/369M2vdaqHRP
z58/HNh/vowufFhfroxO3OkPrluv779tK0e6JzGProwvrow9m4eOnIifPTlPDPkP78+Naxaf3v0/zowfXRi+bFhLWUVv379/rnwPv
szv3rye3LiPvnv+3MjPDasKiIS/789/3x2f747eXDg+7Mifvu0tu7f+/QkfDTnPXWmPrjsvrjtPbPgrqZW+/QlPz48K2EMv36866O
UPvowat8Ivvgq/Pbrvzgq/PguvrgrqN0Gda2evfYm9+7d/rpw9q6e/LSku/Rl/XVl/LSlfrkt+zVqe7Wqv3x1/bNffbOf59wFdS6i
f3u0vrqyP3owPvepfXQivDQkO/PkKh9K7STVf779P///////yH5BAEAAH8ALAAAAAAQABAAAAfNgH+Cg36FfoOIhH4JBxBghYl/hQ
kNAV0IVT5GkJKLCwtQaSsSdx9aR26Gcwt2IkQaNRI6dBERIzCFDSgWSW8WCDkbBnoOQ3uFARc/JQJfCAZlT0x4ZFyFBxdNQT9ZCBN
WKQoKUQ+FEDgcdTIAV14YDmg2CgSFA0hmQC5TLE4VRTdrKJAoxOeFCzZSwsw4U6BCizwUQhQyEaAPiAwCVNCY0FCNnA6GPAwYoETI
FgY9loiRA4dToTYnsOxg8CBGHE6ICvEYQ4AKzkidfgoKBAA7
Reference.identifier : An identifier for the other resource. This is used when there is
no way to reference the other resource directly, either because the entity is not available
through a FHIR server, or because there is no way for the author of the resource to convert
a known identifier to an actual location. There is no requirement that a Reference.identifier
point to something that is actually exposed as a FHIR instance, but it SHALL point to
a business concept that would be expected to be exposed as a FHIR instance, and that instance
would need to be of a FHIR resource type allowed by the reference.
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(data: image/png;base64,iVBORw0KG
goAAAANSUhEUgAAAyAAAAACCAYAAACg/LjIAAAAI0lEQVR42u3QIQEAAAACIL/6/4MvTAQOkLYBAAB4kAAAANwMad9AqkRjgNAAAA
AASUVORK5CYII=)
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAAWCAYAAAABxvaqAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB
3RJTUUH3wYeFzIs1vtcMQAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAE0lEQVQI12P4//8/AxMDAw
NdCABMPwMo2ctnoQAAAABJRU5ErkJggg==
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAWCAYAAADJqhx8AAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB
3RJTUUH3wYeFzME+lXFigAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAANklEQVQ4y+3OsRUAIAjEUO
L+O8cJABttJM11/x1qZAGqRBEVcNIqdWj1efDqQbb3HwwwwEfABmQUHSPM9dtDAAAAAElFTkSuQmCC
data: image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIW
XMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3gYBFzI0BrFQCwAAAERJREFUOMtj/P//PwMlgImBQjDwBrCcOnWKokBgYWBgYDCU+06W5i
8MUggvnH/EOVJjAW4AuQHJ+O75LYqikXE0LzAAALePEntTkEoSAAAAAElFTkSuQmCC
Reference.display : Plain text narrative that identifies the resource in addition to the
resource reference.
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
vertical-align: top; text-align : left; background-color: white; border: 0px #F0F0F0 solid;
padding:0px 4px 0px 4px
<?xml version="1.0" encoding="UTF-8"?>
Documentation for this format
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing
for access control, temporary unavailability, etc). Resolution can be either by retrieval
from the URL, or, where applicable by resource type, by treating an absolute reference
as a canonical URL and looking it up in a local registry/repository.
reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.tr
ace('ids'))
not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/
f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value,
'#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])
unique id for the element within a resource (for internal references). This may be any
string value that does not contain spaces.
<StructureDefinition xmlns="http://hl7.org/fhir">
<id value="Reference"/>
<text>
<status value="generated"/>
<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 class="hierarchy" 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">
<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 class="hierarchy" 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">
<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 class="hierarchy" 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">
<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 class="hierarchy" 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">
<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 class="hierarchy" 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">
<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 alt="doco" src="data:(snipped in html view)" style="background-color: inherit"/> </a> </span> </th> </tr> <tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color:
white">
<td class="hierarchy" 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/LjIAAAAJUlEQVR4Xu3IIQEAAAg
DsHd9/w4EQIOamFnaBgAA4MMKAACAKwNp30CqZFfFmwAAAABJRU5ErkJggg==)">
<img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: white; background-color: inherit" title="Element"/> <a href="references-definitions.html#Reference" title="Reference : A reference from one resource to another.">Reference</a> </td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="elementdefinition-definitions.html#ElementDefinition.isSummary" style="padding-left: 3px; padding-right: 3px; color: black; null; padding-left: 3px; padding-right:
3px; color: black; null" title="This element is included in summaries">Σ</a>
<a href="versions.html#std-process" 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" title="Standards Status = Normative">N</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px"/>
<td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="types.html#Element">Element</a> </td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">A reference from one resource to another
<br/> <span style="font-style: italic" title="ref-1">+ Rule: SHALL have a contained resource if a local reference is provided</span> <br/> <span style="font-style: italic" title="ref-2">+ Rule: At least one of reference, identifier and display SHALL be present (unless
an extension is provided).</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> <tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color:
#F7F7F7">
<td class="hierarchy" 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/LjIAAAALUlEQVR4Xu3IoREAIAw
EwfT6/ddA0GBAxO3NrLlKUj9263wAAAAvrgEAADClAVWFQIBRHMicAAAAAElFTkSuQmCC)">
<img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: #F7F7F7; background-color: inherit" title="Primitive Data Type"/> <a href="references-definitions.html#Reference.reference" title="Reference.reference : A reference to a location at which the other resource is
found. The reference may be a relative reference, in which case it is relative
to the service base URL, or an absolute URL that resolves to the location where
the resource is found. The reference may be version specific or not. If the reference
is not to a FHIR RESTful server, then it should be assumed to be version specific.
Internal fragment references (start with '#') refer to contained resources.">reference</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="elementdefinition-definitions.html#ElementDefinition.isSummary" style="padding-left: 3px; padding-right: 3px; color: black; null; padding-left: 3px; padding-right:
3px; color: black; null" title="This element is included in summaries">Σ</a>
<a href="conformance-rules.html#constraints" 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;" title="This element has or is affected by some invariants">C</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">0..1</td>
<td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="datatypes.html#string">string</a> </td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">Literal reference, Relative, internal or absolute URL
<br/> </td> </tr> <tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color:
white">
<td class="hierarchy" 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/LjIAAAALUlEQVR4Xu3IoREAIAw
EwfT6/ddA0GBAxO3NrLlKUj9263wAAAAvrgEAADClAVWFQIBRHMicAAAAAElFTkSuQmCC)">
<img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: white; background-color: inherit" title="Primitive Data Type"/> <a href="references-definitions.html#Reference.type" title="Reference.type : The expected type of the target of the reference. If both Reference.type
and Reference.reference are populated and Reference.reference is a FHIR URL, both
SHALL be consistent.
The type is the Canonical URL of Resource Definition that is the type this reference
refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/
e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient.
Absolute URLs are only allowed for logical models (and can only be used in references
in logical models, not resources).">type</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="elementdefinition-definitions.html#ElementDefinition.isSummary" style="padding-left: 3px; padding-right: 3px; color: black; null; padding-left: 3px; padding-right:
3px; color: black; null" title="This element is included in summaries">Σ</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">0..1</td>
<td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="datatypes.html#uri">uri</a> </td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">Type the reference refers to (e.g. "Patient") - must be a resource in
resources
<br/> Binding: <a href="valueset-resource-types.html" title="Aa resource (or, for logical models, the URI of the logical model).">Resource Types</a> ( <a href="terminologies.html#extensible" title="To be conformant, the concept in this element SHALL be from the specified value
set if any of the codes within the value set can apply to the concept being communicated.
If the value set does not cover the concept (based on human review), alternate
codings (or, data type allowing, text) may be included instead.">Extensible</a> )
<br/> </td> </tr> <tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color:
#F7F7F7">
<td class="hierarchy" 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/LjIAAAALUlEQVR4Xu3IoREAIAw
EwfT6/ddA0GBAxO3NrLlKUj9263wAAAAvrgEAADClAVWFQIBRHMicAAAAAElFTkSuQmCC)">
<img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: #F7F7F7; background-color: inherit" title="Data Type"/> <a href="references-definitions.html#Reference.identifier" title="Reference.identifier : An identifier for the target resource. This is used when
there is no way to reference the other resource directly, either because the entity
it represents is not available through a FHIR server, or because there is no way
for the author of the resource to convert a known identifier to an actual location.
There is no requirement that a Reference.identifier point to something that is
actually exposed as a FHIR instance, but it SHALL point to a business concept that
would be expected to be exposed as a FHIR instance, and that instance would need
to be of a FHIR resource type allowed by the reference.">identifier</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="elementdefinition-definitions.html#ElementDefinition.isSummary" style="padding-left: 3px; padding-right: 3px; color: black; null; padding-left: 3px; padding-right:
3px; color: black; null" title="This element is included in summaries">Σ</a>
<a href="conformance-rules.html#constraints" 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;" title="This element has or is affected by some invariants">C</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">0..1</td>
<td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="datatypes.html#Identifier">Identifier</a> </td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">Logical reference, when literal reference is not known
<br/> </td> </tr> <tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color:
white">
<td class="hierarchy" 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/LjIAAAAJUlEQVR4Xu3IIQEAAAg
DsHd9/w4EQIOamFnaBgAA4MMKAACAKwNp30CqZFfFmwAAAABJRU5ErkJggg==)">
<img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: inherit"/> <img alt="." class="hierarchy" src="data:(snipped in html view)" style="background-color: white; background-color: inherit" title="Primitive Data Type"/> <a href="references-definitions.html#Reference.display" title="Reference.display : Plain text narrative that identifies the resource in addition
to the resource reference.">display</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="elementdefinition-definitions.html#ElementDefinition.isSummary" style="padding-left: 3px; padding-right: 3px; color: black; null; padding-left: 3px; padding-right:
3px; color: black; null" title="This element is included in summaries">Σ</a>
<a href="languages.html#translatable" style="padding-left: 3px; padding-right: 3px; color: black; null; padding-left: 3px; padding-right:
3px; color: black; null" title="This element is a candidate for being translated">T</a>
<a href="conformance-rules.html#constraints" 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;" title="This element has or is affected by some invariants">C</a>
</td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">0..1</td>
<td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">
<a href="datatypes.html#string">string</a> </td> <td class="hierarchy" style="vertical-align: top; text-align : var(--ig-left,left); background-color: white;
border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px">Text alternative for the resource
<br/> </td> </tr> <tr> <td class="hierarchy" colspan="5"> <br/> <a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Legend for this format"> <img alt="doco" src="data:(snipped in html view)" style="background-color: inherit"/> Documentation for this format </a> </td> </tr> </table> </div> </text> <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status"> <valueCode value="normative"/> </extension> <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-type-characteristics"> <valueCode value="has-target"/> </extension> <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-wg"> <valueCode value="fhir"/> </extension> <url value="http://hl7.org/fhir/StructureDefinition/Reference"/> <version value="6.0.0-ballot3"/> <name value="Reference"/> <status value="active"/> <experimental value="false"/> <date value="2025-12-17T09:50:17+00:00"/> <publisher value="HL7 International / FHIR Infrastructure"/> <contact> <telecom> <system value="url"/> <value value="http://hl7.org/fhir"/> </telecom> </contact> <contact> <telecom> <system value="url"/> <value value="http://www.hl7.org/Special/committees/fiwg"/> </telecom> </contact> <description value="Reference Type: A reference from one resource to another."/> <jurisdiction> <coding> <system value="http://unstats.un.org/unsd/methods/m49/m49.htm"/> <code value="001"/> <display value="World"/> </coding> </jurisdiction> <fhirVersion value="6.0.0-ballot3"/> <mapping> <identity value="rim"/> <uri value="http://hl7.org/v3"/> <name value="RIM Mapping"/> </mapping> <kind value="complex-type"/> <abstract value="false"/> <type value="Reference"/> <baseDefinition value="http://hl7.org/fhir/StructureDefinition/DataType"/> <derivation value="specialization"/> <snapshot> <element id="Reference"> <path value="Reference"/> <short value="A reference from one resource to another"/> <definition value="A reference from one resource to another."/> <comment value="References SHALL be a reference to an actual FHIR resource, and SHALL be resolvable
(allowing for access control, temporary unavailability, etc.). Resolution can be
either by retrieval from the URL, or, where applicable by resource type, by treating
an absolute reference as a canonical URL and looking it up in a local registry/repository."/>
<min value="0"/> <max value="*"/> <base> <path value="Reference"/> <min value="0"/> <max value="*"/> </base> <constraint> <key value="ele-1"/> <severity value="error"/> <human value="All FHIR elements must have a @value or children"/> <expression value="hasValue() or (children().count() > id.count())"/> <source value="http://hl7.org/fhir/StructureDefinition/Element"/> </constraint> <constraint> <key value="ref-1"/> <severity value="error"/> <human value="SHALL have a contained resource if a local reference is provided"/> <expression value="reference.exists() implies (reference.startsWith('#').not() or (reference.substring(1).trace
('url') in %rootResource.contained.id.trace('ids')) or (reference='#' and %rootResource!=%reso
urce))"/>
<source value="http://hl7.org/fhir/StructureDefinition/Reference"/> </constraint> <constraint> <key value="ref-2"/> <severity value="error"/> <human value="At least one of reference, identifier and display SHALL be present (unless an extension
is provided)."/>
<expression value="reference.exists() or identifier.exists() or display.exists() or extension.exists()"/> <source value="http://hl7.org/fhir/StructureDefinition/Reference"/> </constraint> <isModifier value="false"/> <mapping> <identity value="rim"/> <map value="n/a,The target of a resource reference is a RIM entry point (Act, Role, or Entity)"/> </mapping> </element> <element id="Reference.id"> <path value="Reference.id"/> <representation value="xmlAttr"/> <short value="Unique id for inter-element referencing"/> <definition value="Unique id for the element within a resource (for internal references). This may
be any string value that does not contain spaces."/>
<min value="0"/> <max value="1"/> <base> <path value="Element.id"/> <min value="0"/> <max value="1"/> </base>
<type> <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type"> <valueUrl value="string"/> </extension> <code value="http://hl7.org/fhirpath/System.String"/> </type> <condition value="ele-1"/> <isModifier value="false"/> <isSummary value="false"/> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Reference.extension"> <path value="Reference.extension"/> <slicing> <discriminator> <type value="value"/> <path value="url"/> </discriminator> <description value="Extensions are always sliced by (at least) url"/> <rules value="open"/> </slicing> <short value="Additional content defined by implementations"/>
<definition value="May be used to represent additional information that is not part of the basic definition
of the element. In order to make the use of extensions safe and manageable, there is a
strict set of governance applied to the definition and use of extensions. Though any
implementer is allowed to define an extension, there is a set of requirements that SHALL
be met as part of the definition of the extension.
There can be no stigma associated with the use of extensions by any application, project,
or standard - regardless of the institution or jurisdiction that uses or defines the extensions.
The use of extensions is what allows the FHIR specification to retain a core level of
simplicity for everyone.
A reference to a location at which the other resource is found. The reference may be a
relative reference, in which case it is relative to the service base URL, or an absolute
URL that resolves to the location where the resource is found. The reference may be version
specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed
to be version specific. Internal fragment references (start with '#') refer to contained
resources.
Using absolute URLs provides a stable scalable approach suitable for a cloud/web context,
while using relative/logical references provides a flexible approach suitable for use
when trading across closed eco-system boundaries. Absolute URLs do not need to point
to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to
the structure "/[type]/[id]" then it should be assumed that the reference is
to a FHIR RESTful server.
An identifier for the other resource. This is used when there is no way to reference the
other resource directly, either because the entity is not available through a FHIR server,
or because there is no way for the author of the resource to convert a known identifier
to an actual location. There is no requirement that a Reference.identifier point to something
that is actually exposed as a FHIR instance, but it SHALL point to a business concept
that would be expected to be exposed as a FHIR instance, and that instance would need
to be of a FHIR resource type allowed by the reference.
When an identifier is provided in place of a reference, any system processing the reference
will only be able to resolve the identifier to a reference if it understands the business
context in which the identifier is used. Sometimes this is global (e.g. a national identifier)
but often it is not. For this reason, none of the useful mechanisms described for working
with references (e.g. chaining, includes) are possible, nor should servers be expected
to be able resolve the reference. Servers may accept an identifier based reference untouched,
resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.
When both an identifier and a literal reference are provided, the literal reference is
preferred. Applications processing the resource are allowed - but not required - to check
that the identifier matches the literal reference
Applications converting a logical reference to a literal reference may choose to leave
the logical reference present, or remove it.
This is generally not the same as the Resource.text of the referenced resource. The purpose
is to identify what's being referenced, not to fully describe it.
References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing
for access control, temporary unavailability, etc). Resolution can be either by retrieval
from the URL, or, where applicable by resource type, by treating an absolute reference
as a canonical URL and looking it up in a local registry/repository.
reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.tr
ace('ids'))
not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/
f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value,
'#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])
A reference to a location at which the other resource is found. The reference may be a
relative reference, in which case it is relative to the service base URL, or an absolute
URL that resolves to the location where the resource is found. The reference may be version
specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed
to be version specific. Internal fragment references (start with '#') refer to contained
resources.
Using absolute URLs provides a stable scalable approach suitable for a cloud/web context,
while using relative/logical references provides a flexible approach suitable for use
when trading across closed eco-system boundaries. Absolute URLs do not need to point
to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to
the structure "/[type]/[id]" then it should be assumed that the reference is
to a FHIR RESTful server.
An identifier for the other resource. This is used when there is no way to reference the
other resource directly, either because the entity is not available through a FHIR server,
or because there is no way for the author of the resource to convert a known identifier
to an actual location. There is no requirement that a Reference.identifier point to something
that is actually exposed as a FHIR instance, but it SHALL point to a business concept
that would be expected to be exposed as a FHIR instance, and that instance would need
to be of a FHIR resource type allowed by the reference.
When an identifier is provided in place of a reference, any system processing the reference
will only be able to resolve the identifier to a reference if it understands the business
context in which the identifier is used. Sometimes this is global (e.g. a national identifier)
but often it is not. For this reason, none of the useful mechanisms described for working
with references (e.g. chaining, includes) are possible, nor should servers be expected
to be able resolve the reference. Servers may accept an identifier based reference untouched,
resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.
When both an identifier and a literal reference are provided, the literal reference is
preferred. Applications processing the resource are allowed - but not required - to check
that the identifier matches the literal reference
Applications converting a logical reference to a literal reference may choose to leave
the logical reference present, or remove it.
This is generally not the same as the Resource.text of the referenced resource. The purpose
is to identify what's being referenced, not to fully describe it.
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 value="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 value="extensions"/> <alias value="user content"/> <min value="0"/> <max value="*"/> <base> <path value="Element.extension"/> <min value="0"/> <max value="*"/> </base> <type> <code value="Extension"/> </type> <constraint> <key value="ele-1"/> <severity value="error"/> <human value="All FHIR elements must have a @value or children"/> <expression value="hasValue() or (children().count() > id.count())"/> <source value="http://hl7.org/fhir/StructureDefinition/Element"/> </constraint> <isModifier value="false"/> <isSummary value="false"/> <mapping> <identity value="rim"/> <map value="n/a"/> </mapping> </element> <element id="Reference.reference"> <path value="Reference.reference"/> <short value="Literal reference, Relative, internal or absolute URL"/> <definition value="A reference to a location at which the other resource is found. The reference may
be a relative reference, in which case it is relative to the service base URL,
or an absolute URL that resolves to the location where the resource is found. The
reference may be version specific or not. If the reference is not to a FHIR RESTful
server, then it should be assumed to be version specific. Internal fragment references
(start with '#') refer to contained resources."/>
<comment value="Using absolute URLs provides a stable scalable approach suitable for a cloud/web
context, while using relative/logical references provides a flexible approach suitable
for use when trading across closed eco-system boundaries. Absolute URLs do not
need to point to a FHIR RESTful server, though this is the preferred approach.
If the URL conforms to the structure "[type]/[id]" then it should be
assumed that the reference is to a FHIR RESTful server."/>
<min value="0"/> <max value="1"/> <base> <path value="Reference.reference"/> <min value="0"/> <max value="1"/> </base> <type> <code value="string"/> </type> <condition value="ref-2"/> <condition value="ref-1"/> <constraint> <key value="ele-1"/> <severity value="error"/> <human value="All FHIR elements must have a @value or children"/> <expression value="hasValue() or (children().count() > id.count())"/> <source value="http://hl7.org/fhir/StructureDefinition/Element"/> </constraint> <isModifier value="false"/> <isSummary value="true"/> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Reference.type"> <path value="Reference.type"/> <short value="Type the reference refers to (e.g. "Patient") - must be a resource in
resources"/>
<definition value="The expected type of the target of the reference. If both Reference.type and Reference.refere
nce are populated and Reference.reference is a FHIR URL, both SHALL be consistent.
The type is the Canonical URL of Resource Definition that is the type this reference
refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/
e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient.
Absolute URLs are only allowed for logical models (and can only be used in references
in logical models, not resources)."/>
<comment value="This element is used to indicate the type of the target of the reference. This
may be used which ever of the other elements are populated (or not). In some cases,
the type of the target may be determined by inspection of the reference (e.g. a
known RESTful URL) or by resolving the target of the reference."/>
<min value="0"/> <max value="1"/> <base> <path value="Reference.type"/> <min value="0"/> <max value="1"/> </base> <type> <code value="uri"/> </type> <constraint> <key value="ele-1"/> <severity value="error"/> <human value="All FHIR elements must have a @value or children"/> <expression value="hasValue() or (children().count() > id.count())"/> <source value="http://hl7.org/fhir/StructureDefinition/Element"/> </constraint> <isModifier value="false"/> <isSummary value="true"/> <binding> <extension url="http://hl7.org/fhir/tools/StructureDefinition/binding-definition"> <valueMarkdown value="Aa resource (or, for logical models, the URI of the logical model)."/> </extension> <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName"> <valueString value="FHIRResourceTypeExt"/> </extension> <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-isCommonBinding"> <valueBoolean value="true"/> </extension> <strength value="extensible"/> <description value="Aa resource (or, for logical models, the URI of the logical model)."/> <valueSet value="http://hl7.org/fhir/ValueSet/resource-types"/> </binding> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Reference.identifier"> <path value="Reference.identifier"/> <short value="Logical reference, when literal reference is not known"/> <definition value="An identifier for the target resource. This is used when there is no way to reference
the other resource directly, either because the entity it represents is not available
through a FHIR server, or because there is no way for the author of the resource
to convert a known identifier to an actual location. There is no requirement that
a Reference.identifier point to something that is actually exposed as a FHIR instance,
but it SHALL point to a business concept that would be expected to be exposed as
a FHIR instance, and that instance would need to be of a FHIR resource type allowed
by the reference."/>
<comment value="When an identifier is provided in place of a reference, any system processing the
reference will only be able to resolve the identifier to a reference if it understands
the business context in which the identifier is used. Sometimes this is global
(e.g. a national identifier) but often it is not. For this reason, none of the
useful mechanisms described for working with references (e.g. chaining, includes)
are possible, nor should servers be expected to be able resolve the reference.
Servers may accept an identifier based reference untouched, resolve it, and/or
reject it - see CapabilityStatement.rest.resource.referencePolicy.
When both an identifier and a literal reference are provided, the literal reference
is preferred. Applications processing the resource are allowed - but not required
- to check that the identifier matches the literal reference
Applications converting a logical reference to a literal reference may choose to
leave the logical reference present, or remove it.
Reference is intended to point to a structure that can potentially be expressed
as a FHIR resource, though there is no need for it to exist as an actual FHIR resource
instance - except in as much as an application wishes to actual find the target
of the reference. The content referred to be the identifier must meet the logical
constraints implied by any limitations on what resource types are permitted for
the reference. For example, it would not be legitimate to send the identifier
for a drug prescription if the type were Reference(Observation|DiagnosticReport).
One of the use-cases for Reference.identifier is the situation where no FHIR representation
exists (where the type is Reference (Any).
This element only allows for a single identifier. In the case where additional
identifiers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifi
er](https://build.fhir.org/ig/HL7/fhir-extensions/StructureDefinition-additionalIdentifier.htm
l) extension."/>
<min value="0"/> <max value="1"/> <base> <path value="Reference.identifier"/> <min value="0"/> <max value="1"/> </base> <type> <code value="Identifier"/> </type> <condition value="ref-2"/> <constraint> <key value="ele-1"/> <severity value="error"/> <human value="All FHIR elements must have a @value or children"/> <expression value="hasValue() or (children().count() > id.count())"/> <source value="http://hl7.org/fhir/StructureDefinition/Element"/> </constraint> <isModifier value="false"/> <isSummary value="true"/> <mapping> <identity value="rim"/> <map value=".identifier"/> </mapping> </element> <element id="Reference.display"> <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-translatable"> <valueBoolean value="true"/> </extension> <path value="Reference.display"/> <short value="Text alternative for the resource"/> <definition value="Plain text narrative that identifies the resource in addition to the resource reference."/> <comment value="This is generally not the same as the Resource.text of the referenced resource.
The purpose is to identify what's being referenced, not to fully describe it."/>
<min value="0"/> <max value="1"/> <base> <path value="Reference.display"/> <min value="0"/> <max value="1"/> </base> <type> <code value="string"/> </type> <condition value="ref-2"/> <constraint> <key value="ele-1"/> <severity value="error"/> <human value="All FHIR elements must have a @value or children"/> <expression value="hasValue() or (children().count() > id.count())"/> <source value="http://hl7.org/fhir/StructureDefinition/Element"/> </constraint> <isModifier value="false"/> <isSummary value="true"/> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> </snapshot> <differential> <element id="Reference"> <path value="Reference"/> <short value="A reference from one resource to another"/> <definition value="A reference from one resource to another."/> <comment value="References SHALL be a reference to an actual FHIR resource, and SHALL be resolvable
(allowing for access control, temporary unavailability, etc.). Resolution can be
either by retrieval from the URL, or, where applicable by resource type, by treating
an absolute reference as a canonical URL and looking it up in a local registry/repository."/>
<min value="0"/> <max value="*"/> <constraint> <key value="ref-1"/> <severity value="error"/> <human value="SHALL have a contained resource if a local reference is provided"/> <expression value="reference.exists() implies (reference.startsWith('#').not() or (reference.substring(1).trace
('url') in %rootResource.contained.id.trace('ids')) or (reference='#' and %rootResource!=%reso
urce))"/>
<source value="http://hl7.org/fhir/StructureDefinition/Reference"/> </constraint> <constraint> <key value="ref-2"/> <severity value="error"/> <human value="At least one of reference, identifier and display SHALL be present (unless an extension
is provided)."/>
<expression value="reference.exists() or identifier.exists() or display.exists() or extension.exists()"/> <source value="http://hl7.org/fhir/StructureDefinition/Reference"/> </constraint> <mapping> <identity value="rim"/> <map value="The target of a resource reference is a RIM entry point (Act, Role, or Entity)"/> </mapping> </element> <element id="Reference.reference"> <path value="Reference.reference"/> <short value="Literal reference, Relative, internal or absolute URL"/> <definition value="A reference to a location at which the other resource is found. The reference may
be a relative reference, in which case it is relative to the service base URL,
or an absolute URL that resolves to the location where the resource is found. The
reference may be version specific or not. If the reference is not to a FHIR RESTful
server, then it should be assumed to be version specific. Internal fragment references
(start with '#') refer to contained resources."/>
<comment value="Using absolute URLs provides a stable scalable approach suitable for a cloud/web
context, while using relative/logical references provides a flexible approach suitable
for use when trading across closed eco-system boundaries. Absolute URLs do not
need to point to a FHIR RESTful server, though this is the preferred approach.
If the URL conforms to the structure "[type]/[id]" then it should be
assumed that the reference is to a FHIR RESTful server."/>
<min value="0"/> <max value="1"/> <type> <code value="string"/> </type> <condition value="ref-2"/> <condition value="ref-1"/> <isSummary value="true"/> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Reference.type"> <path value="Reference.type"/> <short value="Type the reference refers to (e.g. "Patient") - must be a resource in
resources"/>
<definition value="The expected type of the target of the reference. If both Reference.type and Reference.refere
nce are populated and Reference.reference is a FHIR URL, both SHALL be consistent.
The type is the Canonical URL of Resource Definition that is the type this reference
refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/
e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient.
Absolute URLs are only allowed for logical models (and can only be used in references
in logical models, not resources)."/>
<comment value="This element is used to indicate the type of the target of the reference. This
may be used which ever of the other elements are populated (or not). In some cases,
the type of the target may be determined by inspection of the reference (e.g. a
known RESTful URL) or by resolving the target of the reference."/>
<min value="0"/> <max value="1"/> <type> <code value="uri"/> </type> <isSummary value="true"/> <binding> <extension url="http://hl7.org/fhir/tools/StructureDefinition/binding-definition"> <valueMarkdown value="Aa resource (or, for logical models, the URI of the logical model)."/> </extension> <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName"> <valueString value="FHIRResourceTypeExt"/> </extension> <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-isCommonBinding"> <valueBoolean value="true"/> </extension> <strength value="extensible"/> <description value="Aa resource (or, for logical models, the URI of the logical model)."/> <valueSet value="http://hl7.org/fhir/ValueSet/resource-types"/> </binding> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> <element id="Reference.identifier"> <path value="Reference.identifier"/> <short value="Logical reference, when literal reference is not known"/> <definition value="An identifier for the target resource. This is used when there is no way to reference
the other resource directly, either because the entity it represents is not available
through a FHIR server, or because there is no way for the author of the resource
to convert a known identifier to an actual location. There is no requirement that
a Reference.identifier point to something that is actually exposed as a FHIR instance,
but it SHALL point to a business concept that would be expected to be exposed as
a FHIR instance, and that instance would need to be of a FHIR resource type allowed
by the reference."/>
<comment value="When an identifier is provided in place of a reference, any system processing the
reference will only be able to resolve the identifier to a reference if it understands
the business context in which the identifier is used. Sometimes this is global
(e.g. a national identifier) but often it is not. For this reason, none of the
useful mechanisms described for working with references (e.g. chaining, includes)
are possible, nor should servers be expected to be able resolve the reference.
Servers may accept an identifier based reference untouched, resolve it, and/or
reject it - see CapabilityStatement.rest.resource.referencePolicy.
When both an identifier and a literal reference are provided, the literal reference
is preferred. Applications processing the resource are allowed - but not required
- to check that the identifier matches the literal reference
Applications converting a logical reference to a literal reference may choose to
leave the logical reference present, or remove it.
Reference is intended to point to a structure that can potentially be expressed
as a FHIR resource, though there is no need for it to exist as an actual FHIR resource
instance - except in as much as an application wishes to actual find the target
of the reference. The content referred to be the identifier must meet the logical
constraints implied by any limitations on what resource types are permitted for
the reference. For example, it would not be legitimate to send the identifier
for a drug prescription if the type were Reference(Observation|DiagnosticReport).
One of the use-cases for Reference.identifier is the situation where no FHIR representation
exists (where the type is Reference (Any).
This element only allows for a single identifier. In the case where additional
identifiers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifi
er](https://build.fhir.org/ig/HL7/fhir-extensions/StructureDefinition-additionalIdentifier.htm
l) extension."/>
<min value="0"/> <max value="1"/> <type> <code value="Identifier"/> </type> <condition value="ref-2"/> <isSummary value="true"/> <mapping> <identity value="rim"/> <map value=".identifier"/> </mapping> </element> <element id="Reference.display"> <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-translatable"> <valueBoolean value="true"/> </extension> <path value="Reference.display"/> <short value="Text alternative for the resource"/> <definition value="Plain text narrative that identifies the resource in addition to the resource reference."/> <comment value="This is generally not the same as the Resource.text of the referenced resource.
The purpose is to identify what's being referenced, not to fully describe it."/>
<min value="0"/> <max value="1"/> <type> <code value="string"/> </type> <condition value="ref-2"/> <isSummary value="true"/> <mapping> <identity value="rim"/> <map value="N/A"/> </mapping> </element> </differential>
</
StructureDefinition
>
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.
|
Propose
a
change
Foundation