Snapshot 3: Connectathon 32 Base

This is Snapshot #3 for FHIR R5, released to support Connectathon 32. For a full list of available versions, see the Directory of published versions.

StructureDefinition: elementdefinition-de - Detailed Descriptions

FHIR Infrastructure Work Group Maturity Level: 1Trial UseUse Context: Country: World, Country: World

Definitions for the elementdefinition-de Profile.

ElementDefinition
Element IdElementDefinition
Definition

Captures constraints on each element within the resource, profile, or extension.

Short DisplayDefinition of an element in a resource or extension
Cardinality0..*
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
eld-2RuleMin <= Maxmin.empty() or max.empty() or (max = '*') or iif(max != '*', min <= max.toInteger())
eld-5Ruleif the element definition has a contentReference, it cannot have type, defaultValue, fixed, pattern, example, minValue, maxValue, maxLength, or bindingcontentReference.empty() or (type.empty() and defaultValue.empty() and fixed.empty() and pattern.empty() and example.empty() and minValue.empty() and maxValue.empty() and maxLength.empty() and binding.empty())
eld-6RuleFixed value may only be specified if there is one typefixed.empty() or (type.count() <= 1)
eld-7RulePattern may only be specified if there is one typepattern.empty() or (type.count() <= 1)
eld-8RulePattern and fixed are mutually exclusivepattern.empty() or fixed.empty()
eld-11RuleBinding can only be present for coded elements, string, and uri if using FHIR-defined typesbinding.empty() or type.code.empty() or type.code.contains(":") or type.select((code = 'code') or (code = 'Coding') or (code='CodeableConcept') or (code = 'Quantity') or (code = 'string') or (code = 'uri') or (code = 'Duration')).exists()
eld-13RuleTypes must be unique by codetype.select(code).isDistinct()
eld-14RuleConstraints must be unique by keyconstraint.select(key).isDistinct()
eld-15Ruledefault value and meaningWhenMissing are mutually exclusivedefaultValue.empty() or meaningWhenMissing.empty()
eld-16RulesliceName must be composed of proper tokens separated by "/"sliceName.empty() or sliceName.matches('^[a-zA-Z0-9\\/\\-_\\[\\]\\@]+$')
eld-18RuleMust have a modifier reason if isModifier = true(isModifier.exists() and isModifier) implies isModifierReason.exists()
eld-19RuleElement names cannot include some special characters with a max of 64 characters,path.matches('^[^\\s\\.,:;\\\'"\\/|?!@#$%&*()\\[\\]{}]{1,64}(\\.[^\\s\\.,:;\\\'"\\/|?!@#$%&*()\\[\\]{}]{1,64}(\\[x\\])?(\\:[^\\s\\.]+)?)*$')
eld-20WarningElement names should be simple alphanumerics with a max of 64 characters or code generation tools may be brokenpath.matches('^[A-Za-z][A-Za-z0-9]{0,63}(\\.[a-z][A-Za-z0-9]{0,63}(\\[x])?)*$')
eld-22RulesliceIsConstraining can only appear if slicename is presentsliceIsConstraining.exists() implies sliceName.exists()
eld-24Guidelinepattern[x] should be used rather than fixed[x]fixed.exists().not()
This is (only) a best practice guideline because:

pattern[x] is generally preferred over fixed[x] because it doesn't preclude the use of id and additional extensions, though there are corner cases when it's appropriate to exclude those

eld-25WarningOrder has no meaning (and cannot be asserted to have meaning), so enforcing rules on order is improperorderMeaning.empty() implies slicing.where(rules='openAtEnd' or ordered).exists().not()
eld-27WarningMappings SHOULD be unique by keymapping.select(identity).isDistinct()
eld-28RuleCan't have valueAlternatives if mustHaveValue is truemustHaveValue.value implies valueAlternatives.empty()
ElementDefinition.id
Element IdElementDefinition.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typeid
ElementDefinition.extension
Element IdElementDefinition.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.extension(Question)
Element IdElementDefinition.extension:Question
Definition

The default/suggested phrasing to use when prompting a human to capture the data element in question form (e.g. In a survey).

Short DisplayPrompt for element phrased as question
Cardinality0..*
TypeExtension(question)
Comments

Question and label serve similar purposes in they both can be used to prompt for capturing a data element. Whether the question form or label form should be used will depend on the type of instrument being used to capture the information. The ordering is in order of preference. I.e. Most preferred question form is listed first. Note that this is for alternate phrasings of the question. Language translations are handled using the ISO 21090 string translation extensions.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
ElementDefinition.extension(AllowedUnits)
Element IdElementDefinition.extension:AllowedUnits
Definition

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

Short DisplayUnits to use for measured value
Cardinality0..1
TypeExtension(allowedUnits)
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
ElementDefinition.modifierExtension
Element IdElementDefinition.modifierExtension
Definition

May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

Short DisplayExtensions that cannot be ignored even if unrecognized
Cardinality0..*
TypeExtension
Is Modifiertrue (Reason: Modifier extensions are expected to modify the meaning or interpretation of the element that contains them)
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content, modifiers
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
ElementDefinition.path
Element IdElementDefinition.path
Definition

The path identifies the element and is expressed as a "."-separated list of ancestor elements, beginning with the name of the resource or extension.

Short DisplayPath of the element in the hierarchy of elements
Cardinality1..1
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.representation
Element IdElementDefinition.representation
Definition

Codes that define how this element is represented in instances, when the deviation varies from the normal case. No extensions are allowed on elements with a representation of 'xmlAttr', no matter what FHIR serialization format is used.

Short DisplayxmlAttr | xmlText | typeAttr | cdaText | xhtml
Cardinality0..0
Terminology Binding
The codes SHALL be taken from PropertyRepresentation
Typecode
Comments

In resources, this is rarely used except for special cases where the representation deviates from the normal, and can only be done in the base standard (and profiles must reproduce what the base standard does). This element is used quite commonly in Logical models when the logical models represent a specific serialization format (e.g. CDA, v2 etc.).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.sliceName
Element IdElementDefinition.sliceName
Definition

The name of this element definition slice, when slicing is working. The name must be a token with no dots or spaces. This is a unique name referring to a specific set of constraints applied to this element, used to provide a name to different slices of the same element.

Short DisplayName for this particular element (in a set of slices)
Cardinality0..1
Typestring
Requirements

May also be used for code generation purposes.

Comments

The name SHALL be unique within the structure within the context of the constrained resource element. (Though to avoid confusion, uniqueness across all elements is recommended.).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.sliceIsConstraining
Element IdElementDefinition.sliceIsConstraining
Definition

If true, indicates that this slice definition is constraining a slice definition with the same name in an inherited profile. If false, the slice is not overriding any slice in an inherited profile. If missing, the slice might or might not be overriding a slice in an inherited profile, depending on the sliceName.

Short DisplayIf this slice definition constrains an inherited slice definition (or not)
Cardinality0..1
Typeboolean
Requirements

Allows detection of a situation where an ancestor profile adds or removes slicing with the same name where that might impact the child profile.

Comments

If set to true, an ancestor profile SHALL have a slicing definition with this name. If set to false, no ancestor profile is permitted to have a slicing definition with this name.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.label
Element IdElementDefinition.label
Definition

A single preferred label which is the text to display beside the element indicating its meaning or to use to prompt for the element in a user display or form.

Short DisplayName for element to display with or prompt for element
Cardinality0..1
Typestring
Comments

See also the extension (http://hl7.org/fhir/StructureDefinition/elementdefinition-question)[extension-elementdefinition-question.html].

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.code
Element IdElementDefinition.code
Definition

A code that has the same meaning as the element in a particular terminology.

Short DisplayCorresponding codes in terminologies
Cardinality0..*
Terminology Binding
For example codes, see http://loinc.org/vs
TypeCoding
Requirements

Links the meaning of an element to an external terminology, and is very useful for searching and indexing.

Comments

The concept SHALL be properly aligned with the data element definition and other constraints, as defined in the code system, including relationships, of any code listed here. Where multiple codes exist in a terminology that could correspond to the data element, the most granular code(s) should be selected, so long as they are not more restrictive than the data element itself. The mappings may be used to provide more or less granular or structured equivalences in the code system.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.slicing
Element IdElementDefinition.slicing
Definition

Indicates that the element is sliced into a set of alternative definitions (i.e. in a structure definition, there are multiple different constraints on a single element in the base resource). Slicing can be used in any resource that has cardinality ..* on the base resource, or any resource with a choice of types. The set of slices is any elements that come after this in the element sequence that have the same path, until a shorter path occurs (the shorter path terminates the set).

Short DisplayThis element is sliced - slices follow
Cardinality0..0
TypeElement
Comments

The first element in the sequence, the one that carries the slicing, is the definition that applies to all the slices. This is based on the unconstrained element, but can apply any constraints as appropriate. This may include the common constraints on the children of the element.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.slicing.id
Element IdElementDefinition.slicing.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.slicing.extension
Element IdElementDefinition.slicing.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.slicing.discriminator
Element IdElementDefinition.slicing.discriminator
Definition

Designates which child elements are used to discriminate between the slices when processing an instance. If one or more discriminators are provided, the value of the child elements in the instance data SHALL completely distinguish which slice the element in the resource matches based on the allowed values for those elements in each of the slices.

Short DisplayElement values that are used to distinguish the slices
Cardinality0..*
TypeElement
Comments

If there is no discriminator, the content is hard to process, so this should be avoided.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.slicing.discriminator.id
Element IdElementDefinition.slicing.discriminator.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.slicing.discriminator.extension
Element IdElementDefinition.slicing.discriminator.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.slicing.discriminator.type
Element IdElementDefinition.slicing.discriminator.type
Definition

How the element value is interpreted when discrimination is evaluated.

Short Displayvalue | exists | type | profile | position
Cardinality1..1
Terminology Binding
The codes SHALL be taken from DiscriminatorType
Typecode
Comments

'pattern' is deprecated - it works exactly the same as 'value'.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.slicing.discriminator.path
Element IdElementDefinition.slicing.discriminator.path
Definition

A FHIRPath expression, using the simple subset of FHIRPath, that is used to identify the element on which discrimination is based.

Short DisplayPath to element value
Cardinality1..1
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.slicing.description
Element IdElementDefinition.slicing.description
Definition

A human-readable text description of how the slicing works. If there is no discriminator, this is required to be present to provide whatever information is possible about how the slices can be differentiated.

Short DisplayText description of how slicing works (or not)
Cardinality0..1
Typestring
Comments

If it's really not possible to differentiate them, the design should be re-evaluated to make the content usable.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.slicing.ordered
Element IdElementDefinition.slicing.ordered
Definition

If the matching elements have to occur in the same order as defined in the profile.

Short DisplayIf elements must be in same order as slices
Cardinality0..1
Typeboolean
Comments

Order should only be required when it is a pressing concern for presentation. Profile authors should consider making the order a feature of the rules about the narrative, not the rules about the data - requiring ordered data makes the profile much less re-usable.

Meaning if MissingOrder is not required unless specified
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.slicing.rules
Element IdElementDefinition.slicing.rules
Definition

Whether additional slices are allowed or not. When the slices are ordered, profile authors can also say that additional slices are only allowed at the end.

Short Displayclosed | open | openAtEnd
Cardinality1..1
Terminology Binding
The codes SHALL be taken from SlicingRules
Typecode
Comments

Allowing additional elements makes for a much for flexible template - it's open for use in wider contexts, but also means that the content of the resource is not closed, and applications have to decide how to handle content not described by the profile.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.short
Element IdElementDefinition.short
Definition

A concise description of what this element means (e.g. for use in autogenerated summaries).

Short DisplayConcise definition for space-constrained presentation
Cardinality0..0
Typestring
Comments

It is easy for a different short definition to change the meaning of an element and this can have nasty downstream consequences. Please be careful when providing short definitions in a profile.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.definition
Element IdElementDefinition.definition
Definition

Provides a complete explanation of the meaning of the data element for human readability. For the case of elements derived from existing elements (e.g. constraints), the definition SHALL be consistent with the base definition, but convey the meaning of the element in the particular context of use of the resource. (Note: The text you are reading is specified in ElementDefinition.definition).

Short DisplayFull formal definition as narrative text
Cardinality0..1
Typemarkdown
Requirements

To allow a user to state the usage of an element in a particular context.

Alternate NamesDescription
Comments

It is easy for a different definition to change the meaning of an element and this can have nasty downstream consequences. Please be careful when providing definitions in a profile.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.comment
Element IdElementDefinition.comment
Definition

Explanatory notes and implementation guidance about the data element, including notes about how to use the data properly, exceptions to proper use, etc. (Note: The text you are reading is specified in ElementDefinition.comment).

Short DisplayComments about the use of this element
Cardinality0..1
Typemarkdown
Comments

If it is possible to capture usage rules using constraints, that mechanism should be used in preference to this element.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.requirements
Element IdElementDefinition.requirements
Definition

This element is for traceability of why the element was created and why the constraints exist as they do. This may be used to point to source materials or specifications that drove the structure of this element.

Short DisplayWhy this resource has been created
Cardinality0..1
Typemarkdown
Comments

This element does not describe the usage of the element (that's done in comments), rather it's for traceability of why the element is either needed or why the constraints exist as they do. This may be used to point to source materials or specifications that drove the structure of this data element.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.alias
Element IdElementDefinition.alias
Definition

Identifies additional names by which this element might also be known.

Short DisplayOther names
Cardinality0..*
Typestring
Requirements

Allows for better easier recognition of the element by multiple communities, including international communities.

Alternate Namessynonym, other name
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.min
Element IdElementDefinition.min
Definition

The minimum number of times this element SHALL appear in the instance.

Short DisplayMinimum Cardinality
Cardinality0..1 This element is affected by the following invariants: eld-2
TypeunsignedInt
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.max
Element IdElementDefinition.max
Definition

The maximum number of times this element is permitted to appear in the instance.

Short DisplayMaximum Cardinality (a number or *)
Cardinality0..1 This element is affected by the following invariants: eld-3, eld-2
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
eld-3RuleMax SHALL be a number or "*"empty() or ($this = '*') or (toInteger() >= 0)
ElementDefinition.base
Element IdElementDefinition.base
Definition

Information about the base definition of the element, provided to make it unnecessary for tools to trace the deviation of the element through the derived and related profiles. When the element definition is not the original definition of an element - i.g. either in a constraint on another type, or for elements from a super type in a snap shot - then the information in provided in the element definition may be different to the base definition. On the original definition of the element, it will be same.

Short DisplayBase definition information for tools
Cardinality0..1
TypeElement
Comments

The base information does not carry any information that could not be determined from the path and related profiles, but making this determination requires both that the related profiles are available, and that the algorithm to determine them be available. For tooling simplicity, the base information must always be populated in element definitions in snap shots, even if it is the same.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.base.id
Element IdElementDefinition.base.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.base.extension
Element IdElementDefinition.base.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.base.path
Element IdElementDefinition.base.path
Definition

The Path that identifies the base element - this matches the ElementDefinition.path for that element. Across FHIR, there is only one base definition of any element - that is, an element definition on a StructureDefinition without a StructureDefinition.base.

Short DisplayPath that identifies the base element
Cardinality1..1
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.base.min
Element IdElementDefinition.base.min
Definition

Minimum cardinality of the base element identified by the path.

Short DisplayMin cardinality of the base element
Cardinality1..1
TypeunsignedInt
Comments

This is provided for consistency with max, and may affect code generation of mandatory elements of the base resource are generated differently (some reference implementations have done this).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.base.max
Element IdElementDefinition.base.max
Definition

Maximum cardinality of the base element identified by the path.

Short DisplayMax cardinality of the base element
Cardinality1..1
Typestring
Comments

This is provided to code generation, since the serialization representation in JSON differs depending on whether the base element has max > 1. Also, some forms of code generation may differ.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.contentReference
Element IdElementDefinition.contentReference
Definition

Identifies an element defined elsewhere in the definition whose content rules should be applied to the current element. ContentReferences bring across all the rules that are in the ElementDefinition for the element, including definitions, cardinality constraints, bindings, invariants etc.

Short DisplayReference to definition of content for the element
Cardinality0..0 This element is affected by the following invariants: eld-5
Typeuri
Comments

ContentReferences can only be defined in specializations, not constrained types, and they cannot be changed and always reference the non-constrained definition.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.type
Element IdElementDefinition.type
Definition

The data type or resource that the value of this element is permitted to be.

Short DisplayData type and Profile for this element
Cardinality0..* This element is affected by the following invariants: eld-13
TypeElement
Comments

The Type of the element can be left blank in a differential constraint, in which case the type is inherited from the resource. Abstract types are not permitted to appear as a type when multiple types are listed. (I.e. Abstract types cannot be part of a choice).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
eld-4RuleAggregation may only be specified if one of the allowed types for the element is a referenceaggregation.empty() or (code = 'Reference') or (code = 'canonical') or (code = 'CodeableReference')
eld-17RuletargetProfile is only allowed if the type is Reference or canonical(code='Reference' or code = 'canonical' or code = 'CodeableReference') or targetProfile.empty()
ElementDefinition.type.id
Element IdElementDefinition.type.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.type.extension
Element IdElementDefinition.type.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.type.code
Element IdElementDefinition.type.code
Definition

URL of Data type or Resource that is a(or the) type used for this element. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition e.g. "string" is a reference to http://hl7.org/fhir/StructureDefinition/string. Absolute URLs are only allowed in logical models.

Short DisplayData type or Resource (reference to definition)
Cardinality1..1
Terminology Binding
The codes SHALL be taken from Element Definition Types; other codes may be used where these codes are not suitable
Typeuri
Comments

If the element is a reference to another resource, this element contains "Reference", and the targetProfile element defines what resources can be referenced. The targetProfile may be a reference to the general definition of a resource (e.g. http://hl7.org/fhir/StructureDefinition/Patient).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.type.profile
Element IdElementDefinition.type.profile
Definition

Identifies a profile structure or implementation Guide that applies to the datatype this element refers to. If any profiles are specified, then the content must conform to at least one of them. The URL can be a local reference - to a contained StructureDefinition, or a reference to another StructureDefinition or Implementation Guide by a canonical URL. When an implementation guide is specified, the type SHALL conform to at least one profile defined in the implementation guide.

Short DisplayProfiles (StructureDefinition or IG) - one must apply
Cardinality0..0
Typecanonical(StructureDefinition)
Comments

It is possible to profile backbone element (e.g. part of a resource), using the profile-element extension.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.type.targetProfile
Element IdElementDefinition.type.targetProfile
Definition

Used when the type is "Reference" or "canonical", and identifies a profile structure or implementation Guide that applies to the target of the reference this element refers to. If any profiles are specified, then the content must conform to at least one of them. The URL can be a local reference - to a contained StructureDefinition, or a reference to another StructureDefinition or Implementation Guide by a canonical URL. When an implementation guide is specified, the target resource SHALL conform to at least one profile defined in the implementation guide.

Short DisplayProfile (StructureDefinition or IG) on the Reference/canonical target - one must apply
Cardinality0..*
Typecanonical(StructureDefinition)
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.type.aggregation
Element IdElementDefinition.type.aggregation
Definition

If the type is a reference to another resource, how the resource is or can be aggregated - is it a contained resource, or a reference, and if the context is a bundle, is it included in the bundle.

Short Displaycontained | referenced | bundled - how aggregated
Cardinality0..0 This element is affected by the following invariants: eld-4
Terminology Binding
The codes SHALL be taken from AggregationMode
Typecode
Comments

See Aggregation Rules for further clarification.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.type.versioning
Element IdElementDefinition.type.versioning
Definition

Whether this reference needs to be version specific or version independent, or whether either can be used.

Short Displayeither | independent | specific
Cardinality0..1
Terminology Binding
The codes SHALL be taken from ReferenceVersionRules
Typecode
Comments

The base specification never makes a rule as to which form is allowed, but implementation guides may do this. See Aggregation Rules for further clarification.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.defaultValue[x]
Element IdElementDefinition.defaultValue[x]
Definition

The value that should be used if there is no value stated in the instance (e.g. 'if not otherwise specified, the abstract is false').

Short DisplaySpecified value if missing from instance
Cardinality0..1 This element is affected by the following invariants: eld-15
TypeChoice of: base64Binary, boolean, canonical, code, date, dateTime, decimal, id, instant, integer, integer64, markdown, oid, positiveInt, string, time, unsignedInt, uri, url, uuid, Address, Age, Annotation, Attachment, CodeableConcept, CodeableReference, Coding, ContactPoint, Count, Distance, Duration, HumanName, Identifier, Money, Period, Quantity, Range, Ratio, RatioRange, Reference, SampledData, Signature, Timing, ContactDetail, DataRequirement, Expression, ParameterDefinition, RelatedArtifact, TriggerDefinition, UsageContext, Availability, ExtendedContactDetail, Dosage, Meta
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Comments

Specifying a default value means that the property can never been unknown - it must always have a value. Further, the default value can never be changed, or changed in constraints on content models. Defining default values creates many difficulties in implementation (e.g. when is a value missing?). For these reasons, default values are (and should be) used extremely sparingly.

No default values are ever defined in the FHIR specification, nor can they be defined in constraints ("profiles") on data types or resources. This element only exists so that default values may be defined in logical models. This element should only be used on child elements of complex data elements.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.meaningWhenMissing
Element IdElementDefinition.meaningWhenMissing
Definition

The Implicit meaning that is to be understood when this element is missing (e.g. 'when this element is missing, the period is ongoing').

Short DisplayImplicit meaning when this element is missing
Cardinality0..1 This element is affected by the following invariants: eld-15
Typemarkdown
Comments

Implicit meanings for missing values can only be specified on a resource, data type, or extension definition, and never in a profile that applies to one of these. An implicit meaning for a missing value can never be changed, and specifying one has the consequence that constraining its use in profiles eliminates use cases as possibilities, not merely moving them out of scope. This element should only be used on child elements of complex data elements.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.orderMeaning
Element IdElementDefinition.orderMeaning
Definition

If present, indicates that the order of the repeating element has meaning and describes what that meaning is. If absent, it means that the order of the element has no meaning.

Short DisplayWhat the order of the elements means
Cardinality0..1
Typestring
Comments

This element can only be asserted on repeating elements and can only be introduced when defining resources or data types. It can be further refined profiled elements but if absent in the base type, a profile cannot assert meaning.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.fixed[x]
Element IdElementDefinition.fixed[x]
Definition

Specifies a value that SHALL be exactly the value for this element in the instance, if present. For purposes of comparison, non-significant whitespace is ignored, and all values must be an exact match (case and accent sensitive). Missing elements/attributes must also be missing.

Short DisplayValue must be exactly this
Cardinality0..0 This element is affected by the following invariants: eld-5, eld-6, eld-8
TypeChoice of: base64Binary, boolean, canonical, code, date, dateTime, decimal, id, instant, integer, integer64, markdown, oid, positiveInt, string, time, unsignedInt, uri, url, uuid, Address, Age, Annotation, Attachment, CodeableConcept, CodeableReference, Coding, ContactPoint, Count, Distance, Duration, HumanName, Identifier, Money, Period, Quantity, Range, Ratio, RatioRange, Reference, SampledData, Signature, Timing, ContactDetail, DataRequirement, Expression, ParameterDefinition, RelatedArtifact, TriggerDefinition, UsageContext, Availability, ExtendedContactDetail, Dosage, Meta
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Comments

This is not recommended for Coding and CodeableConcept since these often have highly contextual properties such as version or display.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.pattern[x]
Element IdElementDefinition.pattern[x]
Definition

Specifies a value that each occurrence of the element in the instance SHALL follow - that is, any value in the pattern must be found in the instance, if the element has a value. Other additional values may be found too. This is effectively constraint by example.

When pattern[x] is used to constrain a primitive, it means that the value provided in the pattern[x] must match the instance value exactly.

When an element within a pattern[x] is used to constrain an array, it means that each element provided in the pattern[x] must (recursively) match at least one element from the instance array.

When pattern[x] is used to constrain a complex object, it means that each property in the pattern must be present in the complex object, and its value must recursively match -- i.e.,

  1. If primitive: it must match exactly the pattern value
  2. If a complex object: it must match (recursively) the pattern value
  3. If an array: it must match (recursively) the pattern value

If a pattern[x] is declared on a repeating element, the pattern applies to all repetitions. If the desire is for a pattern to apply to only one element or a subset of elements, slicing must be used. See Examples of Patterns for examples of pattern usage and the effect it will have.

Short DisplayValue must have at least these property values
Cardinality0..0 This element is affected by the following invariants: eld-5, eld-7, eld-8
TypeChoice of: base64Binary, boolean, canonical, code, date, dateTime, decimal, id, instant, integer, integer64, markdown, oid, positiveInt, string, time, unsignedInt, uri, url, uuid, Address, Age, Annotation, Attachment, CodeableConcept, CodeableReference, Coding, ContactPoint, Count, Distance, Duration, HumanName, Identifier, Money, Period, Quantity, Range, Ratio, RatioRange, Reference, SampledData, Signature, Timing, ContactDetail, DataRequirement, Expression, ParameterDefinition, RelatedArtifact, TriggerDefinition, UsageContext, Availability, ExtendedContactDetail, Dosage, Meta
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Comments

Mostly used for fixing values of CodeableConcept. In general, pattern[x] is not intended for use with primitive types, where is has the same meaning as fixed[x].

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.example
Element IdElementDefinition.example
Definition

A sample value for this element demonstrating the type of information that would typically be found in the element.

Short DisplayExample value (as defined for type)
Cardinality0..*
TypeElement
Comments

Examples will most commonly be present for data where it's not implicitly obvious from either the data type or value set what the values might be. (I.e. Example values for dates or quantities would generally be unnecessary.) If the example value is fully populated, the publication tool can generate an instance automatically.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.example.id
Element IdElementDefinition.example.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.example.extension
Element IdElementDefinition.example.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.example.label
Element IdElementDefinition.example.label
Definition

Describes the purpose of this example amoung the set of examples.

Short DisplayDescribes the purpose of this example
Cardinality1..1
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.example.value[x]
Element IdElementDefinition.example.value[x]
Definition

The actual value for the element, which must be one of the types allowed for this element.

Short DisplayValue of Example (one of allowed types)
Cardinality1..1
TypeChoice of: base64Binary, boolean, canonical, code, date, dateTime, decimal, id, instant, integer, integer64, markdown, oid, positiveInt, string, time, unsignedInt, uri, url, uuid, Address, Age, Annotation, Attachment, CodeableConcept, CodeableReference, Coding, ContactPoint, Count, Distance, Duration, HumanName, Identifier, Money, Period, Quantity, Range, Ratio, RatioRange, Reference, SampledData, Signature, Timing, ContactDetail, DataRequirement, Expression, ParameterDefinition, RelatedArtifact, TriggerDefinition, UsageContext, Availability, ExtendedContactDetail, Dosage, Meta
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.minValue[x]
Element IdElementDefinition.minValue[x]
Definition

The minimum allowed value for the element. The value is inclusive. This is allowed for the types date, dateTime, instant, time, decimal, integer, and Quantity.

Short DisplayMinimum Allowed Value (for some types)
Cardinality0..1
TypeChoice of: date, dateTime, instant, time, decimal, integer, integer64, positiveInt, unsignedInt, Quantity
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Comments

Except for date/date/instant, the type of the minValue[x] SHALL be the same as the specified type of the element. For the date/dateTime/instant values, the type of minValue[x] SHALL be either the same, or a Duration which specifies a relative time limit to the current time. The duration value is positive, and is subtracted from the current clock to determine the minimum allowable value. A minimum value for a Quantity is interpreted as an canonical minimum - e.g. you cannot provide 100mg if the minimum value is 10g.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.maxValue[x]
Element IdElementDefinition.maxValue[x]
Definition

The maximum allowed value for the element. The value is inclusive. This is allowed for the types date, dateTime, instant, time, decimal, integer, and Quantity.

Short DisplayMaximum Allowed Value (for some types)
Cardinality0..1
TypeChoice of: date, dateTime, instant, time, decimal, integer, integer64, positiveInt, unsignedInt, Quantity
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Comments

Except for date/date/instant, the type of the maxValue[x] SHALL be the same as the specified type of the element. For the date/dateTime/instant values, the type of maxValue[x] SHALL be either the same, or a Duration which specifies a relative time limit to the current time. The duration value is positive, and is added to the current clock to determine the maximum allowable value. A maximum value for a Quantity is interpreted as an canonical maximum - e.g. you cannot provide 10g if the maximum value is 50mg.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.maxLength
Element IdElementDefinition.maxLength
Definition

Indicates the maximum length in characters that is permitted to be present in conformant instances and which is expected to be supported by conformant consumers that support the element. maxLength SHOULD only be used on primitive data types that have a string representation (see Datatype characteristics).

Short DisplayMax length for string type data
Cardinality0..1
Typeinteger
Comments

Receivers are not required to reject instances that exceed the maximum length. The full length could be stored. In some cases, data might be truncated, though truncation should be undertaken with care and an understanding of the consequences of doing so. If not specified, there is no conformance expectation for length support.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.condition
Element IdElementDefinition.condition
Definition

A reference to an invariant that may make additional statements about the cardinality or value in the instance.

Short DisplayReference to invariant about presence
Cardinality0..*
Typeid
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.constraint
Element IdElementDefinition.constraint
Definition

Formal constraints such as co-occurrence and other constraints that can be computationally evaluated within the context of the instance.

Short DisplayCondition that must evaluate to true
Cardinality0..*
TypeElement
Comments

Constraints should be declared on the "context" element - the lowest element in the hierarchy that is common to all nodes referenced by the constraint.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
eld-21WarningConstraints should have an expression or else validators will not be able to enforce themexpression.exists()
eld-26RuleErrors cannot be suppressed(severity = 'error') implies suppress.empty()
ElementDefinition.constraint.id
Element IdElementDefinition.constraint.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.constraint.extension
Element IdElementDefinition.constraint.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.constraint.key
Element IdElementDefinition.constraint.key
Definition

Allows identification of which elements have their cardinalities impacted by the constraint. Will not be referenced for constraints that do not affect cardinality.

Short DisplayTarget of 'condition' reference above
Cardinality1..1 This element is affected by the following invariants: eld-14
Typeid
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.constraint.requirements
Element IdElementDefinition.constraint.requirements
Definition

Description of why this constraint is necessary or appropriate.

Short DisplayWhy this constraint is necessary or appropriate
Cardinality0..1
Typemarkdown
Comments

To be used if the reason for the constraint might not be intuitive to all implementers.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.constraint.severity
Element IdElementDefinition.constraint.severity
Definition

Identifies the impact constraint violation has on the conformance of the instance.

Short Displayerror | warning
Cardinality1..1
Terminology Binding
The codes SHALL be taken from ConstraintSeverity
Typecode
Comments

This allows constraints to be asserted as "shall" (error) and "should" (warning).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.constraint.suppress
Element IdElementDefinition.constraint.suppress
Definition

If true, indicates that the warning or best practice guideline should be suppressed.

Short DisplaySuppress warning or hint in profile
Cardinality0..1
Typeboolean
Comments

This element should only be present in a derived profile where a warning or hint has been determined to be spurious/incorrect. E.g. a warning encouraging the inclusion of an element that the profile explicitly prohibits.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.constraint.human
Element IdElementDefinition.constraint.human
Definition

Text that can be used to describe the constraint in messages identifying that the constraint has been violated.

Short DisplayHuman description of constraint
Cardinality1..1
Typestring
Comments

Should be expressed in business terms as much as possible.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.constraint.expression
Element IdElementDefinition.constraint.expression
Definition

A FHIRPath expression of constraint that can be executed to see if this constraint is met.

Short DisplayFHIRPath expression of constraint
Cardinality0..1
Typestring
Requirements

Used by validation tooling tests of the validity of the resource.

Comments

In the absense of an expression, the expression is likely not enforceable by validators, and might be missed by many systems.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.constraint.source
Element IdElementDefinition.constraint.source
Definition

A reference to the original source of the constraint, for traceability purposes.

Short DisplayReference to original source of constraint
Cardinality0..1
Typecanonical(StructureDefinition)
Comments

This is used when, e.g. rendering, where it is not useful to present inherited constraints when rendering the snapshot.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.mustHaveValue
Element IdElementDefinition.mustHaveValue
Definition

Specifies for a primitive data type that the value of the data type cannot be replaced by an extension.

Short DisplayFor primitives, that a value must be present - not replaced by an extension
Cardinality0..1
Typeboolean
Comments

Typical extensions that can be provided in place of a the value are data-absent-reason, nullflavor, OriginalText, and expression. Note that this element has no meaning when a value is provided, and extensions can be provided in addition to a value.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.valueAlternatives
Element IdElementDefinition.valueAlternatives
Definition

Specifies a list of extensions that can appear in place of a primitive value.

Short DisplayExtensions that are allowed to replace a primitive value
Cardinality0..*
Typecanonical(StructureDefinition)
Comments

if mustHaveValue is true, then this element should not be present, since no extensions are allowed in place of the value. Note that this element has no impact if the value is present.

Meaning if MissingIf this element is missing, then any extension can be used if it's context is appropriate
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.mustSupport
Element IdElementDefinition.mustSupport
Definition

If true, implementations that produce or consume resources SHALL provide "support" for the element in some meaningful way. Note that this is being phased out and replaced by obligations (see below). If false, the element may be ignored and not supported. If false, whether to populate or use the data element in any way is at the discretion of the implementation.

Short DisplayIf the element must be supported (discouraged - see obligations)
Cardinality0..1
Typeboolean
Requirements

Allows a profile to set expectations for system capabilities beyond merely respecting cardinality constraints.

Comments

"Something meaningful" is context dependent and impossible to describe in the base FHIR specification. For this reason, the mustSupport flag is never set to true by the FHIR specification itself - it is only set to true in profiles. A profile on a type can always make mustSupport = true if it is false in the base type but cannot make mustSupport = false if it is true in the base type. This is done in Resource Profiles, where the profile labels an element as mustSupport=true. When a profile does this, it SHALL also make clear exactly what kind of "support" is required, as this can mean many things. Note that an element that has the property IsModifier is not necessarily a "key" element (e.g. one of the important elements to make use of the resource), nor is it automatically mustSupport - however both of these things are more likely to be true for IsModifier elements than for other elements.

Meaning if MissingIn a base type, where the element is being defined for the first time, the element is assumed to be mustSupport = false. In a profile (a constraint on an existing type), if mustSupport is not specific in either the differential or the snapshot, the mustSupport value is not changed from the base definition. Note, though, that the snapshot SHOULD always populate the mustSupport value
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.obligation
Element IdElementDefinition.obligation
Definition

Documents obligations that apply to applications implementing this element. The obligations relate to application behaviour, not the content of the element itself in the resource instances that contain this element.

Short DisplayDocuments obligations for applications making use of this element
Cardinality0..*
TypeElement
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.obligation.id
Element IdElementDefinition.obligation.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.obligation.extension
Element IdElementDefinition.obligation.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.obligation.code
Element IdElementDefinition.obligation.code
Definition

Codes, potentially combination code, that describe the obligations that apply to implementing applications.

Short DisplayCombination code describing the nature of the obligation
Cardinality1..1
Terminology Binding
The codes SHALL be taken from Obligation Codes ValueSet; other codes may be used where these codes are not suitable
TypeCoding
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.obligation.actor
Element IdElementDefinition.obligation.actor
Definition

Actor(s) to which the obligation applies.

Short DisplayActor(s) this obligation applies to (all actors if none)
Cardinality0..*
Typecanonical(ActorDefinition)
Comments

If not actors are specified, then the obligation applies to all implementations.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.obligation.documentation
Element IdElementDefinition.obligation.documentation
Definition

Human readable documentation of the purpose or application of the obligation.

Short DisplayDocumentation of the purpose or application of the obligation
Cardinality0..1
Typemarkdown
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.obligation.usage
Element IdElementDefinition.obligation.usage
Definition

Qualifies the usage of the obligation. Typically obligations are qualified by jurisdiction, but they may also be qualified by gender, workflow status, clinical domain etc. The information to decide whether a usege context applies is usually outside the resource, determined by context, and this might present challenges for validation tooling.

Short DisplayQualifies the usage - jurisdiction, gender, workflow status etc
Cardinality0..*
TypeUsageContext
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.obligation.filter
Element IdElementDefinition.obligation.filter
Definition

A FHIRPath expression that restricts to the obligation to one of a set of repeats.

Short DisplayLimits obligation to some repeats by FHIRPath
Cardinality0..1
Typestring
Comments

This might be used to indicate obligations that apply to home phone number, and not to other phone numbers, for example.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.obligation.filterDocumentation
Element IdElementDefinition.obligation.filterDocumentation
Definition

Documents the FHIRPath expression for the benefit of users who are not familiar with FHIRPath.

Short DisplayDdescribes the intent of the filter (short)
Cardinality0..1
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.obligation.process
Element IdElementDefinition.obligation.process
Definition

A process that the obligation applies to. This might a canonical URL for an OperationDefinition, or some other reference.

Short DisplayThe obligation only applies when perfomring the indicated process
Cardinality0..*
Typeuri
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.isModifier
Element IdElementDefinition.isModifier
Definition

If true, the value of this element affects the interpretation of the element or resource that contains it, and the value of the element cannot be ignored. Typically, this is used for status, negation and qualification codes. The effect of this is that the element cannot be ignored by systems: they SHALL either recognize the element and process it, and/or a pre-determination has been made that it is not relevant to their particular system.

Short DisplayIf this modifies the meaning of other elements
Cardinality0..0
Typeboolean
Requirements

Allows elements to be introduced into a specification that can't safely be ignored by applications that don't recognize them.

Comments

Only the definition of an element can set IsModifier true - either the specification itself or where an extension is originally defined. Once set, it cannot be changed in derived profiles. An element/extension that has isModifier=true SHOULD also have a minimum cardinality of 1, so that there is no lack of clarity about what to do if it is missing. If it can be missing, the definition SHALL make the meaning of a missing element clear.

Meaning if MissingAn element is not a modifier element unless it is explicitly specified to be one
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.isModifierReason
Element IdElementDefinition.isModifierReason
Definition

Explains how that element affects the interpretation of the resource or element that contains it.

Short DisplayReason that this element is marked as a modifier
Cardinality0..1
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.isSummary
Element IdElementDefinition.isSummary
Definition

Whether the element should be included if a client requests a search with the parameter _summary=true.

Short DisplayInclude when _summary = true?
Cardinality0..0
Typeboolean
Requirements

Allow clients to search through large resources quickly.

Comments

Some resources include a set of simple metadata, and some very large data. This element is used to reduce the quantity of data returned in searches. Note that servers may pre-cache summarized resources for optimal performance. When a request is made with _summary=true, serializers only include elements marked as 'isSummary = true'. With a few exceptions (listed below), all datatype properties are included in the summary form. In resource and datatype definitions, if an element has a descendant marked as isSummary=true or if it satisfies both of the following conditions, it must be marked as isSummary=true:

  • is at the root or has a parent that is 'mustSupport'
  • has a minimum cardinality of 1 or is a modifier element

The following datatype properties are exceptions, and are not marked as isSummary:

  • Attachment.data
  • Signature.data, Signature.targetFormat, Signature.sigFormat
  • Narrative.status, Narrative.div
  • SampledData.data.
Meaning if MissingAn element is not included in the summary unless it is explicitly specified to be so
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding
Element IdElementDefinition.binding
Definition

Binds to a value set if this element is coded (code, Coding, CodeableConcept, Quantity), or the data types (string, uri).

Short DisplayValueSet details if this is coded
Cardinality0..1 This element is affected by the following invariants: eld-11
TypeElement
Comments

For a CodeableConcept, when no codes are allowed - only text, use a binding of strength "required" with a description explaining that no coded values are allowed and what sort of information to put in the "text" element.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
eld-12RuleValueSet SHALL start with http:// or https:// or urn: or #valueSet.exists() implies (valueSet.startsWith('http:') or valueSet.startsWith('https') or valueSet.startsWith('urn:') or valueSet.startsWith('#'))
eld-23Rulebinding SHALL have either description or valueSetdescription.exists() or valueSet.exists()
ElementDefinition.binding.id
Element IdElementDefinition.binding.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.binding.extension
Element IdElementDefinition.binding.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.binding.strength
Element IdElementDefinition.binding.strength
Definition

Indicates the degree of conformance expectations associated with this binding - that is, the degree to which the provided value set must be adhered to in the instances.

Short Displayrequired | extensible | preferred | example
Cardinality1..1
Terminology Binding
The codes SHALL be taken from BindingStrength
Typecode
Alternate Namesconformance, extensibility
Comments

For further discussion, see Using Terminologies.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.description
Element IdElementDefinition.binding.description
Definition

Describes the intended use of this particular set of codes.

Short DisplayIntended use of codes in the bound value set
Cardinality0..1
Typemarkdown
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.valueSet
Element IdElementDefinition.binding.valueSet
Definition

Refers to the value set that identifies the set of codes the binding refers to.

Short DisplaySource of value set
Cardinality0..1 This element is affected by the following invariants: eld-12
Typecanonical(ValueSet)
Comments

The reference may be version-specific or not (e.g. have a |[version] at the end of the canonical URL).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.additional
Element IdElementDefinition.binding.additional
Definition

Additional bindings that help applications implementing this element. Additional bindings do not replace the main binding but provide more information and/or context.

Short DisplayAdditional Bindings - more rules about the binding
Cardinality0..*
TypeElement
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.additional.id
Element IdElementDefinition.binding.additional.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.binding.additional.extension
Element IdElementDefinition.binding.additional.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.binding.additional.purpose
Element IdElementDefinition.binding.additional.purpose
Definition

The use of this additional binding.

Short Displaymaximum | minimum | required | extensible | candidate | current | preferred | ui | starter | component
Cardinality1..1
Terminology Binding
The codes SHALL be taken from Additional Binding Purpose ValueSet
Typecode
Comments

Conformance bindings are in addition to the base binding, not instead of it.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.additional.valueSet
Element IdElementDefinition.binding.additional.valueSet
Definition

The valueSet that is being bound for the purpose.

Short DisplayThe value set for the additional binding
Cardinality1..1
Typecanonical(ValueSet)
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.additional.documentation
Element IdElementDefinition.binding.additional.documentation
Definition

Documentation of the purpose of use of the bindingproviding additional information about how it is intended to be used.

Short DisplayDocumentation of the purpose of use of the binding
Cardinality0..1
Typemarkdown
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.additional.shortDoco
Element IdElementDefinition.binding.additional.shortDoco
Definition

Concise documentation - for summary tables.

Short DisplayConcise documentation - for summary tables
Cardinality0..1
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.additional.usage
Element IdElementDefinition.binding.additional.usage
Definition

Qualifies the usage of the binding. Typically bindings are qualified by jurisdiction, but they may also be qualified by gender, workflow status, clinical domain etc. The information to decide whether a usege context applies is usually outside the resource, determined by context, and this might present challenges for validation tooling.

Short DisplayQualifies the usage - jurisdiction, gender, workflow status etc
Cardinality0..*
TypeUsageContext
Comments

This specification does not define exactly how the context is determined for the usage; typically, this will be described in implementation guides.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.binding.additional.any
Element IdElementDefinition.binding.additional.any
Definition

Whether the binding applies to all repeats, or just to any one of them. This is only relevant for elements that can repeat.

Short DisplayWhether binding can applies to all repeats, or just one
Cardinality0..1
Typeboolean
Comments

A common pattern is to make a conformance binding to all repeats, and then make a binding that one of the repeats must conform to.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.mapping
Element IdElementDefinition.mapping
Definition

Identifies a concept from an external specification that roughly corresponds to this element.

Short DisplayMap element to another set of definitions
Cardinality0..*
TypeElement
Requirements

Provides guidance to implementers familiar with or converting content from other specifications.

Comments

Mappings are not necessarily specific enough for safe translation.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.mapping.id
Element IdElementDefinition.mapping.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

Short DisplayUnique id for inter-element referencing
Cardinality0..1
Typestring
ElementDefinition.mapping.extension
Element IdElementDefinition.mapping.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ext-1RuleMust have either extensions or value[x], not bothextension.exists() != value.exists()
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
ElementDefinition.mapping.identity
Element IdElementDefinition.mapping.identity
Definition

An internal reference to the definition of a mapping.

Short DisplayReference to mapping declaration
Cardinality1..1
Typeid
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.mapping.language
Element IdElementDefinition.mapping.language
Definition

Identifies the computable language in which mapping.map is expressed.

Short DisplayComputable language of mapping
Cardinality0..1
Terminology BindingBCP 13 (RFCs 2045, 2046, 2047, 4288, 4289 and 2049)
The codes SHALL be taken from Mime Types
Typecode
Comments

If omitted, then there can be no expectation of computational interpretation of the mapping.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.mapping.map
Element IdElementDefinition.mapping.map
Definition

Expresses what part of the target specification corresponds to this element.

Short DisplayDetails of the mapping
Cardinality1..1
Typestring
Comments

For most mappings, the syntax is undefined. Syntax will be provided for mappings to the RIM. Multiple mappings may be possible and may include constraints on other resource elements that identify when a particular mapping applies.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
ElementDefinition.mapping.comment
Element IdElementDefinition.mapping.comment
Definition

Comments that provide information about the mapping or its use.

Short DisplayComments about the mapping or its use
Cardinality0..1
Typemarkdown
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())