HL7.FHIR.UV.EXTENSIONS\Questionnaire Constraint - Definitions

This page is part of the FHIR Core Extensions Registry (v0.1.0: Releases Draft) based on FHIR v5.0.0. . For a full list of available versions, see the Directory of published versions

Extension: QConstraint - Detailed Descriptions

Page standards status: Trial-use

Maturity Level: 1

Definitions for the questionnaire-constraint extension.

Differential Elements Table
Key Elements Table
Snapshot Elements Table

Guidance on how to interpret the contents of this table can be found here.

1. Extension
Definition	An invariant that must be satisfied before responses to the questionnaire can be considered "complete". Optional Extension Element - found in all resources.
Comments	This maps to the ElementDefinition.constraint element. See additional guidance and examples in the SDC implementation guide.
2. Extension.extension:key
SliceName	key
Definition	Unique id for the constraint within the questionnaire.
Control	1..1
Type	Extension
3. Extension.extension:key.extension
Control	0..0
4. Extension.extension:key.url
Control	0..?
Type	uri
Fixed Value	key
5. Extension.extension:key.value[x]
Control	1..?
Type	id
[x] Note	See Choice of Data Types for further information about how to use [x]
6. Extension.extension:requirements
SliceName	requirements
Definition	An explanation of why this extension is required (for documentation purposes).
Control	0..1
Type	Extension
7. Extension.extension:requirements.extension
Control	0..0
8. Extension.extension:requirements.url
Control	0..?
Type	uri
Fixed Value	requirements
9. Extension.extension:requirements.value[x]
Control	1..?
Type	string
[x] Note	See Choice of Data Types for further information about how to use [x]
10. Extension.extension:severity
SliceName	severity
Definition	Indicates how serious violating the invariant is.
Control	1..1
Type	Extension
11. Extension.extension:severity.extension
Control	0..0
12. Extension.extension:severity.url
Control	0..?
Type	uri
Fixed Value	severity
13. Extension.extension:severity.value[x]
Control	1..?
Binding	The codes SHALL be taken from ConstraintSeverity How important the invariant is
Type	code
[x] Note	See Choice of Data Types for further information about how to use [x]
14. Extension.extension:expression
SliceName	expression
Definition	The FHIRPath expression of the rule for computable interpretation.
Control	1..1
Type	Extension
15. Extension.extension:expression.extension
Control	0..0
16. Extension.extension:expression.url
Control	0..?
Type	uri
Fixed Value	expression
17. Extension.extension:expression.value[x]
Control	1..?
Type	string
[x] Note	See Choice of Data Types for further information about how to use [x]
18. Extension.extension:human
SliceName	human
Definition	A free text expression of the rule to display to the user if the rule is violated.
Control	1..1
Type	Extension
19. Extension.extension:human.extension
Control	0..0
20. Extension.extension:human.url
Control	0..?
Type	uri
Fixed Value	human
21. Extension.extension:human.value[x]
Control	1..?
Type	string
[x] Note	See Choice of Data Types for further information about how to use [x]
22. Extension.extension:location
SliceName	location
Definition	Relative paths to the questions this rule is enforced against.
Control	0..*
Type	Extension
23. Extension.extension:location.extension
Control	0..0
24. Extension.extension:location.url
Control	0..?
Type	uri
Fixed Value	location
25. Extension.extension:location.value[x]
Control	1..?
Type	string
[x] Note	See Choice of Data Types for further information about how to use [x]
26. Extension.url
Fixed Value	http://hl7.org/fhir/StructureDefinition/questionnaire-constraint
27. Extension.value[x]
Control	0..01
[x] Note	See Choice of Data Types for further information about how to use [x]

Guidance on how to interpret the contents of this table can be found here.

1. Extension
Definition	An invariant that must be satisfied before responses to the questionnaire can be considered "complete". Optional Extension Element - found in all resources.
Control	0..*
Comments	This maps to the ElementDefinition.constraint element. See additional guidance and examples in the SDC implementation guide.
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
2. Extension.extension:key
SliceName	key
Definition	Unique id for the constraint within the questionnaire. 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.
Control	10..1*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
3. Extension.extension:key.extension
Definition	An Extension 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.
Control	0..0*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
4. Extension.extension:key.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	key
5. Extension.extension:key.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	10..1 This element is affected by the following invariants: ext-1
Type	Choice of: id, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, code, string, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
6. Extension.extension:requirements
SliceName	requirements
Definition	An explanation of why this extension is required (for documentation purposes). 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.
Control	0..1*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
7. Extension.extension:requirements.extension
Definition	An Extension 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.
Control	0..0*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
8. Extension.extension:requirements.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	requirements
9. Extension.extension:requirements.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	10..1 This element is affected by the following invariants: ext-1
Type	Choice of: string, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, code, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
10. Extension.extension:severity
SliceName	severity
Definition	Indicates how serious violating the invariant is. 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.
Control	10..1*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
11. Extension.extension:severity.extension
Definition	An Extension 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.
Control	0..0*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
12. Extension.extension:severity.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	severity
13. Extension.extension:severity.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	10..1 This element is affected by the following invariants: ext-1
Binding	The codes SHALL be taken from ConstraintSeverityFor codes, see (unbound) How important the invariant is
Type	Choice of: code, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, string, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
14. Extension.extension:expression
SliceName	expression
Definition	The FHIRPath expression of the rule for computable interpretation. 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.
Control	10..1*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
15. Extension.extension:expression.extension
Definition	An Extension 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.
Control	0..0*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
16. Extension.extension:expression.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	expression
17. Extension.extension:expression.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	10..1 This element is affected by the following invariants: ext-1
Type	Choice of: string, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, code, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
18. Extension.extension:human
SliceName	human
Definition	A free text expression of the rule to display to the user if the rule is violated. 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.
Control	10..1*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
19. Extension.extension:human.extension
Definition	An Extension 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.
Control	0..0*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
20. Extension.extension:human.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	human
21. Extension.extension:human.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	10..1 This element is affected by the following invariants: ext-1
Type	Choice of: string, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, code, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
22. Extension.extension:location
SliceName	location
Definition	Relative paths to the questions this rule is enforced against. 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.
Control	0..*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
23. Extension.extension:location.extension
Definition	An Extension 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.
Control	0..0*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
24. Extension.extension:location.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	location
25. Extension.extension:location.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	10..1 This element is affected by the following invariants: ext-1
Type	Choice of: string, date, Meta, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Availability, integer64, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, ExtendedContactDetail, CodeableConcept, ParameterDefinition, dateTime, code, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
26. Extension.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	http://hl7.org/fhir/StructureDefinition/questionnaire-constraint
27. Extension.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	0..01 This element is affected by the following invariants: ext-1
Type	Choice 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] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))

Guidance on how to interpret the contents of this table can be found here.

1. Extension
Definition	An invariant that must be satisfied before responses to the questionnaire can be considered "complete".
Control	0..*
Comments	This maps to the ElementDefinition.constraint element. See additional guidance and examples in the SDC implementation guide.
2. Extension.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Control	0..1 This element is affected by the following invariants: ele-1
Type	id
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
3. Extension.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 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.
Control	0..*
Type	Extension
Summary	false
Alternate Names	extensions, 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	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
4. Extension.extension:key
SliceName	key
Definition	Unique id for the constraint within the questionnaire.
Control	1..1
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
5. Extension.extension:key.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Control	0..1 This element is affected by the following invariants: ele-1
Type	id
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
6. Extension.extension:key.extension
Definition	An Extension
Control	0..0
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
7. Extension.extension:key.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	key
8. Extension.extension:key.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	1..1 This element is affected by the following invariants: ext-1
Type	id
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
9. Extension.extension:requirements
SliceName	requirements
Definition	An explanation of why this extension is required (for documentation purposes).
Control	0..1
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
10. Extension.extension:requirements.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Control	0..1 This element is affected by the following invariants: ele-1
Type	id
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
11. Extension.extension:requirements.extension
Definition	An Extension
Control	0..0
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
12. Extension.extension:requirements.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	requirements
13. Extension.extension:requirements.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	1..1 This element is affected by the following invariants: ext-1
Type	string
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
14. Extension.extension:severity
SliceName	severity
Definition	Indicates how serious violating the invariant is.
Control	1..1
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
15. Extension.extension:severity.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Control	0..1 This element is affected by the following invariants: ele-1
Type	id
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
16. Extension.extension:severity.extension
Definition	An Extension
Control	0..0
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
17. Extension.extension:severity.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	severity
18. Extension.extension:severity.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	1..1 This element is affected by the following invariants: ext-1
Binding	The codes SHALL be taken from ConstraintSeverity How important the invariant is
Type	code
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
19. Extension.extension:expression
SliceName	expression
Definition	The FHIRPath expression of the rule for computable interpretation.
Control	1..1
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
20. Extension.extension:expression.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Control	0..1 This element is affected by the following invariants: ele-1
Type	id
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
21. Extension.extension:expression.extension
Definition	An Extension
Control	0..0
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
22. Extension.extension:expression.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	expression
23. Extension.extension:expression.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	1..1 This element is affected by the following invariants: ext-1
Type	string
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
24. Extension.extension:human
SliceName	human
Definition	A free text expression of the rule to display to the user if the rule is violated.
Control	1..1
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
25. Extension.extension:human.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Control	0..1 This element is affected by the following invariants: ele-1
Type	id
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
26. Extension.extension:human.extension
Definition	An Extension
Control	0..0
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
27. Extension.extension:human.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	human
28. Extension.extension:human.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	1..1 This element is affected by the following invariants: ext-1
Type	string
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
29. Extension.extension:location
SliceName	location
Definition	Relative paths to the questions this rule is enforced against.
Control	0..*
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
30. Extension.extension:location.id
Definition	Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Control	0..1 This element is affected by the following invariants: ele-1
Type	id
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
31. Extension.extension:location.extension
Definition	An Extension
Control	0..0
Type	Extension
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count())) ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
Slicing	This element introduces a set of slices on Extension.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators: value @ url
32. Extension.extension:location.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	location
33. Extension.extension:location.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	1..1 This element is affected by the following invariants: ext-1
Type	string
[x] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
34. Extension.url
Definition	Source of the definition for the extension code - a logical name or a URL.
Control	1..1
Type	uri
XML Representation	In the XML format, this property is represented as an attribute.
Summary	false
Comments	The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.
Fixed Value	http://hl7.org/fhir/StructureDefinition/questionnaire-constraint
35. Extension.value[x]
Definition	Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).
Control	0..0 This element is affected by the following invariants: ext-1
Type	Choice 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] Note	See Choice of Data Types for further information about how to use [x]
Summary	false
Invariants	Defined on this element ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))