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Extension: allowedUnits

URL for this extension:

http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits

Status: draft. Extension maintained by: Health Level Seven, Inc. - FHIR Core WG

Identifies the units of measure in which the element should be captured or expressed.

Comment:

Use a value set if more than one unit of measure is possible. Value sets will typically be short enough to display in a drop-down selection list.

Context of Use: Use on Element ID ElementDefinition

Extension Content

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• Full Structure
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• JSON
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Summary

Name	Flags	Card.	Type	Description & Constraints
allowedUnits		0..1	CodeableConcept, canonical(ValueSet)	URL = http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits allowedUnits: Identifies the units of measure in which the element should be captured or expressed. Binding: UCUM Codes (required) Use on Element ID ElementDefinition
Documentation for this format

Full Structure

Name	Flags	Card.	Type	Description & Constraints
extension		0..1	Extension	URL = http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits allowedUnits: Identifies the units of measure in which the element should be captured or expressed. Use on Element ID ElementDefinition
extension	I	0..0
url		1..1	uri	"http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits"
value[x]	I	1..1		Value of extension Binding: UCUM Codes (required)
valueCodeableConcept			CodeableConcept
valueCanonical			canonical(ValueSet)
Documentation for this format

XML Template

<!-- allowedUnits -->

<extension xmlns="http://hl7.org/fhir"
     url="http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits" >
  <!-- from Element: extension -->
 <value[x]><!--  1..1 CodeableConcept|canonical Value of extension --></value[x]>
</extension>

JSON Template

{ // allowedUnits
  // from Element: extension
    "extension" : [ //  sliced by value:url  in the specified order, Open ]
    "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits", // R! 
// value[x]: Value of extension. One of these 2:
    "valueCodeableConcept" : { CodeableConcept } // C? R! Value of extension
    "valueCanonical" : "<canonical>", // C? R! Value of extension
  }

Summary

Name	Flags	Card.	Type	Description & Constraints
allowedUnits		0..1	CodeableConcept, canonical(ValueSet)	URL = http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits allowedUnits: Identifies the units of measure in which the element should be captured or expressed. Binding: UCUM Codes (required) Use on Element ID ElementDefinition
Documentation for this format

Full Structure

Name	Flags	Card.	Type	Description & Constraints
extension		0..1	Extension	URL = http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits allowedUnits: Identifies the units of measure in which the element should be captured or expressed. Use on Element ID ElementDefinition
extension	I	0..0
url		1..1	uri	"http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits"
value[x]	I	1..1		Value of extension Binding: UCUM Codes (required)
valueCodeableConcept			CodeableConcept
valueCanonical			canonical(ValueSet)
Documentation for this format

XML Template

<!-- allowedUnits -->

<extension xmlns="http://hl7.org/fhir"
     url="http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits" >
  <!-- from Element: extension -->
 <value[x]><!--  1..1 CodeableConcept|canonical Value of extension --></value[x]>
</extension>

JSON Template

{ // allowedUnits
  // from Element: extension
    "extension" : [ //  sliced by value:url  in the specified order, Open ]
    "url" : "http://hl7.org/fhir/StructureDefinition/elementdefinition-allowedUnits", // R! 
// value[x]: Value of extension. One of these 2:
    "valueCodeableConcept" : { CodeableConcept } // C? R! Value of extension
    "valueCanonical" : "<canonical>", // C? R! Value of extension
  }

Constraints

• ele-1: All FHIR elements must have a @value or children (xpath: @value|f:*|h:div)
• ext-1: Must have either extensions or value[x], not both (xpath: exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')]))
• ele-1: On Extension.extension: All FHIR elements must have a @value or children (xpath on Extension.extension: @value|f:*|h:div)
• ext-1: On Extension.extension: Must have either extensions or value[x], not both (xpath on Extension.extension: exists(f:extension)!=exists(f:*[starts-with(local-name(.), "value")]))
• ele-1: On Extension.value[x]: All FHIR elements must have a @value or children (xpath on Extension.value[x]: @value|f:*|h:div)