eHealth Infrastructure (v2020.1)

StructureDefinition: ehealth-composition - Detailed Descriptions

Definitions for the ehealth-composition Profile.

1. Composition
Definition

A set of healthcare-related information that is assembled together into a single logical document that provides a single coherent statement of meaning, establishes its own context and that has clinical attestation with regard to who is making the statement. While a Composition defines the structure, it does not actually contain the content: rather the full content of a document is contained in a Bundle, of which the Composition is the first resource contained.

Control0..*
Comments

While the focus of this specification is on patient-specific clinical statements, this resource can also apply to other healthcare-related statements such as study protocol designs, healthcare invoices and other activities that are not necessarily patient-specific or clinical.

InvariantsDefined on this element
dom-1: If the resource is contained in another resource, it SHALL NOT contain any narrative (: contained.text.empty())
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 (: contained.where(('#'+id in %resource.descendants().reference).not()).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())
2. Composition.id
Definition

The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.

Control0..1
Typeid
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.

3. Composition.meta
Definition

The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content may not always be associated with version changes to the resource.

Control0..1
TypeMeta
4. Composition.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.

Control0..1
Typeuri
Is Modifiertrue
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.

This element is labelled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation.

5. Composition.language
Definition

The base language in which the resource is written.

Control0..1
BindingA human language.
The codes SHALL be taken from Common Languages; other codes may be used where these codes are not suitable
Max Binding: All Languages
Typecode
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).

6. Composition.text
Definition

A human-readable narrative that contains a summary of the resource, and may 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.

Control0..1 This element is affected by the following invariants: dom-1
TypeNarrative
Alternate Namesnarrative, html, xhtml, display
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 in formation is added later.

7. Composition.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.

Control0..*
TypeResource
Alternate Namesinline resources, anonymous resources, contained 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.

8. Composition.extension
Definition

An Extension

Control0..*
TypeExtension
SlicingThis element introduces a set of slices on Composition.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
  • value @ url
9. Composition.extension:authorOrganization
SliceNameauthorOrganization
Definition

Organization that authored the Composition

Control0..* This element is affected by the following invariants: ele-1
TypeExtension(authorOrganization) (Extension Type: Reference)
InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() | (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
10. Composition.extension:authorOrganization.id
Definition

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

Control0..1
Typestring
11. Composition.extension:authorOrganization.extension
Definition

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

Control0..*
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.

SlicingThis element introduces a set of slices on Composition.extension.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
  • value @ url
12. Composition.extension:authorOrganization.url
Definition

Source of the definition for the extension code - a logical name or a URL.

Control1..1
Typeuri
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 Valuehttp://ehealth.sundhed.dk/fhir/StructureDefinition/ehealth-composition-authorOrganization
13. Composition.extension:authorOrganization.value[x]
Definition

Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).

Control1..1
TypeReference
[x] NoteSee Choice of Data Types for further information about how to use [x]
SlicingThis element introduces a set of slices on Composition.extension.value[x]. The slices are unordered and Closed, and can be differentiated using the following discriminators:
  • type @ $this
14. Composition.extension:authorOrganization.value[x]:valueReference
SliceNamevalueReference
Definition

Value of extension - may be a resource or one of a constrained set of the data types (see Extensibility in the spec for list).

Control1..1
TypeReference(ehealth-organization)
[x] NoteSee Choice of Data Types for further information about how to use [x]
15. Composition.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. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Control0..*
TypeExtension
Is Modifiertrue
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.

16. Composition.identifier
Definition

Logical identifier for the composition, assigned when created. This identifier stays constant as the composition is changed over time.

NoteThis is a business identifier, not a resource identifier (see discussion)
Control0..1
TypeIdentifier
Comments

See discussion in resource definition for how these relate.

17. Composition.status
Definition

The workflow/clinical status of this composition. The status is a marker for the clinical standing of the document.

Control1..1
BindingThe workflow/clinical status of the composition.
The codes SHALL be taken from CompositionStatus
Typecode
Is Modifiertrue
Requirements

Need to be able to mark interim, amended, or withdrawn compositions or documents.

Comments

If a composition is marked as withdrawn, the compositions/documents in the series, or data from the composition or document series, should never be displayed to a user without being clearly marked as untrustworthy. The flag "entered-in-error" is why this element is labeled as a modifier of other elements.

Some reporting work flows require that the original narrative of a final document never be altered; instead, only new narrative can be added. The composition resource has no explicit status for explicitly noting whether this business rule is in effect. This would be handled by an extension if required.

18. Composition.type
Definition

Specifies the particular kind of composition (e.g. History and Physical, Discharge Summary, Progress Note). This usually equates to the purpose of making the composition.

Control1..1
BindingThe codes SHALL be taken from DocumentType
TypeCodeableConcept
Requirements

Key metadata element describing the composition, used in searching/filtering.

Comments

For Composition type, LOINC is ubiquitous and strongly endorsed by HL7. Most implementation guides will require a specific LOINC code, or use LOINC as an extensible binding.

19. Composition.class
Definition

A categorization for the type of the composition - helps for indexing and searching. This may be implied by or derived from the code specified in the Composition Type.

Control0..1
BindingThe codes SHALL be taken from DocumentClass
TypeCodeableConcept
Requirements

Helps humans to assess whether the composition is of interest when viewing an index of compositions or documents.

Comments

This is a metadata field from XDS/MHD.

20. Composition.subject
Definition

Who or what the composition is about. The composition can be about a person, (patient or healthcare practitioner), a device (e.g. a machine) or even a group of subjects (such as a document about a herd of livestock, or a set of patients that share a common exposure).

Control1..1
TypeReference(Resource)
Requirements

Essential metadata for searching for the composition. Identifies who and/or what the composition/document is about.

Comments

For clinical documents, this is usually the patient.

21. Composition.encounter
Definition

Describes the clinical encounter or type of care this documentation is associated with.

Control0..1
TypeReference(Encounter)
Requirements

Provides context for the composition and supports searching.

22. Composition.date
Definition

The composition editing time, when the composition was last logically changed by the author.

Control1..1
TypedateTime
Requirements

dateTime is used for tracking, organizing versions and searching.

Comments

The Last Modified Date on the composition may be after the date of the document was attested without being changed.

23. Composition.author
Definition

Identifies who is responsible for the information in the composition, not necessarily who typed it in.

Control1..*
TypeReference(ehealth-practitioner | ehealth-device | ehealth-patient | ehealth-relatedperson)
Requirements

Identifies who is responsible for the content.

24. Composition.title
Definition

Official human-readable label for the composition.

Control1..1
Typestring
Comments

For many compositions, the title is the same as the text or a display name of Composition.type (e.g. a "consultation" or "progress note"). Note that CDA does not make title mandatory, but there are no known cases where it is useful for title to be omitted, so it is mandatory here. Feedback on this requirement is welcome during the trial use period.

25. Composition.confidentiality
Definition

The code specifying the level of confidentiality of the Composition.

Control0..1
BindingCodes specifying the level of confidentiality of the composition.
The codes SHALL be taken from ConfidentialityClassification
Typecode
Is Modifiertrue
Comments

The exact use of this element, and enforcement and issues related to highly sensitive documents are out of scope for the base specification, and delegated to implementation profiles (see security section).

This element is labeled as a modifier because highly confidential documents must not be treated as if they are not.

26. Composition.attester
Definition

A participant who has attested to the accuracy of the composition/document.

Control0..*
TypeBackboneElement
Requirements

Identifies responsibility for the accuracy of the composition content.

Comments

Only list each attester once.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() | (children().count() > id.count()))
27. Composition.attester.id
Definition

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

Control0..1
Typestring
28. Composition.attester.extension
Definition

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

Control0..*
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.

29. Composition.attester.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 that contains it. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Control0..*
TypeExtension
Is Modifiertrue
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.

30. Composition.attester.mode
Definition

The type of attestation the authenticator offers.

Control1..*
BindingThe way in which a person authenticated a composition.
The codes SHALL be taken from CompositionAttestationMode
Typecode
Requirements

Indicates the level of authority of the attestation.

Comments

Use more than one code where a single attester has more than one mode (professional and legal are often paired).

31. Composition.attester.time
Definition

When the composition was attested by the party.

Control0..1
TypedateTime
Requirements

Identifies when the information in the composition was deemed accurate. (Things may have changed since then.).

32. Composition.attester.party
Definition

Who attested the composition in the specified way.

Control0..1
TypeReference(ehealth-patient | ehealth-practitioner | ehealth-organization)
Requirements

Identifies who has taken on the responsibility for accuracy of the composition content.

33. Composition.custodian
Definition

Identifies the organization or group who is responsible for ongoing maintenance of and access to the composition/document information.

Control0..1
TypeReference(ehealth-organization)
Requirements

Identifies where to go to find the current version, where to report issues, etc.

Comments

This is useful when documents are derived from a composition - provides guidance for how to get the latest version of the document. This is optional because this is sometimes not known by the authoring system, and can be inferred by context. However, it is important that this information be known when working with a derived document, so providing a custodian is encouraged.

34. Composition.relatesTo
Definition

Relationships that this composition has with other compositions or documents that already exist.

Control0..*
TypeBackboneElement
Comments

A document is a version specific composition.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() | (children().count() > id.count()))
35. Composition.relatesTo.id
Definition

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

Control0..1
Typestring
36. Composition.relatesTo.extension
Definition

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

Control0..*
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.

37. Composition.relatesTo.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 that contains it. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Control0..*
TypeExtension
Is Modifiertrue
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.

38. Composition.relatesTo.code
Definition

The type of relationship that this composition has with anther composition or document.

Control1..1
BindingThe type of relationship between documents.
The codes SHALL be taken from DocumentRelationshipType
Typecode
Comments

If this document appends another document, then the document cannot be fully understood without also accessing the referenced document.

39. Composition.relatesTo.target[x]
Definition

The target composition/document of this relationship.

Control1..1
TypeChoice of: Identifier, Reference(ehealth-composition)
[x] NoteSee Choice of Data Types for further information about how to use [x]
40. Composition.event
Definition

The clinical service, such as a colonoscopy or an appendectomy, being documented.

Control0..*
TypeBackboneElement
Requirements

Provides context for the composition and creates a linkage between a resource describing an event and the composition created describing the event.

Comments

The event needs to be consistent with the type element, though can provide further information if desired.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() | (children().count() > id.count()))
41. Composition.event.id
Definition

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

Control0..1
Typestring
42. Composition.event.extension
Definition

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

Control0..*
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.

43. Composition.event.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 that contains it. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Control0..*
TypeExtension
Is Modifiertrue
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.

44. Composition.event.code
Definition

This list of codes represents the main clinical acts, such as a colonoscopy or an appendectomy, being documented. In some cases, the event is inherent in the typeCode, such as a "History and Physical Report" in which the procedure being documented is necessarily a "History and Physical" act.

Control0..*
BindingThe codes SHALL be taken from EventTypeCodes
TypeCodeableConcept
Comments

An event can further specialize the act inherent in the typeCode, such as where it is simply "Procedure Report" and the procedure was a "colonoscopy". If one or more eventCodes are included, they SHALL NOT conflict with the values inherent in the classCode, practiceSettingCode or typeCode, as such a conflict would create an ambiguous situation. This short list of codes is provided to be used as key words for certain types of queries.

45. Composition.event.period
Definition

The period of time covered by the documentation. There is no assertion that the documentation is a complete representation for this period, only that it documents events during this time.

Control0..1
TypePeriod
46. Composition.event.detail
Definition

The description and/or reference of the event(s) being documented. For example, this could be used to document such a colonoscopy or an appendectomy.

Control0..*
TypeReference(Resource)
47. Composition.section
Definition

The root of the sections that make up the composition.

Control0..*
TypeBackboneElement
InvariantsDefined on this element
cmp-1: A section must at least one of text, entries, or sub-sections (: text.exists() or entry.exists() or section.exists())
cmp-2: A section can only have an emptyReason if it is empty (: emptyReason.empty() or entry.empty())
ele-1: All FHIR elements must have a @value or children (: hasValue() | (children().count() > id.count()))
48. Composition.section.id
Definition

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

Control0..1
Typestring
49. Composition.section.extension
Definition

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

Control0..*
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.

50. Composition.section.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 that contains it. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions.

Control0..*
TypeExtension
Is Modifiertrue
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.

51. Composition.section.title
Definition

The label for this particular section. This will be part of the rendered content for the document, and is often used to build a table of contents.

Control0..1
Typestring
Requirements

Section headings are often standardized for different types of documents. They give guidance to humans on how the document is organized.

Alternate Namesheader, label, caption
Comments

The title identifies the section for a human reader. The title must be consistent with the narrative of the resource that is the target of the section.content reference. Generally, sections SHOULD have titles, but in some documents, it is unnecessary or inappropriate. Typically, this is where a section has subsections that have their own adequately distinguishing title, or documents that only have a single section. Most Implementation Guides will make section title to be a required element.

52. Composition.section.code
Definition

A code identifying the kind of content contained within the section. This must be consistent with the section title.

Control0..1
BindingClassification of a section of a composition/document.
For example codes, see Document Section Codes
TypeCodeableConcept
Requirements

Provides computable standardized labels to topics within the document.

Comments

The code identifies the section for an automated processor of the document. This is particularly relevant when using profiles to control the structure of the document. If the section has content (instead of sub-sections), the section.code does not change the meaning or interpretation of the resource that is the content of the section in the comments for the section.code.

53. Composition.section.text
Definition

A human-readable narrative that contains the attested content of the section, 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.

Control0..1 This element is affected by the following invariants: cmp-1
TypeNarrative
Comments

Document profiles may define what content should be represented in the narrative to ensure clinical safety.

54. Composition.section.mode
Definition

How the entry list was prepared - whether it is a working list that is suitable for being maintained on an ongoing basis, or if it represents a snapshot of a list of items from another source, or whether it is a prepared list where items may be marked as added, modified or deleted.

Control0..1
BindingThe processing mode that applies to this section.
The codes SHALL be taken from ListMode
Typecode
Is Modifiertrue
Requirements

Sections are used in various ways, and it must be known in what way it is safe to use the entries in them.

Comments

This element is labeled as a modifier because a change list must not be mis-understood as a complete list.

55. Composition.section.orderedBy
Definition

Specifies the order applied to the items in the section entries.

Control0..1
BindingWhat order applies to the items in the entry.
The codes SHOULD be taken from List Order Codes
TypeCodeableConcept
Requirements

Important for presentation and rendering. Lists may be sorted to place more important information first or to group related entries.

Comments

Applications SHOULD render ordered lists in the order provided, but MAY allow users to re-order based on their own preferences as well. If there is no order specified, the order is unknown, though there may still be some order.

56. Composition.section.entry
Definition

A reference to the actual resource from which the narrative in the section is derived.

Control0..* This element is affected by the following invariants: cmp-2
TypeReference(Resource)
Comments

If there are no entries in the list, an emptyReason SHOULD be provided.

57. Composition.section.emptyReason
Definition

If the section is empty, why the list is empty. An empty section typically has some text explaining the empty reason.

Control0..1 This element is affected by the following invariants: cmp-2
BindingIf a section is empty, why it is empty.
The codes SHOULD be taken from List Empty Reasons
TypeCodeableConcept
Requirements

Allows capturing things like "none exist" or "not asked" which can be important for most lists.

Comments

The various reasons for an empty section make a significant interpretation to its interpretation. Note that this code is for use when the entire section content has been suppressed, and not for when individual items are omitted - implementers may consider using a text note or a flag on an entry in these cases.

58. Composition.section.section
Definition

A nested sub-section within this section.

Control0..* This element is affected by the following invariants: cmp-1
TypeSee Composition.section
Comments

Nested sections are primarily used to help human readers navigate to particular portions of the document.