The CodeSystem resource is used to declare the existence of and describe a code system or code system supplement and its key properties, and optionally define a part or all of its content.

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.

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.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

The date (and optionally time) when the code system resource was created or revised.

Allows filtering of code systems that are appropriate for use versus not.

The lifecycle status of an artifact.

The extent of the content of the code system (the concepts and codes it defines) are represented in this resource instance.

The extent of the content of the code system (the concepts and codes it defines) are represented in a code system resource.

STU3: CodeSystem.meta additional types (Meta) additional types from child elements (lastUpdated, profile, security, tag, versionId)

Element CodeSystem.meta is mapped to FHIR R4B element CodeSystem.meta as SourceIsBroaderThanTarget. The mappings for CodeSystem.meta do not cover the following types: Meta. The mappings for CodeSystem.meta do not cover the following types based on type expansion: lastUpdated, profile, security, tag, versionId.

STU3: CodeSystem.text additional types (Narrative) additional types from child elements (div, status)

Element CodeSystem.text is mapped to FHIR R4B element CodeSystem.text as SourceIsBroaderThanTarget. The mappings for CodeSystem.text do not cover the following types: Narrative. The mappings for CodeSystem.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. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded in formation is added later.

STU3: CodeSystem.identifier additional types (Identifier) additional types from child elements (assigner, period, system, type, use, value)

Element CodeSystem.identifier is mapped to FHIR R4B element CodeSystem.identifier as RelatedTo. The mappings for CodeSystem.identifier do not cover the following types: Identifier. The mappings for CodeSystem.identifier do not cover the following types based on type expansion: assigner, period, system, type, use, value. Typically, this is used for identifiers that can go in an HL7 V3 II (instance identifier) data type, e.g., to identify this code system outside of FHIR, where it is not possible to use the logical URI.

STU3: CodeSystem.contact additional types (ContactDetail) additional types from child elements (name, telecom)

Element CodeSystem.contact is mapped to FHIR R4B element CodeSystem.contact as SourceIsBroaderThanTarget. The mappings for CodeSystem.contact do not cover the following types: ContactDetail. The mappings for CodeSystem.contact do not cover the following types based on type expansion: name, telecom. May be a web site, an email address, a telephone number, etc.

STU3: CodeSystem.useContext additional types (UsageContext) additional types from child elements (code, value[x])

Element CodeSystem.useContext is mapped to FHIR R4B element CodeSystem.useContext as SourceIsBroaderThanTarget. The mappings for CodeSystem.useContext do not cover the following types: UsageContext. The mappings for CodeSystem.useContext do not cover the following types based on type expansion: code, value[x]. When multiple useContexts are specified, there is no expectation whether all or any of the contexts apply.

The CodeSystem resource is used to declare the existence of and describe a code system or code system supplement and its key properties, and optionally define a part or all of its content.

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

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

The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content 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

STU3: CodeSystem.meta additional types (Meta) additional types from child elements (lastUpdated, profile, security, tag, versionId)

Element CodeSystem.meta is mapped to FHIR R4B element CodeSystem.meta as SourceIsBroaderThanTarget. The mappings for CodeSystem.meta do not cover the following types: Meta. The mappings for CodeSystem.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 value is always populated except when the resource is first being created. 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.

In the provenance resource, this corresponds to Provenance.entity.what[x]. The exact use of the source (and the implied Provenance.entity.role) is left to implementer discretion. Only one nominated source is allowed; for additional provenance details, a full Provenance resource should be used.

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.

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.

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.

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

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.

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

An Extension

STU3: CodeSystem.text additional types (Narrative) additional types from child elements (div, status)

Element CodeSystem.text is mapped to FHIR R4B element CodeSystem.text as SourceIsBroaderThanTarget. The mappings for CodeSystem.text do not cover the following types: Narrative. The mappings for CodeSystem.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. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded in formation is added later.

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 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, 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.

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.

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.

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.

An absolute URI that is used to identify this code system when it is referenced in a specification, model, design or an instance; also called its canonical identifier. This SHOULD be globally unique and SHOULD be a literal address at which at which an authoritative instance of this code system is (or will be) published. This URL can be the target of a canonical reference. It SHALL remain the same when the code system is stored on different servers. This is used in Coding.system.

Can be a urn:uuid: or a urn:oid: but real http: addresses are preferred. Multiple instances may share the same URL if they have a distinct version.

The determination of when to create a new version of a resource (same url, new version) vs. defining a new artifact is up to the author. Considerations for making this decision are found in Technical and Business Versions.

In some cases, the resource can no longer be found at the stated url, but the url itself cannot change. Implementations can use the meta.source element to indicate where the current master source of the resource can be found.

Allows the code system to be referenced by a single globally unique identifier.

A formal identifier that is used to identify this code system when it is represented in other formats, or referenced in a specification, model, design or an instance.

Typically, this is used for identifiers that can go in an HL7 V3 II (instance identifier) data type, and can then identify this code system outside of FHIR, where it is not possible to use the logical URI. Note that HL7 defines at least three identifiers for many of its code systems - the FHIR canonical URL, the OID and the V2 Table 0396 mnemonic code.

Allows externally provided and/or usable business identifiers to be easily associated with the module.

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

An Extension

STU3: CodeSystem.identifier additional types (Identifier) additional types from child elements (assigner, period, system, type, use, value)

Element CodeSystem.identifier is mapped to FHIR R4B element CodeSystem.identifier as RelatedTo. The mappings for CodeSystem.identifier do not cover the following types: Identifier. The mappings for CodeSystem.identifier do not cover the following types based on type expansion: assigner, period, system, type, use, value. Typically, this is used for identifiers that can go in an HL7 V3 II (instance identifier) data type, e.g., to identify this code system outside of FHIR, where it is not possible to use the logical URI.

The purpose of this identifier.

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

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.

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

Establishes the namespace for the value - that is, a 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 Rendered Value extension. 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 identifier that is used to identify this version of the code system when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the code system author and is not expected to be globally unique. For example, it might be a timestamp (e.g. yyyymmdd) if a managed version is not available. There is also no expectation that versions can be placed in a lexicographical sequence. This is used in Coding.version.

There may be different code system instances that have the same identifier but different versions. The version can be appended to the url in a reference to allow a reference to a particular business version of the code system with the format [url]|[version].

A natural language name identifying the code system. This name should be usable as an identifier for the module by machine processing applications such as code generation.

The name is not expected to be globally unique. The name should be a simple alphanumeric type name to ensure that it is machine-processing friendly.

Support human navigation and code generation.

A short, descriptive, user-friendly title for the code system.

This name does not need to be machine-processing friendly and may contain punctuation, white-space, etc.

The date (and optionally time) when the code system resource was created or revised.

Allows filtering of code systems that are appropriate for use versus not.

The lifecycle status of an artifact.

A Boolean value to indicate that this code system is authored for testing purposes (or education/evaluation/marketing) and is not intended to be used for genuine usage.

Allows filtering of code systems that are appropriate for use versus not.

Enables experimental content to be developed following the same lifecycle that would be used for a production-level code system.

The date (and optionally time) when the code system was published. The date must change when the business version changes and it must change if the status code changes. In addition, it should change when the substantive content of the code system changes.

Note that this is not the same as the resource last-modified-date, since the resource may be a secondary representation of the code system. Additional specific dates may be added as extensions or be found by consulting Provenances associated with past versions of the resource.

The name of the organization or individual that published the code system.

Usually an organization but may be an individual. The publisher (or steward) of the code system is the organization or individual primarily responsible for the maintenance and upkeep of the code system. This is not necessarily the same individual or organization that developed and initially authored the content. The publisher is the primary point of contact for questions or issues with the code system. This item SHOULD be populated unless the information is available from context.

Helps establish the "authority/credibility" of the code system. May also allow for contact.

Contact details to assist a user in finding and communicating with the publisher.

May be a web site, an email address, a telephone number, etc.

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

An Extension

STU3: CodeSystem.contact additional types (ContactDetail) additional types from child elements (name, telecom)

Element CodeSystem.contact is mapped to FHIR R4B element CodeSystem.contact as SourceIsBroaderThanTarget. The mappings for CodeSystem.contact do not cover the following types: ContactDetail. The mappings for CodeSystem.contact do not cover the following types based on type expansion: name, telecom. May be a web site, an email address, a telephone number, etc.

The name of an individual to contact.

If there is no named individual, the telecom information is for the organization as a whole.

The contact details for the individual (if a name was provided) or the organization.

A free text natural language description of the code system from a consumer's perspective.

This description can be used to capture details such as why the code system was built, comments about misuse, instructions for clinical use and interpretation, literature references, examples from the paper world, etc. It is not a rendering of the code system as conveyed in the 'text' field of the resource itself. This item SHOULD be populated unless the information is available from context (e.g. the language of the code system is presumed to be the predominant language in the place the code system was created).

The content was developed with a focus and intent of supporting the contexts that are listed. These contexts may be general categories (gender, age, ...) or may be references to specific programs (insurance plans, studies, ...) and may be used to assist with indexing and searching for appropriate code system instances.

When multiple useContexts are specified, there is no expectation that all or any of the contexts apply.

Assist in searching for appropriate content.

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

An Extension

STU3: CodeSystem.useContext additional types (UsageContext) additional types from child elements (code, value[x])

Element CodeSystem.useContext is mapped to FHIR R4B element CodeSystem.useContext as SourceIsBroaderThanTarget. The mappings for CodeSystem.useContext do not cover the following types: UsageContext. The mappings for CodeSystem.useContext do not cover the following types based on type expansion: code, value[x]. When multiple useContexts are specified, there is no expectation whether all or any of the contexts apply.

A code that identifies the type of context being specified by this usage context.

A value that defines the context specified in this context of use. The interpretation of the value is defined by the code.

A legal or geographic region in which the code system is intended to be used.

It may be possible for the code system to be used in jurisdictions other than those for which it was originally designed or intended.

Countries and regions within which this artifact is targeted for use.

Explanation of why this code system is needed and why it has been designed as it has.

This element does not describe the usage of the code system. Instead, it provides traceability of ''why'' the resource is either needed or ''why'' it is defined as it is. This may be used to point to source materials or specifications that drove the structure of this code system.

A copyright statement relating to the code system and/or its contents. Copyright statements are generally legal restrictions on the use and publishing of the code system.

... Sometimes, the copyright differs between the code system and the codes that are included. The copyright statement should clearly differentiate between these when required.

Consumers must be able to determine any legal restrictions on the use of the code system and/or its content.

If code comparison is case sensitive when codes within this system are compared to each other.

If this value is missing, then it is not specified whether a code system is case sensitive or not. When the rule is not known, Postel's law should be followed: produce codes with the correct case, and accept codes in any case. This element is primarily provided to support validation software.

Canonical reference to the value set that contains the entire code system.

The definition of the value set SHALL include all codes from this code system and only codes from this code system, and it SHALL be immutable.

The meaning of the hierarchy of concepts as represented in this resource.

Note that other representations might have a different hierarchy or none at all, and represent the information using properties.

The meaning of the hierarchy of concepts in a code system.

The code system defines a compositional (post-coordination) grammar.

Note that the code system resource does not define what the compositional grammar is, only whether or not there is one.

This flag is used to signify that the code system does not commit to concept permanence across versions. If true, a version must be specified when referencing this code system.

Best practice is that code systems do not redefine concepts, or that if concepts are redefined, a new code system definition is created. But this is not always possible, so some code systems may be defined as 'versionNeeded'.

Most code systems occasionally refine the displays defined for concepts between versions. Contexts in which the concept display values are validated may require that the version be specified for some code systems irrespective of the value of this property.

The extent of the content of the code system (the concepts and codes it defines) are represented in this resource instance.

The extent of the content of the code system (the concepts and codes it defines) are represented in a code system resource.

The canonical URL of the code system that this code system supplement is adding designations and properties to.

The most common use of a code system supplement is to add additional language support.

The total number of concepts defined by the code system. Where the code system has a compositional grammar, the basis of this count is defined by the system steward.

The count of concepts defined in this resource cannot be more than this value but may be less for several reasons - see the content element.

A filter that can be used in a value set compose statement when selecting concepts using a filter.

Note that filters defined in code systems usually require custom code on the part of any terminology engine that will make them available for use in value set filters. For this reason, they are generally only seen in high value published terminologies.

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 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.

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.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

The code that identifies this filter when it is used as a filter in ValueSet.compose.include.filter.

A description of how or why the filter is used.

A list of operators that can be used with the filter.

The kind of operation to perform as a part of a property based filter.

A description of what the value for the filter should be.

A property defines an additional slot through which additional information can be provided about a concept.

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 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.

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.

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 code that is used to identify the property. The code is used internally (in CodeSystem.concept.property.code) and also externally, such as in property filters.

Reference to the formal meaning of the property. One possible source of meaning is the Concept Properties code system.

A description of the property- why it is defined, and how its value might be used.

The type of the property value. Properties of type "code" contain a code defined by the code system (e.g. a reference to another defined concept).

The type of a property value.

Concepts that are in the code system. The concept definitions are inherently hierarchical, but the definitions must be consulted to determine what the meanings of the hierarchical relationships are.

If this is empty, it means that the code system resource does not represent the content of the code system.

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 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.

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.

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 code - a text symbol - that uniquely identifies the concept within the code system.

A human readable string that is the recommended default way to present this concept to a user.

The formal definition of the concept. The code system resource does not make formal definitions required, because of the prevalence of legacy systems. However, they are highly recommended, as without them there is no formal meaning associated with the concept.

Additional representations for the concept - other languages, aliases, specialized purposes, used for particular purposes, etc.

Concepts have both a display and an array of designation. The display is equivalent to a special designation with an implied designation.use of "primary code" and a language equal to the Resource Language.

Many concept definition systems support multiple representations, in multiple languages, and for multiple purposes.

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 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.

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.

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

The language this designation is defined for.

In the absence of a language, the resource language applies.

IETF language tag

A code that details how this designation would be used.

If no use is provided, the designation can be assumed to be suitable for general display to a human user.

Details of how a designation would be used.

The text value for this designation.

A property value for this concept.

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 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.

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.

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 code that is a reference to CodeSystem.property.code.

The value of this property.

Defines children of a concept to produce a hierarchy of concepts. The nature of the relationships is variable (is-a/contains/categorizes) - see hierarchyMeaning.