2026 US Quality Core Implementation Guide
0.5.0 - cibuild US

2026 US Quality Core Implementation Guide, published by Office of the National Coordinator for Health Information Technology (ONC). This guide is not an authorized publication; it is the continuous build for version 0.5.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/FHIR/us-quality-core/ and changes regularly. See the Directory of published versions

## Resource Profile: USQualityCoreBodyStructure - Detailed Descriptions

Active as of 2026-05-15

Definitions for the us-quality-core-bodystructure resource profile.

- Key Elements Table
- Differential Elements Table
- Snapshot Elements Table

Guidance on how to interpret the contents of this table can be foundhere

0. BodyStructure
Definition | Record details about an anatomical structure. This resource may be used when a coded concept does not provide the necessary detail needed for the use case.
Short | Specific and identified anatomical structure
Control | 0..*
Is Modifier | false
Must Support | false
Summary | false
Alternate Names | anatomical location
Invariants | dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty()) dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()) dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()) dom-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty()) dom-6: A resource should have narrative for robust management (text.`div`.exists())
2. BodyStructure.implicitRules
Definition | A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.
Short | A set of rules under which this content was created
Comments | Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.
Control | 0..1
Type | uri
Is Modifier | true because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
4. BodyStructure.modifierExtension
Definition | May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it 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 is allowed to 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 | Extensions that cannot be ignored
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.
Control | 0..*
Type | Extension
Is Modifier | true because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Summary | false
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 Names | extensions, user content
Invariants | 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())
6. BodyStructure.active
Definition | Whether this body site is in active use.
Short | Whether this record is in active use
Comments | This element is labeled as a modifier because it may be used to mark that the resource was created in error.
Control | 10..1
Type | boolean
Is Modifier | true because This element is labelled as a modifier because it is a status element that can indicate that a record should not be treated as valid
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Requirements | Need to be able to mark a body site entry as not to be used because it was created in error.
Meaning if Missing | This resource is generally assumed to be active if no value is provided for the active element
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
8. BodyStructure.location
Definition | The anatomical location or region of the specimen, lesion, or body structure.
Short | Body site
Control | 10..1
Binding | The codes SHOULD be taken from For example codes, see SNOMEDCTBodyStructures http://hl7.org/fhir/ValueSet/body-site|4.0.1 (preferred to `http://hl7.org/fhir/ValueSet/body-site` )
Type | CodeableConcept
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
10. BodyStructure.locationQualifier
Definition | Qualifier to refine the anatomical location. These include qualifiers for laterality, relative location, directionality, number, and plane.
Short | Body site modifier
Control | 0..*
Binding | The codes SHOULD be taken from For example codes, see BodystructureLocationQualifier http://hl7.org/fhir/ValueSet/bodystructure-relative-location|4.0.1 (preferred to `http://hl7.org/fhir/ValueSet/bodystructure-relative-location` ) Concepts modifying the anatomic location Concepts modifying the anatomic location.
Type | CodeableConcept
Is Modifier | false
Summary | false
Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
12. BodyStructure.patient
Definition | The person to which the body site belongs.
Short | Who this is about
Control | 1..1
Type | Reference(US Quality Core Patient, Patient)
Is Modifier | false
Summary | true
Invariants | 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 foundhere

0. BodyStructure
Must Support | false
2. BodyStructure.active
Short | Whether this record is in active use
Control | 1..1
4. BodyStructure.location
Short | Body site
Control | 1..1
Binding | The codes SHOULD be taken from SNOMEDCTBodyStructures (preferred to `http://hl7.org/fhir/ValueSet/body-site` )
6. BodyStructure.locationQualifier
Short | Body site modifier
Binding | The codes SHOULD be taken from BodystructureLocationQualifier (preferred to `http://hl7.org/fhir/ValueSet/bodystructure-relative-location` ) Concepts modifying the anatomic location
8. BodyStructure.patient
Short | Who this is about
Type | Reference(US Quality Core Patient)

Guidance on how to interpret the contents of this table can be foundhere

0. BodyStructure
Definition | Record details about an anatomical structure. This resource may be used when a coded concept does not provide the necessary detail needed for the use case.
Short | Specific and identified anatomical structure
Control | 0..*
Is Modifier | false
Must Support | false
Summary | false
Alternate Names | anatomical location
Invariants | dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (`contained.contained.empty()`) dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (`contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()`) dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (`contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()`) dom-5: If a resource is contained in another resource, it SHALL NOT have a security label (`contained.meta.security.empty()`) dom-6: A resource should have narrative for robust management (`text.`div`.exists()`)
2. BodyStructure.id
Definition | The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.
Short | Logical id of this artifact
Comments | The only time that a resource does not have an id is when it is being submitted to the server using a create operation.
Control | 0..1
Type | id
Is Modifier | false
Summary | true
4. BodyStructure.meta
Definition | The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content might not always be associated with version changes to the resource.
Short | Metadata about the resource
Control | 0..1
Type | Meta
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
6. BodyStructure.implicitRules
Definition | A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.
Short | A set of rules under which this content was created
Comments | Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.
Control | 0..1
Type | uri
Is Modifier | true because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
8. BodyStructure.language
Definition | The base language in which the resource is written.
Short | Language of the resource content
Comments | Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource. Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute).
Control | 0..1
Binding | The codes SHOULD be taken from CommonLanguages (preferred to `http://hl7.org/fhir/ValueSet/languages|4.0.1` ) A human language.
Additional Bindings | Purpose
AllLanguages | Max Binding
Type | code
Is Modifier | false
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | false
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
10. BodyStructure.text
Definition | A human-readable narrative that contains a summary of the resource and can be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety.
Short | Text summary of the resource, for human interpretation
Comments | Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later.
Control | 0..1
Type | Narrative
Is Modifier | false
Summary | false
Alternate Names | narrative, html, xhtml, display
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
12. BodyStructure.contained
Definition | These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope.
Short | Contained, inline Resources
Comments | This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again. Contained resources may have profiles and tags In their meta elements, but SHALL NOT have security labels.
Control | 0..*
Type | Resource
Is Modifier | false
Summary | false
Alternate Names | inline resources, anonymous resources, contained resources
14. BodyStructure.extension
Definition | May be used to represent additional information that is not part of the basic definition of the resource. 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 | Additional content defined by implementations
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.
Control | 0..*
Type | Extension
Is Modifier | false
Summary | false
Alternate Names | extensions, user content
Invariants | 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()`)
16. BodyStructure.modifierExtension
Definition | May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it 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 is allowed to 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 | Extensions that cannot be ignored
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.
Control | 0..*
Type | Extension
Is Modifier | true because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Summary | false
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 Names | extensions, user content
Invariants | 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()`)
18. BodyStructure.identifier
Definition | Identifier for this instance of the anatomical structure.
Short | Bodystructure identifier
Note | This is a business identifier, not a resource identifier (see discussion)
Control | 0..*
Type | Identifier
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
20. BodyStructure.active
Definition | Whether this body site is in active use.
Short | Whether this record is in active use
Comments | This element is labeled as a modifier because it may be used to mark that the resource was created in error.
Control | 1..1
Type | boolean
Is Modifier | true because This element is labelled as a modifier because it is a status element that can indicate that a record should not be treated as valid
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Requirements | Need to be able to mark a body site entry as not to be used because it was created in error.
Meaning if Missing | This resource is generally assumed to be active if no value is provided for the active element
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
22. BodyStructure.morphology
Definition | The kind of structure being represented by the body structure at `BodyStructure.location`. This can define both normal and abnormal morphologies.
Short | Kind of Structure
Comments | The minimum cardinality of 0 supports the use case of specifying a location without defining a morphology.
Control | 0..1
Binding | For example codes, see SNOMEDCTMorphologicAbnormalities (example to `http://hl7.org/fhir/ValueSet/bodystructure-code|4.0.1` ) Codes describing anatomic morphology.
Type | CodeableConcept
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
24. BodyStructure.location
Definition | The anatomical location or region of the specimen, lesion, or body structure.
Short | Body site
Control | 1..1
Binding | The codes SHOULD be taken from SNOMEDCTBodyStructures (preferred to `http://hl7.org/fhir/ValueSet/body-site` )
Type | CodeableConcept
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
26. BodyStructure.locationQualifier
Definition | Qualifier to refine the anatomical location. These include qualifiers for laterality, relative location, directionality, number, and plane.
Short | Body site modifier
Control | 0..*
Binding | The codes SHOULD be taken from BodystructureLocationQualifier (preferred to `http://hl7.org/fhir/ValueSet/bodystructure-relative-location` ) Concepts modifying the anatomic location
Type | CodeableConcept
Is Modifier | false
Summary | false
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
28. BodyStructure.description
Definition | A summary, characterization or explanation of the body structure.
Short | Text description
Comments | This description could include any visual markings used to orientate the viewer e.g. external reference points, special sutures, ink markings.
Control | 0..1
Type | string
Is Modifier | false
Primitive Value | This primitive element may be present, or absent, or replaced by an extension
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
30. BodyStructure.image
Definition | Image or images used to identify a location.
Short | Attached images
Control | 0..*
Type | Attachment
Is Modifier | false
Summary | false
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)
32. BodyStructure.patient
Definition | The person to which the body site belongs.
Short | Who this is about
Control | 1..1
Type | Reference(US Quality Core Patient)
Is Modifier | false
Summary | true
Invariants | ele-1: All FHIR elements must have a @value or children (`hasValue() or (children().count() > id.count())`)