A reference to a document.

Usually, this is used for documents other than those defined by FHIR.

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content.

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.

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.

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.

Document identifier as assigned by the source of the document. This identifier is specific to this version of the document. This unique identifier may be used elsewhere to identify this version of the document.

See ITI TF-2x: Z.9.1.1 Identifier and CDA root plus extension.

The structure and format of this Id shall be consistent with the specification corresponding to the formatCode attribute. (e.g. for a DICOM standard document a 64-character numeric UID, for an HL7 CDA format a serialization of the CDA Document Id extension and root in the form "oid^extension", where OID is a 64 digits max, and the Id is a 16 UTF-8 char max. If the OID is coded without the extension then the '^' character shall not be included.).

Other identifiers associated with the document, including version independent identifiers.

When the DocumentReference.identifier carries the entryUUID then the DocumentReference.identifier use shall be ‘official’.

The status of this document reference.

approved -> status=current deprecated -> status=superseded

The status of the document reference.

The status of the underlying document.

These HL7 FHIR STU3 elements are not used in XDS, therefore would not be present.

Status of the underlying document.

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

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

A categorization for the type of document referenced - helps for indexing and searching. This may be implied by or derived from the code specified in the DocumentReference.type.

This is a metadata field from XDS/MHD.

Helps humans to assess whether the document is of interest when viewing a list of documents.

Who or what the document is about. The document 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 farm animals, or a set of patients that share a common exposure).

Not a contained resource. URL Points to an existing Patient Resource representing the XDS Affinity Domain Patient.

When the document was created.

Creation time is used for tracking, organizing versions and searching. This is the creation time of the document, not the source material on which it is based.

When the document reference was created.

Referencing/indexing time is used for tracking, organizing versions and searching.

Identifies who is responsible for adding the information to the document.

Expect the references Practitioner to have his Organization

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

These HL7 FHIR STU3 elements are not used in XDS, therefore would not be present.

Relationships that this document has with other document references that already exist.

See ITI TF-2c: 3.65.4.1.2.3

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.

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.

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

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

The type of relationship between documents.

The target document of this relationship.

Human-readable description of the source document. This is sometimes known as the "title".

What the document is about, rather than a terse summary of the document. It is commonly the case that records do not have a title and are collectively referred to by the display name of Record code (e.g. a "consultation" or "progress note").

Helps humans to assess whether the document is of interest.

A set of Security-Tag codes specifying the level of privacy/security of the Document. Note that DocumentReference.meta.security contains the security labels of the "reference" to the document, while DocumentReference.securityLabel contains a snapshot of the security labels on the document the reference refers to.

Note: This is NOT the DocumentReference.meta, as that holds the meta tags for the DocumentReference itself.

Security Labels from the Healthcare Privacy and Security Classification System.

Use of the Health Care Privacy/Security Classification (HCS) system of security-tag use is recommended.

The document and format referenced. There may be multiple content element repetitions, each with a different format.

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.

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.

The document or URL of the document along with critical metadata to prove content has integrity.

Identifies the type of the data in the attachment and allows a method to be chosen to interpret or render the data. Includes mime type parameters such as charset where appropriate.

The mime type of an attachment. Any valid mime type is allowed.

Processors of the data need to be able to know how to interpret the data.

The human language of the content. The value can be any valid value according to BCP 47.

A human language.

Users need to be able to choose between the languages in a set of attachments.

The actual data of the attachment - a sequence of bytes. In XML, represented using base64.

These HL7 FHIR STU3 elements are not used in XDS, therefore would not be present.

The data needs to able to be transmitted inline.

An alternative location where the data can be accessed.

If both data and url are provided, the url SHALL point to the same content as the data contains. Urls may be relative references or may reference transient locations such as a wrapping envelope using cid: though this has ramifications for using signatures. Relative URLs are interpreted relative to the service url, like a resource reference, rather than relative to the resource itself. If a URL is provided, it SHALL resolve to actual data.

The data needs to be transmitted by reference.

The date that the attachment was first created.

These HL7 FHIR STU3 elements are not used in XDS, therefore would not be present.

This is often tracked as an integrity issue for use of the attachment.

An identifier of the document encoding, structure, and template that the document conforms to beyond the base format indicated in the mimeType.

Note that while IHE mostly issues URNs for format types, not all documents can be identified by a URI.

The clinical context in which the document was prepared.

These values are primarily added to help with searching for interesting/relevant documents.

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.

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.

The time period over which the service that is described by the document was provided.

The start of the period. The boundary is inclusive.

If the low element is missing, the meaning is that the low boundary is not known.

The kind of facility where the patient was seen.

XDS Facility Type.

This property may convey specifics about the practice setting where the content was created, often reflecting the clinical specialty.

The value set for this content has an example binding because it is a value set decided by community policy. Other examples exist for consideration: * HITSP created the table HITSP/C80 Table 2-148 Clinical Specialty Value Set (a value set based upon SNOMED CT which is referenced by Direct (XDR and XDM for Direct Messaging Specification, Version 1), as well as Nationwide Health Information Network (NHIN). Query for Documents, Web Service Interface Specification, V 3.0, 07/27/2011 * ELGA (Austria) (ELGA CDA Implementie-rungsleitfäden Registrierung von CDA Dokumenten für ELGA mit IHE Cross-Enterprise Document Sharing: XDS Metadaten (XDSDocumentEntry), [1.2.40.0.34.7.6.3] * XDS Connect-a-thon practiceSettingCode.

Additional details about where the content was created (e.g. clinical specialty).

This is an important piece of metadata that providers often rely upon to quickly sort and/or filter out to find specific content.

The Patient Information as known when the document was published. May be a reference to a version specific, or contained.

Contained Patient resource with Patient.identifier.use element set to ‘usual’.

Indicates that the data within the XDS document entry be represented as a contained resource. See Section 4.5.4.4.7

Expect the references Practitioner to have his Organization

A reference to a document.

Usually, this is used for documents other than those defined by FHIR.

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

The only time that a resource does not have an id is when it is being submitted to the server using a create operation.

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.

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content.

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.

The base language in which the resource is written.

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).

A human language.

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.

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.

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.

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.

May be used to represent additional information that is not part of the basic definition of the resource. 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.

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.

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.

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.

Document identifier as assigned by the source of the document. This identifier is specific to this version of the document. This unique identifier may be used elsewhere to identify this version of the document.

See ITI TF-2x: Z.9.1.1 Identifier and CDA root plus extension.

The structure and format of this Id shall be consistent with the specification corresponding to the formatCode attribute. (e.g. for a DICOM standard document a 64-character numeric UID, for an HL7 CDA format a serialization of the CDA Document Id extension and root in the form "oid^extension", where OID is a 64 digits max, and the Id is a 16 UTF-8 char max. If the OID is coded without the extension then the '^' character shall not be included.).

Other identifiers associated with the document, including version independent identifiers.

When the DocumentReference.identifier carries the entryUUID then the DocumentReference.identifier use shall be ‘official’.

The status of this document reference.

approved -> status=current deprecated -> status=superseded

The status of the document reference.

The status of the underlying document.

These HL7 FHIR STU3 elements are not used in XDS, therefore would not be present.

Status of the underlying document.

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

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

A categorization for the type of document referenced - helps for indexing and searching. This may be implied by or derived from the code specified in the DocumentReference.type.

This is a metadata field from XDS/MHD.

Helps humans to assess whether the document is of interest when viewing a list of documents.

Who or what the document is about. The document 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 farm animals, or a set of patients that share a common exposure).

Not a contained resource. URL Points to an existing Patient Resource representing the XDS Affinity Domain Patient.

When the document was created.

Creation time is used for tracking, organizing versions and searching. This is the creation time of the document, not the source material on which it is based.

When the document reference was created.

Referencing/indexing time is used for tracking, organizing versions and searching.

Identifies who is responsible for adding the information to the document.

Expect the references Practitioner to have his Organization

Which person or organization authenticates that this document is valid.

Contained resource

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

These HL7 FHIR STU3 elements are not used in XDS, therefore would not be present.

Relationships that this document has with other document references that already exist.

See ITI TF-2c: 3.65.4.1.2.3

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

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.

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.

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.

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.

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

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

The type of relationship between documents.

The target document of this relationship.

Human-readable description of the source document. This is sometimes known as the "title".

What the document is about, rather than a terse summary of the document. It is commonly the case that records do not have a title and are collectively referred to by the display name of Record code (e.g. a "consultation" or "progress note").

Helps humans to assess whether the document is of interest.

A set of Security-Tag codes specifying the level of privacy/security of the Document. Note that DocumentReference.meta.security contains the security labels of the "reference" to the document, while DocumentReference.securityLabel contains a snapshot of the security labels on the document the reference refers to.

Note: This is NOT the DocumentReference.meta, as that holds the meta tags for the DocumentReference itself.

Security Labels from the Healthcare Privacy and Security Classification System.

Use of the Health Care Privacy/Security Classification (HCS) system of security-tag use is recommended.

The document and format referenced. There may be multiple content element repetitions, each with a different format.

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

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.

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.

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.

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.

The document or URL of the document along with critical metadata to prove content has integrity.

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

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.

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.

Identifies the type of the data in the attachment and allows a method to be chosen to interpret or render the data. Includes mime type parameters such as charset where appropriate.

The mime type of an attachment. Any valid mime type is allowed.

Processors of the data need to be able to know how to interpret the data.

The human language of the content. The value can be any valid value according to BCP 47.

A human language.

Users need to be able to choose between the languages in a set of attachments.

The actual data of the attachment - a sequence of bytes. In XML, represented using base64.

These HL7 FHIR STU3 elements are not used in XDS, therefore would not be present.

The data needs to able to be transmitted inline.

An alternative location where the data can be accessed.

If both data and url are provided, the url SHALL point to the same content as the data contains. Urls may be relative references or may reference transient locations such as a wrapping envelope using cid: though this has ramifications for using signatures. Relative URLs are interpreted relative to the service url, like a resource reference, rather than relative to the resource itself. If a URL is provided, it SHALL resolve to actual data.

The data needs to be transmitted by reference.

The number of bytes of data that make up this attachment (before base64 encoding, if that is done).

The size is calculated on the data prior to base64 encoding, if the data is base64 encoded.

Representing the size allows applications to determine whether they should fetch the content automatically in advance, or refuse to fetch it at all.

The calculated hash of the data using SHA-1. Represented using base64.

The IHE Document Sharing metadata element hash holds the SHA1 hash of the document. The hash is encoded in FHIR in base64Binary, whereas in XDS hexbinary is used. The hash is calculated on the data prior to base64 encoding, if the data is base64 encoded.

Included so that applications can verify that the contents of a location have not changed and so that a signature of the content can implicitly sign the content of an image without having to include the data in the instance or reference the url in the signature.

A label or set of text to display in place of the data.

Applications need a label to display to a human user in place of the actual data if the data cannot be rendered or perceived by the viewer.

The date that the attachment was first created.

These HL7 FHIR STU3 elements are not used in XDS, therefore would not be present.

This is often tracked as an integrity issue for use of the attachment.

An identifier of the document encoding, structure, and template that the document conforms to beyond the base format indicated in the mimeType.

Note that while IHE mostly issues URNs for format types, not all documents can be identified by a URI.

The clinical context in which the document was prepared.

These values are primarily added to help with searching for interesting/relevant documents.

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

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.

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.

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.

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.

Describes the clinical encounter or type of care that the document content is associated with.

When referenceIdList contains an encounter, and a FHIR Encounter is available, it may be referenced.

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.

An event can further specialize the act inherent in the type, such as where it is simply "Procedure Report" and the procedure was a "colonoscopy". If one or more event codes are included, they shall not conflict with the values inherent in the class or type elements as such a conflict would create an ambiguous situation.

This list of codes represents the main clinical acts being documented.

The time period over which the service that is described by the document was provided.

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

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.

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.

The start of the period. The boundary is inclusive.

If the low element is missing, the meaning is that the low boundary is not known.

The end of the period. If the end of the period is missing, it means that the period is ongoing. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time.

The high value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has a end value of 2012-02-03.

The kind of facility where the patient was seen.

XDS Facility Type.

This property may convey specifics about the practice setting where the content was created, often reflecting the clinical specialty.

The value set for this content has an example binding because it is a value set decided by community policy. Other examples exist for consideration: * HITSP created the table HITSP/C80 Table 2-148 Clinical Specialty Value Set (a value set based upon SNOMED CT which is referenced by Direct (XDR and XDM for Direct Messaging Specification, Version 1), as well as Nationwide Health Information Network (NHIN). Query for Documents, Web Service Interface Specification, V 3.0, 07/27/2011 * ELGA (Austria) (ELGA CDA Implementie-rungsleitfäden Registrierung von CDA Dokumenten für ELGA mit IHE Cross-Enterprise Document Sharing: XDS Metadaten (XDSDocumentEntry), [1.2.40.0.34.7.6.3] * XDS Connect-a-thon practiceSettingCode.

Additional details about where the content was created (e.g. clinical specialty).

This is an important piece of metadata that providers often rely upon to quickly sort and/or filter out to find specific content.

The Patient Information as known when the document was published. May be a reference to a version specific, or contained.

Contained Patient resource with Patient.identifier.use element set to ‘usual’.

Indicates that the data within the XDS document entry be represented as a contained resource. See Section 4.5.4.4.7

Related identifiers or resources associated with the DocumentReference.

May be identifiers or resources that caused the DocumentReference or referenced Document to be created.

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

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.

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.

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.

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.

Related identifier to this DocumentReference. If both id and ref are present they shall refer to the same thing.

See ITI TF-2x: Appendix E.3.1 on CXi mapping to FHIR Identifier

Related Resource to this DocumentReference. If both id and ref are present they shall refer to the same thing.

May be filled with URL pointers to Resources found in referenceIdList