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2.7 Resource List - Content

FHIR Infrastructure icon Work GroupMaturity Level: 4 Trial UseSecurity Category: Not Classified Compartments: Device, Patient, Practitioner

A List is a curated collection of resources, for things such as problem lists, allergy lists, facility list, organization list, etc.

The List resource is a flat, possibly ordered collection of records. List resources are used in many places, including allergies, medications, alerts, family history, medical history, etc. List resources can be used to support patient-specific clinical lists as well as lists that manage workflows such as tracking patients, managing teaching cases, etc. Resources supported by the List resource can be homogeneous – consisting of only one type of resource (e.g. allergy lists) as well as heterogeneous – containing a variety of resources (e.g. a problem list including Conditions, AllergyIntolerances, recent Procedures, etc.). A list cannot be the subject of an intervention or a direct action.

Lists will typically include references to the resources that make up the list, however in some cases the details of the content of the list might be expressed in narrative only; e.g. a text record of a family history. The List resource is only needed if there is a need to filter the set of resources by a mechanism that cannot be accomplished via a simple query; e.g. there is no need to have a list for all AllergyIntolerances that exist on a server for a given patient. However, List is an appropriate mechanism to provide a filtered list of the subset of AllergyIntolerances that are deemed to be "current". Lists are allowed to contain other Lists, to create a nested collection of Lists.

Querying a List of resources such as AllergyIntolerance, Condition or Medication-related resources is different than querying the resource-specific endpoint. For example, a List of AllergyIntolerance resources would represent a curated point-in-time snapshot of the patient's allergies and intolerances. On the other hand, querying the AllergyIntolerance endpoint would typically produce a larger set of records as it would both be non-curated (potentially containing duplicate or out-of-date records) and current - generated based on information as of "now" rather than the last time a human manually revised the List resource instance. Which mechanism is most appropriate for data retrieval will vary by use-case. In some cases, systems might not have an appropriate curated List to query.

Note that the presence of an item in a List resource SHALL NOT change the meaning of any information that would be understood by looking at the item outside the context of the List, because items may be accessed directly outside the List by RESTful means or after a document is processed. For example, a List with a code that means "refuted conditions" cannot have items that are Condition resources that do not have a verificationStatus of refuted.

There are five mechanisms in FHIR for communicating collections of resources:

  • This List resource - enumerates a flat collection of resources and provides features for managing the collection. While a particular List instance may represent a "snapshot", from a business process perspective the notion of "List" is dynamic – items are added and removed over time. The List resource references other resources. Lists may be curated and have specific business meaning.
  • The Group resource - defines a group of specific people, animals, devices, etc. by enumerating them, or by describing qualities that group members have. The group resource refers to other resources, possibly implicitly. Groups are intended to be acted upon or observed as a whole; e.g. performing therapy on a group, calculating risk for a group, etc. This resource will commonly be used for public health (e.g. describing an at-risk population), clinical trials (e.g. defining a test subject pool) and similar purposes.
  • The Composition resource - defines a set of healthcare-related information that is assembled together into a single logical document that provides a single coherent statement of meaning, establishes its own context and that has clinical attestation with regard to who is making the statement. The Composition resource provides the basic structure of a FHIR document. The full content of the document is expressed using a bundle. Compositions will often reference Lists as the focus of particular sections.
  • The Bundle resource - is an infrastructure container for a group of resources. It does not have a narrative and is used to group collections of resources for transmission, persistence or processing (e.g. messages, documents, transactions, query responses, etc.) The content of bundles is typically algorithmically determined for a particular exchange or persistence purpose.
  • The DomainResource.contained element - allows multiple resources to be nested inside any DomainResource. This is a special type of grouping where the grouped resources lose independent existence - they no longer have their own identifiers, can't easily be queried independently, etc. Use of this grouping is a technical mechanism for managing the independence of resources and has no impact on meaning. Contained, bundled, and remotely referenced resources convey the same meaning.

Structure

NameFlagsCard.TypeDescription & Constraintsdoco
.. List TU DomainResource A list is a curated collection of resources
+ Rule: A list can only have an emptyReason if it is empty

Elements defined in Ancestors: id, meta, implicitRules, language, text, contained, extension, modifierExtension
... identifier 0..* Identifier Business identifier

... status ?!Σ 1..1 code current | retired | entered-in-error
Binding: List Status (Required)
... mode ?!Σ 1..1 code working | snapshot | changes
Binding: List Mode (Required)
... code Σ 0..1 CodeableConcept What the purpose of this list is
Binding: Example Use Codes for List (Example)
... subject Σ 0..* Reference(Any) If all resources have the same subject(s)

... encounter 0..1 Reference(Encounter) Context in which list created
... date Σ 0..1 dateTime When the list was prepared
... source Σ 0..1 Reference(Practitioner | PractitionerRole | Patient | Device | Organization | RelatedPerson | CareTeam) Who and/or what defined the list contents (aka Author)
... orderedBy 0..1 CodeableConcept What order the list has
Binding: List Order Codes (Preferred)
... note 0..* Annotation Comments about the list

... entry C 0..* BackboneElement Entries in the list
This repeating element order: Order has no meaning unless specifically asserted by List.orderedBy, in which case the List SHALL be interpreted as being ordered as specified by List.orderedBy.
.... flag 0..1 CodeableConcept Status/Workflow information about this item
Binding: Patient Medicine Change Types (Example)
.... deleted ?! 0..1 boolean If this item is actually marked as deleted
.... date 0..1 dateTime When item added to list
.... item 1..1 Reference(Any) Actual entry
... emptyReason C 0..1 CodeableConcept Why list is empty
Binding: List Empty Reasons (Preferred)

doco Documentation for this format icon

See the Extensions for this resource

UML Diagram (Legend)

List (DomainResource)Identifier for the List assigned for business purposes outside the context of FHIRidentifier : Identifier [0..*]Indicates the current state of this list (this element modifies the meaning of other elements)status : code [1..1] « null (Strength=Required)ListStatus! »How this list was prepared - whether it is a working list that is suitable for being maintained on an ongoing basis, or if it represents a snapshot of a list of items from another source, or whether it is a prepared list where items may be marked as added, modified or deleted (this element modifies the meaning of other elements)mode : code [1..1] « null (Strength=Required)ListMode! »A label for the list assigned by the authortitle : string [0..1]This code defines the purpose of the list - why it was createdcode : CodeableConcept [0..1] « null (Strength=Example)ExampleUseCodesForList?? »The common subject(s) (or patient(s)) of the resources that are in the list if there is one (or a set of subjects)subject : Reference [0..*] « Any »The encounter that is the context in which this list was createdencounter : Reference [0..1] « Encounter »Date list was last reviewed/revised and determined to be 'current'date : dateTime [0..1]The entity responsible for deciding what the contents of the list were. Where the list was created by a human, this is the same as the author of the listsource : Reference [0..1] « Practitioner|PractitionerRole|Patient| Device|Organization|RelatedPerson|CareTeam »What order applies to the items in the listorderedBy : CodeableConcept [0..1] « null (Strength=Preferred)ListOrderCodes? »Comments that apply to the overall listnote : Annotation [0..*]If the list is empty, why the list is emptyemptyReason : CodeableConcept [0..1] « null (Strength=Preferred)ListEmptyReasons? » « This element has or is affected by some invariantsC »EntryThe flag allows the system constructing the list to indicate the role and significance of the item in the listflag : CodeableConcept [0..1] « null (Strength=Example)PatientMedicineChangeTypes?? »True if this item is marked as deleted in the list (this element modifies the meaning of other elements)deleted : boolean [0..1]When this item was added to the listdate : dateTime [0..1]A reference to the actual resource from which data was deriveditem : Reference [1..1] « Any »Entries in this listentry[0..*]

XML Template

<List xmlns="http://hl7.org/fhir"> doco
 <!-- from Resource: id, meta, implicitRules, and language -->
 <!-- from DomainResource: text, contained, extension, and modifierExtension -->
 <identifier><!-- 0..* Identifier Business identifier --></identifier>
 <status value="[code]"/><!-- 1..1 current | retired | entered-in-error -->
 <mode value="[code]"/><!-- 1..1 working | snapshot | changes -->
 <title value="[string]"/><!-- 0..1 Descriptive name for the list -->
 <code><!-- 0..1 CodeableConcept What the purpose of this list is --></code>
 <subject><!-- 0..* Reference(Any) If all resources have the same subject(s) --></subject>
 <encounter><!-- 0..1 Reference(Encounter) Context in which list created --></encounter>
 <date value="[dateTime]"/><!-- 0..1 When the list was prepared -->
 <source><!-- 0..1 Reference(CareTeam|Device|Organization|Patient|Practitioner|
   PractitionerRole|RelatedPerson) Who and/or what defined the list contents (aka Author) --></source>
 <orderedBy><!-- 0..1 CodeableConcept What order the list has --></orderedBy>
 <note><!-- 0..* Annotation Comments about the list --></note>
 <entry>  <!-- I 0..* Entries in the list -->
  <flag><!-- 0..1 CodeableConcept Status/Workflow information about this item --></flag>
  <deleted value="[boolean]"/><!-- 0..1 If this item is actually marked as deleted -->
  <date value="[dateTime]"/><!-- 0..1 When item added to list -->
  <item><!-- 1..1 Reference(Any) Actual entry --></item>
 </entry>
 <emptyReason><!-- I 0..1 CodeableConcept Why list is empty --></emptyReason>
</List>

Turtle Template

@prefix fhir: <http://hl7.org/fhir/> .doco


[ a fhir:List;
  fhir:nodeRole fhir:treeRoot; # if this is the parser root

  # from Resource: .id, .meta, .implicitRules, and .language
  # from DomainResource: .text, .contained, .extension, and .modifierExtension
  fhir:identifier  ( [ Identifier ] ... ) ; # 0..* Business identifier
  fhir:status [ code ] ; # 1..1 current | retired | entered-in-error
  fhir:mode [ code ] ; # 1..1 working | snapshot | changes
  fhir:title [ string ] ; # 0..1 Descriptive name for the list
  fhir:code [ CodeableConcept ] ; # 0..1 What the purpose of this list is
  fhir:subject  ( [ Reference(Any) ] ... ) ; # 0..* If all resources have the same subject(s)
  fhir:encounter [ Reference(Encounter) ] ; # 0..1 Context in which list created
  fhir:date [ dateTime ] ; # 0..1 When the list was prepared
  fhir:source [ Reference(CareTeam|Device|Organization|Patient|Practitioner|PractitionerRole|RelatedPerson) ] ; # 0..1 Who and/or what defined the list contents (aka Author)
  fhir:orderedBy [ CodeableConcept ] ; # 0..1 What order the list has
  fhir:note  ( [ Annotation ] ... ) ; # 0..* Comments about the list
  fhir:entry ( [ # 0..* I Entries in the list
    fhir:flag [ CodeableConcept ] ; # 0..1 Status/Workflow information about this item
    fhir:deleted [ boolean ] ; # 0..1 If this item is actually marked as deleted
    fhir:date [ dateTime ] ; # 0..1 When item added to list
    fhir:item [ Reference(Any) ] ; # 1..1 Actual entry
  ] ... ) ;
  fhir:emptyReason [ CodeableConcept ] ; # 0..1 I Why list is empty
]

Changes from both R4 and R4B

List
List.subject
  • Max Cardinality changed from 1 to *
  • Type Reference: Added Target Type Resource
  • Type Reference: Removed Target Types Patient, Group, Device, Location
List.source
  • Type Reference: Added Target Types Organization, RelatedPerson, CareTeam

See the Full Difference for further information

This analysis is available for R4 as XML or JSON and for R4B as XML or JSON.

Structure

NameFlagsCard.TypeDescription & Constraintsdoco
.. List TU DomainResource A list is a curated collection of resources
+ Rule: A list can only have an emptyReason if it is empty

Elements defined in Ancestors: id, meta, implicitRules, language, text, contained, extension, modifierExtension
... identifier 0..* Identifier Business identifier

... status ?!Σ 1..1 code current | retired | entered-in-error
Binding: List Status (Required)
... mode ?!Σ 1..1 code working | snapshot | changes
Binding: List Mode (Required)
... code Σ 0..1 CodeableConcept What the purpose of this list is
Binding: Example Use Codes for List (Example)
... subject Σ 0..* Reference(Any) If all resources have the same subject(s)

... encounter 0..1 Reference(Encounter) Context in which list created
... date Σ 0..1 dateTime When the list was prepared
... source Σ 0..1 Reference(Practitioner | PractitionerRole | Patient | Device | Organization | RelatedPerson | CareTeam) Who and/or what defined the list contents (aka Author)
... orderedBy 0..1 CodeableConcept What order the list has
Binding: List Order Codes (Preferred)
... note 0..* Annotation Comments about the list

... entry C 0..* BackboneElement Entries in the list
This repeating element order: Order has no meaning unless specifically asserted by List.orderedBy, in which case the List SHALL be interpreted as being ordered as specified by List.orderedBy.
.... flag 0..1 CodeableConcept Status/Workflow information about this item
Binding: Patient Medicine Change Types (Example)
.... deleted ?! 0..1 boolean If this item is actually marked as deleted
.... date 0..1 dateTime When item added to list
.... item 1..1 Reference(Any) Actual entry
... emptyReason C 0..1 CodeableConcept Why list is empty
Binding: List Empty Reasons (Preferred)

doco Documentation for this format icon

See the Extensions for this resource

UML Diagram (Legend)

List (DomainResource)Identifier for the List assigned for business purposes outside the context of FHIRidentifier : Identifier [0..*]Indicates the current state of this list (this element modifies the meaning of other elements)status : code [1..1] « null (Strength=Required)ListStatus! »How this list was prepared - whether it is a working list that is suitable for being maintained on an ongoing basis, or if it represents a snapshot of a list of items from another source, or whether it is a prepared list where items may be marked as added, modified or deleted (this element modifies the meaning of other elements)mode : code [1..1] « null (Strength=Required)ListMode! »A label for the list assigned by the authortitle : string [0..1]This code defines the purpose of the list - why it was createdcode : CodeableConcept [0..1] « null (Strength=Example)ExampleUseCodesForList?? »The common subject(s) (or patient(s)) of the resources that are in the list if there is one (or a set of subjects)subject : Reference [0..*] « Any »The encounter that is the context in which this list was createdencounter : Reference [0..1] « Encounter »Date list was last reviewed/revised and determined to be 'current'date : dateTime [0..1]The entity responsible for deciding what the contents of the list were. Where the list was created by a human, this is the same as the author of the listsource : Reference [0..1] « Practitioner|PractitionerRole|Patient| Device|Organization|RelatedPerson|CareTeam »What order applies to the items in the listorderedBy : CodeableConcept [0..1] « null (Strength=Preferred)ListOrderCodes? »Comments that apply to the overall listnote : Annotation [0..*]If the list is empty, why the list is emptyemptyReason : CodeableConcept [0..1] « null (Strength=Preferred)ListEmptyReasons? » « This element has or is affected by some invariantsC »EntryThe flag allows the system constructing the list to indicate the role and significance of the item in the listflag : CodeableConcept [0..1] « null (Strength=Example)PatientMedicineChangeTypes?? »True if this item is marked as deleted in the list (this element modifies the meaning of other elements)deleted : boolean [0..1]When this item was added to the listdate : dateTime [0..1]A reference to the actual resource from which data was deriveditem : Reference [1..1] « Any »Entries in this listentry[0..*]

XML Template

<List xmlns="http://hl7.org/fhir"> doco
 <!-- from Resource: id, meta, implicitRules, and language -->
 <!-- from DomainResource: text, contained, extension, and modifierExtension -->
 <identifier><!-- 0..* Identifier Business identifier --></identifier>
 <status value="[code]"/><!-- 1..1 current | retired | entered-in-error -->
 <mode value="[code]"/><!-- 1..1 working | snapshot | changes -->
 <title value="[string]"/><!-- 0..1 Descriptive name for the list -->
 <code><!-- 0..1 CodeableConcept What the purpose of this list is --></code>
 <subject><!-- 0..* Reference(Any) If all resources have the same subject(s) --></subject>
 <encounter><!-- 0..1 Reference(Encounter) Context in which list created --></encounter>
 <date value="[dateTime]"/><!-- 0..1 When the list was prepared -->
 <source><!-- 0..1 Reference(CareTeam|Device|Organization|Patient|Practitioner|
   PractitionerRole|RelatedPerson) Who and/or what defined the list contents (aka Author) --></source>
 <orderedBy><!-- 0..1 CodeableConcept What order the list has --></orderedBy>
 <note><!-- 0..* Annotation Comments about the list --></note>
 <entry>  <!-- I 0..* Entries in the list -->
  <flag><!-- 0..1 CodeableConcept Status/Workflow information about this item --></flag>
  <deleted value="[boolean]"/><!-- 0..1 If this item is actually marked as deleted -->
  <date value="[dateTime]"/><!-- 0..1 When item added to list -->
  <item><!-- 1..1 Reference(Any) Actual entry --></item>
 </entry>
 <emptyReason><!-- I 0..1 CodeableConcept Why list is empty --></emptyReason>
</List>

Turtle Template

@prefix fhir: <http://hl7.org/fhir/> .doco


[ a fhir:List;
  fhir:nodeRole fhir:treeRoot; # if this is the parser root

  # from Resource: .id, .meta, .implicitRules, and .language
  # from DomainResource: .text, .contained, .extension, and .modifierExtension
  fhir:identifier  ( [ Identifier ] ... ) ; # 0..* Business identifier
  fhir:status [ code ] ; # 1..1 current | retired | entered-in-error
  fhir:mode [ code ] ; # 1..1 working | snapshot | changes
  fhir:title [ string ] ; # 0..1 Descriptive name for the list
  fhir:code [ CodeableConcept ] ; # 0..1 What the purpose of this list is
  fhir:subject  ( [ Reference(Any) ] ... ) ; # 0..* If all resources have the same subject(s)
  fhir:encounter [ Reference(Encounter) ] ; # 0..1 Context in which list created
  fhir:date [ dateTime ] ; # 0..1 When the list was prepared
  fhir:source [ Reference(CareTeam|Device|Organization|Patient|Practitioner|PractitionerRole|RelatedPerson) ] ; # 0..1 Who and/or what defined the list contents (aka Author)
  fhir:orderedBy [ CodeableConcept ] ; # 0..1 What order the list has
  fhir:note  ( [ Annotation ] ... ) ; # 0..* Comments about the list
  fhir:entry ( [ # 0..* I Entries in the list
    fhir:flag [ CodeableConcept ] ; # 0..1 Status/Workflow information about this item
    fhir:deleted [ boolean ] ; # 0..1 If this item is actually marked as deleted
    fhir:date [ dateTime ] ; # 0..1 When item added to list
    fhir:item [ Reference(Any) ] ; # 1..1 Actual entry
  ] ... ) ;
  fhir:emptyReason [ CodeableConcept ] ; # 0..1 I Why list is empty
]

Changes from both R4 and R4B

List
List.subject
  • Max Cardinality changed from 1 to *
  • Type Reference: Added Target Type Resource
  • Type Reference: Removed Target Types Patient, Group, Device, Location
List.source
  • Type Reference: Added Target Types Organization, RelatedPerson, CareTeam

See the Full Difference for further information

This analysis is available for R4 as XML or JSON and for R4B as XML or JSON.

 

Additional definitions: Master Definition XML + JSON, XML Schema/Schematron + JSON Schema, ShEx (for Turtle) + see the extensions, the spreadsheet version & the dependency analysis

Path ValueSet Type Documentation
List.status ListStatus Required

The current state of the list.

List.mode ListMode Required

The processing mode that applies to this list.

List.code ExampleUseCodesForList Example

Example use codes for the List resource - typical kinds of use.

List.orderedBy ListOrderCodes Preferred

Base values for the order of the items in a list resource.

List.entry.flag PatientMedicineChangeTypes Example

Example Item Flags for the List Resource. In this case, these are the kind of flags that would be used on a medication list at the end of a consultation.

List.emptyReason ListEmptyReasons Preferred

General reasons for a list to be empty. Reasons are either related to a summary list (i.e. problem or medication list) or to a workflow related list (i.e. consultation list).

UniqueKeyLevelLocationDescriptionExpression
img lst-1Rule (base)A list can only have an emptyReason if it is emptyemptyReason.empty() or entry.empty()

When a client system is interested in a patient's medications, allergies, problems, family history or other information typically handled via List, they have three options:

  • They can query for List instances of the appropriate type; or
  • They can query against the resource endpoint for the resources that make up the list (e.g. AllergyIntolerance, Condition MedicationStatement, etc.), possibly filtering by time, etc.
  • They can query against the resource endpoint, requesting one of the Current resource lists

Querying directly against the clinical resource endpoints will provide an un-curated view of information. A server may contain records that were part of various clinical documents, referrals and other submission sources that might not necessarily be considered wholly accurate or current, but which must be retained "as is" to provide a record of what data was received or seen by a clinician at a particular point in time.

On the other hand, lists are almost always curated. They will include only those records deemed by the author of the list to be both current and accurate. This can be both an advantage and a disadvantage. Lists are less likely to include irrelevant content, but there's a risk that they won't be completely up-to-date (new content may have been added that's more recent than when a given list was last updated). It's also possible that the list author's notion of "current" or "relevant" may differ from the perspective of the user performing the query. Also, there's the challenge that multiple lists may exist, with different author and different perspectives

The Current resource lists get around the problem of multiple lists and make it clear which list is considered authoritative, but not all systems will necessarily support this capability, and there's still the possibility that the list won't be completely up-to-date or will exclude information that is of interest to the querying system.

There's no right and wrong way to retrieve allergy, medication and other such information. Sometimes retrieving the "current" medication list will provide the best results, sometimes querying the raw records will provide better results. Sometimes providing the contents of the list plus a filtered view of the raw records may give the most useful information. Determining the most appropriate approach will depend on the needs of the user as well as the types of data sources for information held on the server and patterns of list maintenance. Client systems may well need to adapt their behavior in different environments if they can't count on consistent server behavior.

All lists are considered ordered - the order in which items literally appear in the list may be an important part of the meaning of the list. Reordering the items in a list may change the meaning of the list.

While a list always contains an ordered set of items, the significance of the order may be unknown, or it may be insignificant. As an example, consider a list of patients for a practitioner to visit. The list may be in the order in which the patients are to be visited, or it may be an unsorted list of patients to be visited in any order.

The List resource has an orderedBy element that, if present, specifies the meaning of the item order. Note, however, that the meaning of the order may be known implicitly rather than specified in the orderedBy element.

Applications SHOULD NOT reorder the elements in a list unless they understand the impact of this on the meaning of the list.

There are several different kinds of uses for a List resource:

working This list is the master list, maintained in an ongoing fashion with regular updates as the real-world list it is tracking changes.
snapshot This list was prepared as a snapshot. It should not be assumed to be current.
changes A point-in-time list that shows what changes have been made or recommended. E.g. a discharge medication list showing what was added and removed during an encounter.

The most common mode is "snapshot" - a list that is accurate within the context it is used in but not current or maintained after that; e.g., medications on discharge in a discharge summary. Note that these lists usually have a status of 'current' - they were current when they were prepared. Some kinds of lists may be explicitly retired (particularly if mode = working), but most will not be maintained after creation.

A change list may include deleted items. Some examples of change lists are a reconciled list of allergies, a discharge medication list and a list with new, updated and deleted items in it - though these might not be lists that include changes (this is an implementation decision). In order to ensure that the list is safe to process, any item where the flag implies that the item has actually been deleted SHALL have the deleted element set to true.

Note that there is no implication about the status of a resource that has been deleted. The only statement that is made is that the resource has been dropped from the list. However, applications should ensure that the implication of adding or deleting items from the list is consistent with the logical status of the resource and its contents.

A proper use of List.mode = "changes" with a deleted resource is in a medications list section of a discharge summary. See Example "med-list". An improper use would be if the list was a working list of patient medications in a clinical tracking system, and list item flags were used to implement version tracking history within the resource.

Some kinds of List resources may grow to a considerable size, and handling them may require more care than typical resources. Some approaches to consider include:

The narrative portion of the List resource should contain a summary of the items in the list, their key information, along with a human-readable summary of their flags (if present). The narrative may be generated from the data content and/or narrative of the resources referred to in the list, or it may be a narrative written by a human, which is partially or completely matched by structured data in the linked resources. The human written narrative may be the only content if the list has no entries (which would equate to a narrative only section in a document).

An HTML table is the recommended approach, though this is not required. Each List.item should appear in the narrative for the resource; i.e. it SHALL NOT be necessary to retrieve the list items in order to have a human-readable rendering of the content. In addition, if the List.text.status is "generated", then the narrative should not suggest the list contains items for which there are no corresponding List.item elements. If the list has flags, the representation should make clear use of visual hints (borders, lines, bullet marks, etc.) to ensure that human readers do not get confused about which flags belong with which item on space-poor displays (e.g. to prevent wrapping from separating the flags from the items).

Note that when a List resource is used in a Document, the narrative of the list is part of the attested content of the document.

In a dynamic environment, the narrative content of a list will be limited to the version of the linked resources at the time the list was last updated. It may be even earlier if the narrative isn't updated to reflect the most recent version of all referenced resources at each update. Best practice for 'working' lists is to update the narrative to reflect the most recent content of all list elements each time the list is revised. Lists should therefore not be relied on as a real-time view of the referenced content. There are a few possible approaches to work around this issue:

  • Provide minimal information about the listed resources, possibly limited to only a link. (Not recommended as this severely limits the usefulness of the narrative and is particularly problematic for things like documents where the only attested content might be the List narrative.)
  • Include only "generated" narrative, so the retriever can easily generate their own "current" view of the list by retrieving the referenced resources, ignoring the fixed narrative.
  • The server hosting the list can subscribe to all referenced resources and auto-update the narrative each time one of the referenced resources changes (or at least on a semi-frequent basis).

If a list is empty, there could be several different reasons why this is so. For example:

  • There are no appropriate entries for the list (i.e. the patient has no known medications/allergies/history)
  • The sender (human or system) deemed that these were not related to this context of patient care (usually for privacy related reasons)
  • The source system doesn't support these types of entries
  • The information to populate the list wasn't gathered - i.e. "Not asked"

Given these possibilities - especially the common and significant first case - for many kinds of lists, source systems SHOULD provide an empty reason if the list is empty. Because of the importance of the first case, the special value "nil-known" should be used when there are no (significant) entries in this context of care. Note that this concept is sometimes described differently, such as "patient denies taking medications", or "patient was unable to identify any relevant medical history".

When receiving a list, systems should not assume that the list is complete (some entries may have been withheld for a variety of reasons), unless there are specific trading partner arrangements in place or, if the list is empty, that there are actually nil known, unless the "nil-known" code is present.

If a list is empty, the narrative should contain text equivalent to the empty reason.

Note that there are also many kinds of lists that can be empty with no need for an empty reason (example)

The deleted flag must be used when using a list with mode = change when a resource is to be removed from the list. For working and snapshot lists, deleted items can either be flagged as deleted or outright removed from the list. An item MAY transition from the former to the latter after a particular period of time has passed). The choice of flagging vs. outright removal is determined by the list author.

Applications processsing list SHOULD always check the deleted flag.

Membership testing is used to test for active members of a List. Active entities in a list are entities:

  • listed in List.entry.item and
  • that do not have List.entry.deleted with a value of true.

Servers MAY impose additional membership constraints (e.g. based on modifier extensions).

Some known uses of list:

  • In XDS, as a submission set. See XDS profiles in MHD icon (there are several there)
  • For Medicine lists (see #1 icon, #2 icon)

This list is not comprehensive, but contributions are welcome.

Search parameters for this resource. See also the full list of search parameters for this resource, and check the Extensions registry for search parameters on extensions related to this resource. The common parameters also apply. See Searching for more information about searching in REST, messaging, and services.

Name Type Description Expression In Common
code token What the purpose of this list is List.code 21 Resources
date date When the list was prepared List.date 26 Resources
empty-reason token Why list is empty List.emptyReason
encounter reference Context in which list created List.encounter
(Encounter)
29 Resources
identifier token Business identifier List.identifier 65 Resources
item reference Actual entry List.entry.item
(Any)
notes string The annotation - text content (as markdown) List.note.text
patient reference If all resources have the same subject List.subject.where(resolve() is Patient)
(Patient)
65 Resources
source reference Who and/or what defined the list contents (aka Author) List.source
(Practitioner, Organization, CareTeam, Device, Patient, PractitionerRole, RelatedPerson)
status token current | retired | entered-in-error List.status
subject reference If all resources have the same subject List.subject
(Any)
title string Descriptive name for the list List.title