List

A list is a curated collection of resources.

Schema

Elements

Name	Required	Type	Description
identifier		Identifier[]	Business identifier Details Identifier for the List assigned for business purposes outside the context of FHIR.
status	✓	code	current | retired | entered-in-error Details Indicates the current state of this list. This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid.
mode	✓	code	working | snapshot | changes Details 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 is labeled as a modifier because a change list must not be misunderstood as a complete list.
title		string	Descriptive name for the list Details A label for the list assigned by the author.
code		CodeableConcept	What the purpose of this list is Details This code defines the purpose of the list - why it was created. If there is no code, the purpose of the list is implied where it is used, such as in a document section using Document.section.code.
subject		Reference< Patient | Group | Device | Location >	If all resources have the same subject Details The common subject (or patient) of the resources that are in the list if there is one. Some purely arbitrary lists do not have a common subject, so this is optional.
encounter		Reference<Encounter>	Context in which list created Details The encounter that is the context in which this list was created.
date		dateTime	When the list was prepared Details The date that the list was prepared. The actual important date is the date of currency of the resources that were summarized, but it is usually assumed that these are current when the preparation occurs.
source		Reference< Practitioner | PractitionerRole | Patient | Device >	Who and/or what defined the list contents (aka Author) Details 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 list. The primary source is the entity that made the decisions what items are in the list. This may be software or user.
orderedBy		CodeableConcept	What order the list has Details What order applies to the items in the list. Applications SHOULD render ordered lists in the order provided, but MAY allow users to re-order based on their own preferences as well. If there is no order specified, the order is unknown, though there may still be some order.
note		Annotation[]	Comments about the list Details Comments that apply to the overall list.
entry		ListEntry[]	Entries in the list Details Entries in this list. If there are no entries in the list, an emptyReason SHOULD be provided.
id		string	Unique id for inter-element referencing Details Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
extension		Extension[]	Additional content defined by implementations Details 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 manageable, 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.
modifierExtension		Extension[]	Extensions that cannot be ignored even if unrecognized Details 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 manageable, 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.
flag		CodeableConcept	Status/Workflow information about this item Details The flag allows the system constructing the list to indicate the role and significance of the item in the list. The flag can only be understood in the context of the List.code. If the flag means that the entry has actually been deleted from the list, the deleted element SHALL be true. Deleted can only be used if the List.mode is "changes".
deleted		boolean	If this item is actually marked as deleted Details True if this item is marked as deleted in the list. If the flag means that the entry has actually been deleted from the list, the deleted element SHALL be true. Both flag and deleted can only be used if the List.mode is "changes". A deleted entry should be displayed in narrative as deleted. This element is labeled as a modifier because it indicates that an item is (to be) no longer in the list.
date		dateTime	When item added to list Details When this item was added to the list.
item	✓	Reference<Resource>	Actual entry Details A reference to the actual resource from which data was derived.
emptyReason		CodeableConcept	Why list is empty Details If the list is empty, why the list is empty. The various reasons for an empty list make a significant interpretation to its interpretation. Note that this code is for use when the entire list has been suppressed, and not for when individual items are omitted - implementers may consider using a text note or a flag on an entry in these cases.

Search Parameters

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

Inherited Elements

Name	Required	Type	Description
id		string	Logical id of this artifact Details The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes. The only time that a resource does not have an id is when it is being submitted to the server using a create operation.
meta		Meta	Metadata about the resource Details 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.
implicitRules		uri	A set of rules under which this content was created Details 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 it's narrative along with other profiles, value sets, etc.
language		code	Language of the resource content Details 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).
text		Narrative	Text summary of the resource, for human interpretation Details 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 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.
contained		Resource[]	Contained, inline Resources Details These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope. This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again. Contained resources may have profiles and tags In their meta elements, but SHALL NOT have security labels.
extension		Extension[]	Additional content defined by implementations Details May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer 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.
modifierExtension		Extension[]	Extensions that cannot be ignored Details May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. 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.

Usage

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.).

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.

Relationships

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.

Referenced By

• MeasureReport