A request to convey information; e.g. the CDS system proposes that an alert be sent to a responsible provider, the CDS system proposes that the public health agency be notified about a reportable condition.

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.

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 its narrative along with other profiles, value sets, etc.

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, nor can they have their own independent transaction scope. This is allowed to be a Parameters resource if and only if it is referenced by a resource that provides context/meaning.

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.

An Extension

Specify that only digital invitations shall be sent, independent of opt-out options

Invitation action type

Flag to specify whether guardians shall be resolved from PU (Personuppgiftstjänsten) instead of using the referenced RelatedPerson in the patient resource

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 managable, 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).

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.

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.

Business identifiers assigned to this communication request by the performer or other systems which remain constant as the resource is updated and propagates from server to server.

This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number.

Allows identification of the communication request as it is known by various participating systems and in a way that remains consistent across servers.

The status of the proposal or order.

The status of the communication request.

Indicates the level of authority/intentionality associated with the CommunicationRequest and where the request fits into the workflow chain.

This element is expected to be immutable. E.g. A "proposal" instance should never change to be a "plan" instance or "order" instance. Instead, a new instance 'basedOn' the prior instance should be created with the new 'intent' value.

One exception to this is that the granularity of CommunicationRequest.intent is allowed to change. For example, a Request identified as an "order" might later be clarified to be a "filler-order". Or, in rarer cases (to meet recipient constraints), the reverse might also occur.

Codes indicating the degree of authority/intentionality associated with a request.

Proposals/recommendations, plans and orders all use the same structure and can exist in the same fulfillment chain.

If true indicates that the CommunicationRequest is asking for the specified action to not occur.

The attributes provided with the request qualify what is not to be done.

The patient or group that is the focus of this communication request.

Other resources that pertain to this communication request and to which this communication request should be associated.

Don't use CommunicationRequest.about element when a more specific element exists, such as basedOn, reasonReference, or replaces.

Text, attachment(s), or resource(s) to be communicated to the recipient.

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

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.

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.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

Text, attachment(s), or resource(s) to be communicated to the recipient.

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

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.

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.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

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.

BCP 13 (RFCs 2045, 2046, 2047, 4288, 4289 and 2049)

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

Text, attachment(s), or resource(s) to be communicated to the recipient.

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

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.

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.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

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.

BCP 13 (RFCs 2045, 2046, 2047, 4288, 4289 and 2049)

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

A request to convey information; e.g. the CDS system proposes that an alert be sent to a responsible provider, the CDS system proposes that the public health agency be notified about a reportable condition.

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

Within the context of the FHIR RESTful interactions, the resource has an id except for cases like the create and conditional update. Otherwise, the use of the resouce id depends on the given use case.

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.

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. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

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 version specific identifier, as it appears in the version portion of the URL. This value changes when the resource is created, updated, or deleted.

The server assigns this value, and ignores what the client specifies, except in the case that the server is imposing version integrity on updates/deletes.

When the resource last changed - e.g. when the version changed.

This element is generally omitted in instances submitted in a PUT or POST. Instead, it is populated in the response instance and when retrieving information using a GET. The server / resource manager sets this value; what a client provides is irrelevant. This is equivalent to the HTTP Last-Modified and SHOULD have the same value on a read interaction.

A uri that identifies the source system of the resource. This provides a minimal amount of Provenance information that can be used to track or differentiate the source of information in the resource. The source may identify another FHIR server, document, message, database, etc.

The exact use of the source (and the possible implied Provenance.entity.role and agent.role) is left to implementer discretion. Only one nominated source is allowed; for additional provenance details, a full Provenance resource should be used. The source may correspond to Provenance.entity.what[x] or Provenance.agent.who[x], though it may be a more general or abstract reference.

This element can be used to indicate where the current master source of a resource that has a canonical URL if the resource is no longer hosted at the canonical URL.

A list of profiles (references to StructureDefinition resources) that this resource claims to conform to. The URL is a reference to StructureDefinition.url.

It is up to the server and/or other infrastructure of policy to determine whether/how these claims are verified and/or updated over time. The list of profile URLs is a set.

Security labels applied to this resource. These tags connect specific resources to the overall security policy and infrastructure.

The security labels can be updated without changing the stated version of the resource. The list of security labels is a set. Uniqueness is based the system/code, and version and display are ignored.

Security Labels from the Healthcare Privacy and Security Classification System.

Tags applied to this resource. Tags are intended to be used to identify and relate resources to process and workflow, and applications are not required to consider the tags when interpreting the meaning of a resource.

The tags can be updated without changing the stated version of the resource. The list of tags is a set. Uniqueness is based the system/code, and version and display are ignored.

Codes that represent various types of tags, commonly workflow-related; e.g. "Needs review by Dr. Jones".

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.

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 its narrative along with other profiles, value sets, etc.

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).

IETF language tag for a human language

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.

Contained resources do not have a 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.

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, nor can they have their own independent transaction scope. This is allowed to be a Parameters resource if and only if it is referenced by a resource that provides context/meaning.

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.

An Extension

Specify that only digital invitations shall be sent, independent of opt-out options

Invitation action type

Flag to specify whether guardians shall be resolved from PU (Personuppgiftstjänsten) instead of using the referenced RelatedPerson in the patient resource

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 managable, 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).

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.

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.

Business identifiers assigned to this communication request by the performer or other systems which remain constant as the resource is updated and propagates from server to server.

This is a business identifier, not a resource identifier (see discussion). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number.

Allows identification of the communication request as it is known by various participating systems and in a way that remains consistent across servers.

A plan or proposal that is fulfilled in whole or in part by this request.

Allows tracing of authorization for the request and tracking whether proposals/recommendations were acted upon.

Completed or terminated request(s) whose function is taken by this new request.

The replacement could be because the initial request was immediately rejected (due to an issue) or because the previous request was completed, but the need for the action described by the request remains ongoing.

Allows tracing the continuation of a therapy or administrative process instantiated through multiple requests.

A shared identifier common to multiple independent Request instances that were activated/authorized more or less simultaneously by a single author. The presence of the same identifier on each request ties those requests together and may have business ramifications in terms of reporting of results, billing, etc. E.g. a requisition number shared by a set of lab tests ordered together, or a prescription number shared by all meds ordered at one time.

Requests are linked either by a "basedOn" relationship (i.e. one request is fulfilling another) or by having a common requisition. Requests that are part of the same requisition are generally treated independently from the perspective of changing their state or maintaining them after initial creation.

The status of the proposal or order.

The status of the communication request.

Captures the reason for the current state of the CommunicationRequest.

This is generally only used for "exception" statuses such as "on-hold" or "revoked". The reason why the CommunicationRequest was created at all is captured in reasonCode, not here.

Codes identifying the reason for the current state of a request.

Indicates the level of authority/intentionality associated with the CommunicationRequest and where the request fits into the workflow chain.

This element is expected to be immutable. E.g. A "proposal" instance should never change to be a "plan" instance or "order" instance. Instead, a new instance 'basedOn' the prior instance should be created with the new 'intent' value.

One exception to this is that the granularity of CommunicationRequest.intent is allowed to change. For example, a Request identified as an "order" might later be clarified to be a "filler-order". Or, in rarer cases (to meet recipient constraints), the reverse might also occur.

Codes indicating the degree of authority/intentionality associated with a request.

Proposals/recommendations, plans and orders all use the same structure and can exist in the same fulfillment chain.

The type of message to be sent such as alert, notification, reminder, instruction, etc.

There may be multiple axes of categorization and one communication request may serve multiple purposes.

Codes for general categories of communications such as alerts, instruction, etc.

Characterizes how quickly the proposed act must be initiated. Includes concepts such as stat, urgent, routine.

Codes indicating the relative importance of a communication request.

If true indicates that the CommunicationRequest is asking for the specified action to not occur.

The attributes provided with the request qualify what is not to be done.

A channel that was used for this communication (e.g. email, fax).

Codes for communication mediums such as phone, fax, email, in person, etc.

The patient or group that is the focus of this communication request.

Other resources that pertain to this communication request and to which this communication request should be associated.

Don't use CommunicationRequest.about element when a more specific element exists, such as basedOn, reasonReference, or replaces.

The Encounter during which this CommunicationRequest was created or to which the creation of this record is tightly associated.

This will typically be the encounter the event occurred within, but some activities may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter.

Text, attachment(s), or resource(s) to be communicated to the recipient.

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. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

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 in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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).

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.

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.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

Text, attachment(s), or resource(s) to be communicated to the recipient.

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. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

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 in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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).

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.

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.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

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. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

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.

BCP 13 (RFCs 2045, 2046, 2047, 4288, 4289 and 2049)

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.

IETF language tag for 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, base64 encoded.

The base64-encoded data SHALL be expressed in the same character set as the base resource XML or JSON.

The data needs to able to be transmitted inline.

A 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 number of bytes is redundant if the data is provided as a base64binary, but is useful if the data is provided as a url reference.

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 hash is calculated on the data prior to base64 encoding, if the data is based64 encoded. The hash is not intended to support digital signatures. Where protection against malicious threats a digital signature should be considered, see Provenance.signature for mechanism to protect a resource with a digital signature.

Included so that applications can verify that the contents of a location have not changed due to technical failures (e.g., storage rot, transport glitch, incorrect version).

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

May sometimes be derived from the source filename.

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.

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

Height of the image in pixels (photo/video).

Width of the image in pixels (photo/video).

The number of frames in a photo. This is used with a multi-page fax, or an imaging acquisition context that takes multiple slices in a single image, or an animated gif. If there is more than one frame, this SHALL have a value in order to alert interface software that a multi-frame capable rendering widget is required.

if the number of frames is not supplied, the value may be unknown. Applications should not assume that there is only one frame unless it is explicitly stated.

The duration of the recording in seconds - for audio and video.

The duration might differ from occurrencePeriod if recording was paused.

The number of pages when printed.

Text, attachment(s), or resource(s) to be communicated to the recipient.

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. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

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 in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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).

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.

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.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

The communicated content (or for multi-part communications, one portion of the communication).

The content can be codified or textual. As an example of codified content, when working with machine generated communications, the payload may be drawn from a finite, terminology defined set of communications, especially for short, status update kinds of communications where more of a natural language approach isn't appropriate.

If the content isn't codified, contentCodeableConcept.text can be used.

When using contentCodeableConcept, the CodeableConcept is what is being communicated and is not a categorization of the content.

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. To make the use of extensions safe and managable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

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.

BCP 13 (RFCs 2045, 2046, 2047, 4288, 4289 and 2049)

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.

IETF language tag for 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, base64 encoded.

The base64-encoded data SHALL be expressed in the same character set as the base resource XML or JSON.

The data needs to able to be transmitted inline.

A 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 number of bytes is redundant if the data is provided as a base64binary, but is useful if the data is provided as a url reference.

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 hash is calculated on the data prior to base64 encoding, if the data is based64 encoded. The hash is not intended to support digital signatures. Where protection against malicious threats a digital signature should be considered, see Provenance.signature for mechanism to protect a resource with a digital signature.

Included so that applications can verify that the contents of a location have not changed due to technical failures (e.g., storage rot, transport glitch, incorrect version).

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

May sometimes be derived from the source filename.

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.

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

Height of the image in pixels (photo/video).

Width of the image in pixels (photo/video).

The number of frames in a photo. This is used with a multi-page fax, or an imaging acquisition context that takes multiple slices in a single image, or an animated gif. If there is more than one frame, this SHALL have a value in order to alert interface software that a multi-frame capable rendering widget is required.

if the number of frames is not supplied, the value may be unknown. Applications should not assume that there is only one frame unless it is explicitly stated.

The duration of the recording in seconds - for audio and video.

The duration might differ from occurrencePeriod if recording was paused.

The number of pages when printed.

The time when this communication is to occur.

For draft requests, indicates the date of initial creation. For requests with other statuses, indicates the date of activation.

The device, individual, or organization who asks for the information to be shared.

The entity (e.g. person, organization, clinical information system, device, group, or care team) which is the intended target of the communication.

The entity (e.g. person, organization, clinical information system, or device) which is to be the source of the communication.

Describes why the request is being made in coded or textual form.

Textual reasons can be captured using reasonCode.text.

Codes for describing reasons for the occurrence of a communication.

Comments made about the request by the requester, sender, recipient, subject or other participants.