A record of a request for service such as diagnostic investigations, treatments, or operations to be performed.

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

DSTU2: DiagnosticOrder.supportingInformation additional types (Reference(http://hl7.org/fhir/StructureDefinition/Observation), Reference(http://hl7.org/fhir/StructureDefinition/Condition), Reference(http://hl7.org/fhir/StructureDefinition/DocumentReference))

Element DiagnosticOrder.supportingInformation is mapped to FHIR R5 element ServiceRequest.reason as RelatedTo. Element DiagnosticOrder.supportingInformation is mapped to FHIR R5 element ServiceRequest.supportingInfo as RelatedTo. The mappings for DiagnosticOrder.supportingInformation do not cover the following types: Reference. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". Examples include reporting the amount of inspired oxygen for blood gasses, the point in the menstrual cycle for cervical pap tests, and other conditions that influence test interpretations.

DSTU2: DiagnosticOrder.event (new:BackboneElement)

Element DiagnosticOrder.event has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.event has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element). This is not the same as an audit trail. It is a view of the important things that happened in the past. Typically, there would only be one entry for any given status, and systems may not record all the status events.

DSTU2: DiagnosticOrder.item.status (new:code)

Element DiagnosticOrder.item.status has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.item.status has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element). If the request has multiple items that have their own life cycles, then the items will have their own status while the overall diagnostic order is (usually) "in-progress".

DSTU2: DiagnosticOrder.item.event (new:DiagnosticOrder.event)

Element DiagnosticOrder.item.event has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.item.event has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element).

An Extension

DSTU2: DiagnosticOrder.status additional codes

Element DiagnosticOrder.status is mapped to FHIR R5 element ServiceRequest.status as RelatedTo. Element DiagnosticOrder.status is mapped to FHIR R5 element ServiceRequest.intent as RelatedTo. The mappings for DiagnosticOrder.status do not allow expression of the necessary codes, per the bindings on the source and target. Typically the system placing the order sets the status to "requested". Thereafter, the order is maintained by the receiver that updates the status as the request is handled.

The status of the order.

The status is generally fully in the control of the requester - they determine whether the order is draft or active and, after it has been activated, competed, revoked or placed on-hold. States relating to the activities of the performer are reflected on either the corresponding event (see Event Pattern for general discussion) or using the Task resource.

The status of a service order.

Whether the request is a proposal, plan, an original order or a reflex order.

This element is labeled as a modifier because the intent alters when and how the resource is actually applicable.

The kind of service request.

Set this to true if the record is saying that the service/procedure should NOT be performed.

In general, only the code and timeframe will be present, though occasional additional qualifiers such as body site or even performer could be included to narrow the scope of the prohibition. If the ServiceRequest.code and ServiceRequest.doNotPerform both contain negation, that will reinforce prohibition and should not have a double negative interpretation.

Used for do not ambulate, do not elevate head of bed, do not flush NG tube, do not take blood pressure on a certain arm, etc.

On whom or what the service is to be performed. This is usually a human patient, but can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans).

An Extension

DSTU2: DiagnosticOrder.subject

Element DiagnosticOrder.subject is mapped to FHIR R5 element ServiceRequest.subject as SourceIsBroaderThanTarget. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.subject with unmapped reference targets: Device, Group, Location, Patient.

A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

DSTU2: DiagnosticOrder.meta additional types (Meta) additional types from child elements (lastUpdated, profile, security, tag, versionId)

Element DiagnosticOrder.meta is mapped to FHIR R5 element ServiceRequest.meta as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.meta do not cover the following types: Meta. The mappings for DiagnosticOrder.meta do not cover the following types based on type expansion: lastUpdated, profile, security, tag, versionId.

DSTU2: DiagnosticOrder.text additional types (Narrative) additional types from child elements (div, status)

Element DiagnosticOrder.text is mapped to FHIR R5 element ServiceRequest.text as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.text do not cover the following types: Narrative. The mappings for DiagnosticOrder.text do not cover the following types based on type expansion: div, status. Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative.

DSTU2: DiagnosticOrder.supportingInformation additional types (Reference(http://hl7.org/fhir/StructureDefinition/Observation), Reference(http://hl7.org/fhir/StructureDefinition/Condition), Reference(http://hl7.org/fhir/StructureDefinition/DocumentReference))

Element DiagnosticOrder.supportingInformation is mapped to FHIR R5 element ServiceRequest.reason as RelatedTo. Element DiagnosticOrder.supportingInformation is mapped to FHIR R5 element ServiceRequest.supportingInfo as RelatedTo. The mappings for DiagnosticOrder.supportingInformation do not cover the following types: Reference. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". Examples include reporting the amount of inspired oxygen for blood gasses, the point in the menstrual cycle for cervical pap tests, and other conditions that influence test interpretations.

DSTU2: DiagnosticOrder.event (new:BackboneElement)

Element DiagnosticOrder.event has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.event has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element). This is not the same as an audit trail. It is a view of the important things that happened in the past. Typically, there would only be one entry for any given status, and systems may not record all the status events.

DSTU2: DiagnosticOrder.item.status (new:code)

Element DiagnosticOrder.item.status has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.item.status has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element). If the request has multiple items that have their own life cycles, then the items will have their own status while the overall diagnostic order is (usually) "in-progress".

DSTU2: DiagnosticOrder.item.event (new:DiagnosticOrder.event)

Element DiagnosticOrder.item.event has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.item.event has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element).

DSTU2: DiagnosticOrder.status additional codes

Element DiagnosticOrder.status is mapped to FHIR R5 element ServiceRequest.status as RelatedTo. Element DiagnosticOrder.status is mapped to FHIR R5 element ServiceRequest.intent as RelatedTo. The mappings for DiagnosticOrder.status do not allow expression of the necessary codes, per the bindings on the source and target. Typically the system placing the order sets the status to "requested". Thereafter, the order is maintained by the receiver that updates the status as the request is handled.

DSTU2: DiagnosticOrder.identifier additional types (Identifier) additional types from child elements (assigner, period, system, type, use, value)

Element DiagnosticOrder.identifier is mapped to FHIR R5 element ServiceRequest.identifier as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.identifier do not cover the following types: Identifier. The mappings for DiagnosticOrder.identifier do not cover the following types based on type expansion: assigner, period, system, type, use, value. The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the notes section below.

DSTU2: DiagnosticOrder.subject

Element DiagnosticOrder.subject is mapped to FHIR R5 element ServiceRequest.subject as SourceIsBroaderThanTarget. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.subject with unmapped reference targets: Device, Group, Location, Patient.

DSTU2: DiagnosticOrder.encounter additional types from child elements (display, reference)

Element DiagnosticOrder.encounter is mapped to FHIR R5 element ServiceRequest.encounter as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.encounter do not cover the following types based on type expansion: display, reference. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.encounter with unmapped reference targets: Encounter.

DSTU2: DiagnosticOrder.orderer additional types from child elements (display, reference)

Element DiagnosticOrder.orderer is mapped to FHIR R5 element ServiceRequest.requester as RelatedTo. The mappings for DiagnosticOrder.orderer do not cover the following types based on type expansion: display, reference. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.orderer with unmapped reference targets: Practitioner.

DSTU2: DiagnosticOrder.specimen additional types from child elements (display, reference)

Element DiagnosticOrder.specimen is mapped to FHIR R5 element ServiceRequest.specimen as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.specimen do not cover the following types based on type expansion: display, reference. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.specimen with unmapped reference targets: Specimen. Many investigation requests will create a need for specimens, but the request itself is not actually about the specimens. This is provided for when the diagnostic investigation is requested on already existing specimens.

DSTU2: DiagnosticOrder.item.specimen additional types from child elements (display, reference)

Element DiagnosticOrder.item.specimen is mapped to FHIR R5 element ServiceRequest.specimen as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.item.specimen do not cover the following types based on type expansion: display, reference. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.item.specimen with unmapped reference targets: Specimen. A single specimen should not appear in both DiagnosticOrder.specimen and DiagnosticOrder.item.specimen.

DSTU2: DiagnosticOrder.note additional types (Annotation) additional types from child elements (author[x], text, time)

Element DiagnosticOrder.note is mapped to FHIR R5 element ServiceRequest.note as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.note do not cover the following types: Annotation. The mappings for DiagnosticOrder.note do not cover the following types based on type expansion: author[x], text, time.

A record of a request for service such as diagnostic investigations, treatments, or operations to be performed.

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.

An Extension

DSTU2: DiagnosticOrder.meta additional types (Meta) additional types from child elements (lastUpdated, profile, security, tag, versionId)

Element DiagnosticOrder.meta is mapped to FHIR R5 element ServiceRequest.meta as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.meta do not cover the following types: Meta. The mappings for DiagnosticOrder.meta do not cover the following types based on type expansion: lastUpdated, profile, security, tag, versionId.

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.

Unless not suitable, these codes SHALL be taken from AllSecurityLabels
(extensible to http://hl7.org/fhir/ValueSet/security-labels|5.0.0)

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.

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

An Extension

DSTU2: DiagnosticOrder.text additional types (Narrative) additional types from child elements (div, status)

Element DiagnosticOrder.text is mapped to FHIR R5 element ServiceRequest.text as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.text do not cover the following types: Narrative. The mappings for DiagnosticOrder.text do not cover the following types based on type expansion: div, status. Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative.

The status of the narrative - whether it's entirely generated (from just the defined data or the extensions too), or whether a human authored it and it may contain additional data.

The status of a resource narrative.

The actual narrative content, a stripped down version of XHTML.

The contents of the html element are an XHTML fragment containing only the basic html formatting elements described in chapters 7-11 and 15 of the HTML 4.0 standard, <a> elements (either name or href), images and internally contained stylesheets. The XHTML content SHALL NOT contain a head, a body, external stylesheet references, scripts, forms, base/link/xlink, frames, iframes and objects.

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

DSTU2: DiagnosticOrder.supportingInformation additional types (Reference(http://hl7.org/fhir/StructureDefinition/Observation), Reference(http://hl7.org/fhir/StructureDefinition/Condition), Reference(http://hl7.org/fhir/StructureDefinition/DocumentReference))

Element DiagnosticOrder.supportingInformation is mapped to FHIR R5 element ServiceRequest.reason as RelatedTo. Element DiagnosticOrder.supportingInformation is mapped to FHIR R5 element ServiceRequest.supportingInfo as RelatedTo. The mappings for DiagnosticOrder.supportingInformation do not cover the following types: Reference. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". Examples include reporting the amount of inspired oxygen for blood gasses, the point in the menstrual cycle for cervical pap tests, and other conditions that influence test interpretations.

DSTU2: DiagnosticOrder.event (new:BackboneElement)

Element DiagnosticOrder.event has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.event has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element). This is not the same as an audit trail. It is a view of the important things that happened in the past. Typically, there would only be one entry for any given status, and systems may not record all the status events.

DSTU2: DiagnosticOrder.item.status (new:code)

Element DiagnosticOrder.item.status has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.item.status has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element). If the request has multiple items that have their own life cycles, then the items will have their own status while the overall diagnostic order is (usually) "in-progress".

DSTU2: DiagnosticOrder.item.event (new:DiagnosticOrder.event)

Element DiagnosticOrder.item.event has a context of ServiceRequest based on following the parent source element upwards and mapping to ServiceRequest. Element DiagnosticOrder.item.event has no mapping targets in FHIR R5. Typically, this is because the element has been added (is a new element).

An Extension

DSTU2: DiagnosticOrder.status additional codes

Element DiagnosticOrder.status is mapped to FHIR R5 element ServiceRequest.status as RelatedTo. Element DiagnosticOrder.status is mapped to FHIR R5 element ServiceRequest.intent as RelatedTo. The mappings for DiagnosticOrder.status do not allow expression of the necessary codes, per the bindings on the source and target. Typically the system placing the order sets the status to "requested". Thereafter, the order is maintained by the receiver that updates the status as the request is handled.

Identifiers assigned to this order instance by the orderer and/or the receiver and/or order fulfiller.

The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 V2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 V2). For further discussion and examples see the resource notes section below.

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

An Extension

DSTU2: DiagnosticOrder.identifier additional types (Identifier) additional types from child elements (assigner, period, system, type, use, value)

Element DiagnosticOrder.identifier is mapped to FHIR R5 element ServiceRequest.identifier as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.identifier do not cover the following types: Identifier. The mappings for DiagnosticOrder.identifier do not cover the following types based on type expansion: assigner, period, system, type, use, value. The identifier.type element is used to distinguish between the identifiers assigned by the orderer (known as the 'Placer' in HL7 v2) and the producer of the observations in response to the order (known as the 'Filler' in HL7 v2). For further discussion and examples see the notes section below.

The purpose of this identifier.

Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.

Identifies the purpose for this identifier, if known .

Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.

A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.

This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.

A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.

Allows users to make use of identifiers when the identifier system is not known.

Establishes the namespace for the value - that is, an absolute URL that describes a set values that are unique.

Identifier.system is always case sensitive.

There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.

The portion of the identifier typically relevant to the user and which is unique within the context of the system.

If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the http://hl7.org/fhir/StructureDefinition/rendered-value). Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.

Time period during which identifier is/was valid for use.

Organization that issued/manages the identifier.

The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.

The URL pointing to a FHIR-defined protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest.

The PlanDefinition resource is used to describe series, sequences, or groups of actions to be taken, while the ActivityDefinition resource is used to define each specific step or activity to be performed. More information can be found in the Boundaries and Relationships section for PlanDefinition.

The URL pointing to an externally maintained protocol, guideline, orderset or other definition that is adhered to in whole or in part by this ServiceRequest.

This might be an HTML page, PDF, etc. or could just be a non-resolvable URI identifier.

Plan/proposal/order fulfilled by this request.

The request takes the place of the referenced completed or terminated request(s).

A shared identifier common to all service requests that were authorized more or less simultaneously by a single author, representing the composite or group identifier.

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.

Some business processes need to know if multiple items were ordered as part of the same "requisition" for billing or other purposes.

The status of the order.

The status is generally fully in the control of the requester - they determine whether the order is draft or active and, after it has been activated, competed, revoked or placed on-hold. States relating to the activities of the performer are reflected on either the corresponding event (see Event Pattern for general discussion) or using the Task resource.

The status of a service order.

Whether the request is a proposal, plan, an original order or a reflex order.

This element is labeled as a modifier because the intent alters when and how the resource is actually applicable.

The kind of service request.

A code that classifies the service for searching, sorting and display purposes (e.g. "Surgical Procedure").

There may be multiple axis of categorization depending on the context or use case for retrieving or displaying the resource. The level of granularity is defined by the category concepts in the value set.

Classification of the requested service.

Used for filtering what service request are retrieved and displayed.

Indicates how quickly the ServiceRequest should be addressed with respect to other requests.

Identifies the level of importance to be assigned to actioning the request.

Set this to true if the record is saying that the service/procedure should NOT be performed.

In general, only the code and timeframe will be present, though occasional additional qualifiers such as body site or even performer could be included to narrow the scope of the prohibition. If the ServiceRequest.code and ServiceRequest.doNotPerform both contain negation, that will reinforce prohibition and should not have a double negative interpretation.

Used for do not ambulate, do not elevate head of bed, do not flush NG tube, do not take blood pressure on a certain arm, etc.

A code or reference that identifies a particular service (i.e., procedure, diagnostic investigation, or panel of investigations) that have been requested.

Many laboratory and radiology procedure codes embed the specimen/organ system in the test order name, for example, serum or serum/plasma glucose, or a chest x-ray. The specimen might not be recorded separately from the test code.

​Codes for tests or services that can be carried out by a designated individual, organization or healthcare service. For laboratory, LOINC is preferred and a valueset using LOINC Order codes is available here.

Additional details and instructions about the how the services are to be delivered. For example, and order for a urinary catheter may have an order detail for an external or indwelling catheter, or an order for a bandage may require additional instructions specifying how the bandage should be applied.

For information from the medical record intended to support the delivery of the requested services, use the supportingInformation element.

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.

Indicates the context of the order details by reference.

The parameter details for the service being requested.

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.

A value representing the additional detail or instructions for the order (e.g., catheter insertion, body elevation, descriptive device configuration and/or setting instructions).

Codes for order detail parameters.

Indicates a value for the order detail.

CodeableConcept values are indented to express concepts that would normally be coded - when a code is not available for a concept, CodeableConcept.text can be used. When the data is a text or not a single identifiable concept, string should be used.

An amount of service being requested which can be a quantity ( for example $1,500 home modification), a ratio ( for example, 20 half day visits per month), or a range (2.0 to 1.8 Gy per fraction).

When ordering a service the number of service items may need to be specified separately from the the service item.

On whom or what the service is to be performed. This is usually a human patient, but can also be requested on animals, groups of humans or animals, devices such as dialysis machines, or even locations (typically for environmental scans).

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

An Extension

DSTU2: DiagnosticOrder.subject

Element DiagnosticOrder.subject is mapped to FHIR R5 element ServiceRequest.subject as SourceIsBroaderThanTarget. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.subject with unmapped reference targets: Device, Group, Location, Patient.

A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a known RESTful URL) or by resolving the target of the reference.

Unless not suitable, these codes SHALL be taken from ResourceType
(extensible to http://hl7.org/fhir/ValueSet/resource-types|5.0.0)

Aa resource (or, for logical models, the URI of the logical model).

An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

This element only allows for a single identifier. In the case where additional identifers are required, use the http://hl7.org/fhir/StructureDefinition/additionalIdentifier extension.

Plain text narrative that identifies the resource in addition to the resource reference.

This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

The actual focus of a service request when it is not the subject of record representing something or someone associated with the subject such as a spouse, parent, fetus, or donor. The focus of a service request could also be an existing condition, an intervention, the subject's diet, another service request on the subject, or a body structure such as tumor or implanted device.

An encounter that provides additional information about the healthcare context in which this request is made.

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

An Extension

DSTU2: DiagnosticOrder.encounter additional types from child elements (display, reference)

Element DiagnosticOrder.encounter is mapped to FHIR R5 element ServiceRequest.encounter as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.encounter do not cover the following types based on type expansion: display, reference. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.encounter with unmapped reference targets: Encounter.

A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a known RESTful URL) or by resolving the target of the reference.

Unless not suitable, these codes SHALL be taken from ResourceType
(extensible to http://hl7.org/fhir/ValueSet/resource-types|5.0.0)

Aa resource (or, for logical models, the URI of the logical model).

An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

This element only allows for a single identifier. In the case where additional identifers are required, use the http://hl7.org/fhir/StructureDefinition/additionalIdentifier extension.

Plain text narrative that identifies the resource in addition to the resource reference.

This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

The date/time at which the requested service should occur.

If a CodeableConcept is present, it indicates the pre-condition for performing the service. For example "pain", "on flare-up", etc.

A coded concept identifying the pre-condition that should hold prior to performing a procedure. For example "pain", "on flare-up", etc.

When the request transitioned to being actionable.

The individual who initiated the request and has responsibility for its activation.

This not the dispatcher, but rather who is the authorizer. This element is not intended to handle delegation which would generally be managed through the Provenance resource.

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

An Extension

DSTU2: DiagnosticOrder.orderer additional types from child elements (display, reference)

Element DiagnosticOrder.orderer is mapped to FHIR R5 element ServiceRequest.requester as RelatedTo. The mappings for DiagnosticOrder.orderer do not cover the following types based on type expansion: display, reference. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.orderer with unmapped reference targets: Practitioner.

A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a known RESTful URL) or by resolving the target of the reference.

Unless not suitable, these codes SHALL be taken from ResourceType
(extensible to http://hl7.org/fhir/ValueSet/resource-types|5.0.0)

Aa resource (or, for logical models, the URI of the logical model).

An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

This element only allows for a single identifier. In the case where additional identifers are required, use the http://hl7.org/fhir/StructureDefinition/additionalIdentifier extension.

Plain text narrative that identifies the resource in addition to the resource reference.

This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

Desired type of performer for doing the requested service.

This is a role, not a participation type. In other words, does not describe the task but describes the capacity. For example, “compounding pharmacy”, “psychiatrist” or “internal referral”.

Indicates specific responsibility of an individual within the care team, such as "Primary physician", "Team coordinator", "Caregiver", etc.

The desired performer for doing the requested service. For example, the surgeon, dermatopathologist, endoscopist, etc.

If multiple performers are present, it is interpreted as a list of alternative performers without any preference regardless of order. If order of preference is needed use the http://hl7.org/fhir/StructureDefinition/request-performerOrder. Use CareTeam to represent a group of performers (for example, Practitioner A and Practitioner B).

The preferred location(s) where the procedure should actually happen in coded or free text form. E.g. at home or nursing day care center.

A location type where services are delivered.

An explanation or justification for why this service is being requested in coded or textual form. This is often for billing purposes. May relate to the resources referred to in supportingInfo.

This element represents why the referral is being made and may be used to decide how the service will be performed, or even if it will be performed at all. To be as specific as possible, a reference to Observation or Condition should be used if available. Otherwise, use concept.text element if the data is free (uncoded) text as shown in the CT Scan example.

SNOMED CT Condition/Problem/Diagnosis Codes

Insurance plans, coverage extensions, pre-authorizations and/or pre-determinations that may be needed for delivering the requested service.

Additional clinical information about the patient or specimen that may influence the services or their interpretations. This information includes diagnosis, clinical findings and other observations. In laboratory ordering these are typically referred to as "ask at order entry questions (AOEs)". This includes observations explicitly requested by the producer (filler) to provide context or supporting information needed to complete the order. For example, reporting the amount of inspired oxygen for blood gas measurements.

To represent information about how the services are to be delivered use the instructions element.

One or more specimens that the laboratory procedure will use.

The purpose of the ServiceRequest.specimen is to reflect the actual specimen that the requested test/procedure is asked to be performed on, whether the lab already has it or not. References to specimens for purposes other than to perform a test/procedure on should be made using the ServiceRequest.supportingInfo or the Specimen.parent where the Specimen.parent would enable descendency and ServiceRequest.supportingInfo a general reference for context.

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

An Extension

DSTU2: DiagnosticOrder.specimen additional types from child elements (display, reference)

Element DiagnosticOrder.specimen is mapped to FHIR R5 element ServiceRequest.specimen as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.specimen do not cover the following types based on type expansion: display, reference. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.specimen with unmapped reference targets: Specimen. Many investigation requests will create a need for specimens, but the request itself is not actually about the specimens. This is provided for when the diagnostic investigation is requested on already existing specimens.

DSTU2: DiagnosticOrder.item.specimen additional types from child elements (display, reference)

Element DiagnosticOrder.item.specimen is mapped to FHIR R5 element ServiceRequest.specimen as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.item.specimen do not cover the following types based on type expansion: display, reference. The standard extension alternate-reference has been mapped as the representation of FHIR DSTU2 element DiagnosticOrder.item.specimen with unmapped reference targets: Specimen. A single specimen should not appear in both DiagnosticOrder.specimen and DiagnosticOrder.item.specimen.

A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a known RESTful URL) or by resolving the target of the reference.

Unless not suitable, these codes SHALL be taken from ResourceType
(extensible to http://hl7.org/fhir/ValueSet/resource-types|5.0.0)

Aa resource (or, for logical models, the URI of the logical model).

An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

This element only allows for a single identifier. In the case where additional identifers are required, use the http://hl7.org/fhir/StructureDefinition/additionalIdentifier extension.

Plain text narrative that identifies the resource in addition to the resource reference.

This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

Anatomic location where the procedure should be performed. This is the target site.

Only used if not implicit in the code found in ServiceRequest.code. If the use case requires BodySite to be handled as a separate resource instead of an inline coded element (e.g. to identify and track separately) then use the standard extension http://hl7.org/fhir/StructureDefinition/procedure-targetBodyStructure.

SNOMED CT Body site concepts

Knowing where the procedure is performed is important for tracking if multiple sites are possible.

Anatomic location where the procedure should be performed. This is the target site.

Knowing where the procedure is performed is important for tracking if multiple sites are possible.

Any other notes and comments made about the service request. For example, internal billing notes.

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

An Extension

DSTU2: DiagnosticOrder.note additional types (Annotation) additional types from child elements (author[x], text, time)

Element DiagnosticOrder.note is mapped to FHIR R5 element ServiceRequest.note as SourceIsBroaderThanTarget. The mappings for DiagnosticOrder.note do not cover the following types: Annotation. The mappings for DiagnosticOrder.note do not cover the following types based on type expansion: author[x], text, time.

The individual responsible for making the annotation.

Organization is used when there's no need for specific attribution as to who made the comment.

Indicates when this particular annotation was made.

The text of the annotation in markdown format.