Generated Narrative: ConceptMap R5-AllergyIntolerance-element-map-to-R4 Mapping from http://hl7.org/fhir/5.0 to http://hl7.org/fhir/4.0 Group 1 Mapping from http://hl7.org/fhir/StructureDefinition/AllergyIntolerance|5.0.0 to AllergyIntoleranceversion: 4.0.1) Source Code Relationship Target Code Comment AllergyIntolerance.meta (meta) is equivalent to AllergyIntolerance.meta Element `AllergyIntolerance.meta` is mapped to FHIR R4 element `AllergyIntolerance.meta` as `Equivalent`. AllergyIntolerance.implicitRules (implicitRules) is equivalent to AllergyIntolerance.implicitRules Element `AllergyIntolerance.implicitRules` is mapped to FHIR R4 element `AllergyIntolerance.implicitRules` as `Equivalent`. Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of its narrative along with other profiles, value sets, etc. AllergyIntolerance.language (language) is equivalent to AllergyIntolerance.language Element `AllergyIntolerance.language` is mapped to FHIR R4 element `AllergyIntolerance.language` as `Equivalent`. 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). AllergyIntolerance.text (text) is equivalent to AllergyIntolerance.text Element `AllergyIntolerance.text` is mapped to FHIR R4 element `AllergyIntolerance.text` as `Equivalent`. Contained resources do not have a narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later. AllergyIntolerance.contained (contained) is equivalent to AllergyIntolerance.contained Element `AllergyIntolerance.contained` is mapped to FHIR R4 element `AllergyIntolerance.contained` as `Equivalent`. 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. AllergyIntolerance.identifier (identifier) is equivalent to AllergyIntolerance.identifier Element `AllergyIntolerance.identifier` is mapped to FHIR R4 element `AllergyIntolerance.identifier` as `Equivalent`. This is a business identifier, not a resource identifier (see [discussion](https://hl7.org/fhir/resource.htm#identifiers)). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number. AllergyIntolerance.clinicalStatus (clinicalStatus) is equivalent to AllergyIntolerance.clinicalStatus Element `AllergyIntolerance.clinicalStatus` is mapped to FHIR R4 element `AllergyIntolerance.clinicalStatus` as `Equivalent`. AllergyIntolerance.clinicalStatus should be present if verificationStatus is not entered-in-error and the AllergyIntolerance.code isn't negated (No Known Allergy, No Drug Allergy, No Food Allergy, No Latex Allergy). Refer to [discussion](https://hl7.org/fhir/extensibility.html#Special-Case) if clinicalStatus is missing data. The data type is CodeableConcept because clinicalStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity. AllergyIntolerance.verificationStatus (verificationStatus) maps to wider concept AllergyIntolerance.verificationStatus Element `AllergyIntolerance.verificationStatus` is mapped to FHIR R4 element `AllergyIntolerance.verificationStatus` as `SourceIsBroaderThanTarget`. The target context `AllergyIntolerance.verificationStatus` is a modifier element, so this extension does not need to be defined as a modifier. The data type is CodeableConcept because verificationStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity. AllergyIntolerance.type (type) maps to wider concept AllergyIntolerance.type Element `AllergyIntolerance.type` is mapped to FHIR R4 element `AllergyIntolerance.type` as `SourceIsBroaderThanTarget`. The mappings for `AllergyIntolerance.type` do not cover the following types: CodeableConcept. The mappings for `AllergyIntolerance.type` do not cover the following types based on type expansion: coding. Allergic (typically immune-mediated) reactions have been traditionally regarded as an indicator for potential escalation to significant future risk. Contemporary knowledge suggests that some reactions previously thought to be immune-mediated are, in fact, non-immune, but in some cases can still pose a life threatening risk. It is acknowledged that many clinicians might not be in a position to distinguish the mechanism of a particular reaction. Often the term "allergy" is used rather generically and may overlap with the use of "intolerance" - in practice the boundaries between these two concepts might not be well-defined or understood. This data element is included nevertheless, because many legacy systems have captured this attribute. Immunologic testing may provide supporting evidence for the basis of the reaction and the causative substance, but no tests are 100% sensitive or specific for sensitivity to a particular substance. If, as is commonly the case, it is unclear whether the reaction is due to an allergy or an intolerance, then the type element should be omitted from the resource. AllergyIntolerance.category (category) is equivalent to AllergyIntolerance.category Element `AllergyIntolerance.category` is mapped to FHIR R4 element `AllergyIntolerance.category` as `Equivalent`. This data element has been included because it is currently being captured in some clinical systems. This data can be derived from the substance where coding systems are used, and is effectively redundant in that situation. When searching on category, consider the implications of AllergyIntolerance resources without a category. For example, when searching on category = medication, medication allergies that don't have a category valued will not be returned. Refer to [search](https://hl7.org/fhir/search.html) for more information on how to search category with a :missing modifier to get allergies that don't have a category. Additionally, category should be used with caution because category can be subjective based on the sender. AllergyIntolerance.criticality (criticality) is equivalent to AllergyIntolerance.criticality Element `AllergyIntolerance.criticality` is mapped to FHIR R4 element `AllergyIntolerance.criticality` as `Equivalent`. The default criticality value for any propensity to an adverse reaction should be 'Low Risk', indicating at the very least a relative contraindication to deliberate or voluntary exposure to the substance. 'High Risk' is flagged if the clinician has identified a propensity for a more serious or potentially life-threatening reaction, such as anaphylaxis, and implies an absolute contraindication to deliberate or voluntary exposure to the substance. If this element is missing, the criticality is unknown (though it may be known elsewhere). Systems that capture a severity at the condition level are actually representing the concept of criticality whereas the severity documented at the reaction level is representing the true reaction severity. Existing systems that are capturing both condition criticality and reaction severity may use the term "severity" to represent both. Criticality is the worst it could be in the future (i.e. situation-agnostic) whereas severity is situation-dependent. AllergyIntolerance.code (code) is equivalent to AllergyIntolerance.code Element `AllergyIntolerance.code` is mapped to FHIR R4 element `AllergyIntolerance.code` as `Equivalent`. It is strongly recommended that this element be populated using a terminology, where possible. For example, some terminologies used include RxNorm, SNOMED CT, DM+D, NDFRT, ICD-9, IDC-10, UNII, and ATC. Plain text should only be used if there is no appropriate terminology available. Additional details can be specified in the text.#xD;#xD;When a substance or product code is specified for the 'code' element, the "default" semantic context is that this is a positive statement of an allergy or intolerance (depending on the value of the 'type' element, if present) condition to the specified substance/product. In the corresponding SNOMED CT allergy model, the specified substance/product is the target (destination) of the "Causative agent" relationship.#xD;#xD;The 'substanceExposureRisk' extension is available as a structured and more flexible alternative to the 'code' element for making positive or negative allergy or intolerance statements. This extension provides the capability to make "no known allergy" (or "no risk of adverse reaction") statements regarding any coded substance/product (including cases when a pre-coordinated "no allergy to x" concept for that substance/product does not exist). If the 'substanceExposureRisk' extension is present, the AllergyIntolerance.code element SHALL be omitted. AllergyIntolerance.patient (patient) is equivalent to AllergyIntolerance.patient Element `AllergyIntolerance.patient` is mapped to FHIR R4 element `AllergyIntolerance.patient` as `Equivalent`. AllergyIntolerance.encounter (encounter) is equivalent to AllergyIntolerance.encounter Element `AllergyIntolerance.encounter` is mapped to FHIR R4 element `AllergyIntolerance.encounter` as `Equivalent`. AllergyIntolerance.onset[x] (onset[x]) is equivalent to AllergyIntolerance.onset[x] Element `AllergyIntolerance.onset[x]` is mapped to FHIR R4 element `AllergyIntolerance.onset[x]` as `Equivalent`. The target context `AllergyIntolerance.onset[x]` is a choice-type element and cannot directly hold extensions. The context is moved up to parent element `AllergyIntolerance`. Age is generally used when the patient reports an age at which the AllergyIntolerance was noted. Period is generally used to convey an imprecise onset that occurred within the time period. Range is generally used to convey an imprecise age range (e.g. 4 to 6 years old). AllergyIntolerance.recordedDate (recordedDate) is equivalent to AllergyIntolerance.recordedDate Element `AllergyIntolerance.recordedDate` is mapped to FHIR R4 element `AllergyIntolerance.recordedDate` as `Equivalent`. When onset date is unknown, recordedDate can be used to establish if the allergy or intolerance was present on or before a given date. If the recordedDate is known and provided by a sending system, it is preferred that the receiving system preserve that recordedDate value. If the recordedDate is not provided by the sending system, the receipt timestamp is sometimes used as the recordedDate. AllergyIntolerance.lastOccurrence (lastOccurrence) is equivalent to AllergyIntolerance.lastOccurrence Element `AllergyIntolerance.lastOccurrence` is mapped to FHIR R4 element `AllergyIntolerance.lastOccurrence` as `Equivalent`. This date may be replicated by one of the Onset of Reaction dates. Where a textual representation of the date of last occurrence is required e.g. 'In Childhood, '10 years ago' the AllergyIntolerance.note element should be used. AllergyIntolerance.note (note) is equivalent to AllergyIntolerance.note Element `AllergyIntolerance.note` is mapped to FHIR R4 element `AllergyIntolerance.note` as `Equivalent`. For example: including reason for flagging a seriousness of 'High Risk'; and instructions related to future exposure or administration of the substance, such as administration within an Intensive Care Unit or under corticosteroid cover. The notes should be related to an allergy or intolerance as a condition in general and not related to any particular episode of it. For episode notes and descriptions, use AllergyIntolerance.event.description and AllergyIntolerance.event.notes. AllergyIntolerance.reaction (reaction) maps to wider concept AllergyIntolerance.reaction Element `AllergyIntolerance.reaction` is mapped to FHIR R4 element `AllergyIntolerance.reaction` as `Equivalent`. AllergyIntolerance.reaction.substance (substance) is equivalent to AllergyIntolerance.reaction.substance Element `AllergyIntolerance.reaction.substance` is mapped to FHIR R4 element `AllergyIntolerance.reaction.substance` as `Equivalent`. Coding of the specific substance (or pharmaceutical product) with a terminology capable of triggering decision support should be used wherever possible. The 'code' element allows for the use of a specific substance or pharmaceutical product, or a group or class of substances. In the case of an allergy or intolerance to a class of substances, (for example, "penicillins"), the 'reaction.substance' element could be used to code the specific substance that was identified as having caused the reaction (for example, "amoxycillin"). Duplication of the value in the 'code' and 'reaction.substance' elements is acceptable when a specific substance has been recorded in 'code'. AllergyIntolerance.reaction.manifestation (manifestation) maps to wider concept AllergyIntolerance.reaction.manifestation Element `AllergyIntolerance.reaction.manifestation` is mapped to FHIR R4 element `AllergyIntolerance.reaction.manifestation` as `SourceIsBroaderThanTarget`. The mappings for `AllergyIntolerance.reaction.manifestation` do not cover the following types: CodeableReference. The mappings for `AllergyIntolerance.reaction.manifestation` do not cover the following types based on type expansion: reference. Manifestation can be expressed as a single word, phrase or brief description. For example: nausea, rash or no reaction. It is preferable that manifestation should be coded with a terminology, where possible. The values entered here may be used to display on an application screen as part of a list of adverse reactions, as recommended in the UK NHS CUI guidelines. Terminologies commonly used include, but are not limited to, SNOMED CT or ICD10. AllergyIntolerance.reaction.description (description) is equivalent to AllergyIntolerance.reaction.description Element `AllergyIntolerance.reaction.description` is mapped to FHIR R4 element `AllergyIntolerance.reaction.description` as `Equivalent`. Use the description to provide any details of a particular event of the occurred reaction such as circumstances, reaction specifics, what happened before/after. Information, related to the event, but not describing a particular care should be captured in the note field. For example: at the age of four, the patient was given penicillin for strep throat and subsequently developed severe hives. AllergyIntolerance.reaction.onset (onset) is equivalent to AllergyIntolerance.reaction.onset Element `AllergyIntolerance.reaction.onset` is mapped to FHIR R4 element `AllergyIntolerance.reaction.onset` as `Equivalent`. AllergyIntolerance.reaction.severity (severity) is equivalent to AllergyIntolerance.reaction.severity Element `AllergyIntolerance.reaction.severity` is mapped to FHIR R4 element `AllergyIntolerance.reaction.severity` as `Equivalent`. It is acknowledged that this assessment is very subjective. There may be some specific practice domains where objective scales have been applied. Objective scales can be included in this model as extensions. AllergyIntolerance.reaction.exposureRoute (exposureRoute) is equivalent to AllergyIntolerance.reaction.exposureRoute Element `AllergyIntolerance.reaction.exposureRoute` is mapped to FHIR R4 element `AllergyIntolerance.reaction.exposureRoute` as `Equivalent`. Coding of the route of exposure with a terminology should be used wherever possible. AllergyIntolerance.reaction.note (note) is equivalent to AllergyIntolerance.reaction.note Element `AllergyIntolerance.reaction.note` is mapped to FHIR R4 element `AllergyIntolerance.reaction.note` as `Equivalent`. Use this field to record information indirectly related to a particular event and not captured in the description. For example: Clinical records are no longer available, recorded based on information provided to the patient by her mother and her mother is deceased. Group 2 Mapping from http://hl7.org/fhir/StructureDefinition/AllergyIntolerance|5.0.0 to R5: unconfirmed | presumed | confirmed | refuted | entered-in-errorversion: 0.1.0) Source Code Relationship Target Code Comment AllergyIntolerance.verificationStatus (verificationStatus) is equivalent to Extension (R5: unconfirmed | presumed | confirmed | refuted | entered-in-error) Element `AllergyIntolerance.verificationStatus` is mapped to FHIR R4 element `AllergyIntolerance.verificationStatus` as `SourceIsBroaderThanTarget`. The target context `AllergyIntolerance.verificationStatus` is a modifier element, so this extension does not need to be defined as a modifier. The data type is CodeableConcept because verificationStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity. Group 3 Mapping from http://hl7.org/fhir/StructureDefinition/AllergyIntolerance|5.0.0 to R5: type additional typesversion: 0.1.0) Source Code Relationship Target Code Comment AllergyIntolerance.type (type) is equivalent to Extension (R5: type additional types) Element `AllergyIntolerance.type` is mapped to FHIR R4 element `AllergyIntolerance.type` as `SourceIsBroaderThanTarget`. The mappings for `AllergyIntolerance.type` do not cover the following types: CodeableConcept. The mappings for `AllergyIntolerance.type` do not cover the following types based on type expansion: coding. Allergic (typically immune-mediated) reactions have been traditionally regarded as an indicator for potential escalation to significant future risk. Contemporary knowledge suggests that some reactions previously thought to be immune-mediated are, in fact, non-immune, but in some cases can still pose a life threatening risk. It is acknowledged that many clinicians might not be in a position to distinguish the mechanism of a particular reaction. Often the term "allergy" is used rather generically and may overlap with the use of "intolerance" - in practice the boundaries between these two concepts might not be well-defined or understood. This data element is included nevertheless, because many legacy systems have captured this attribute. Immunologic testing may provide supporting evidence for the basis of the reaction and the causative substance, but no tests are 100% sensitive or specific for sensitivity to a particular substance. If, as is commonly the case, it is unclear whether the reaction is due to an allergy or an intolerance, then the type element should be omitted from the resource. Group 4 Mapping from http://hl7.org/fhir/StructureDefinition/AllergyIntolerance|5.0.0 to R5: Who or what participated in the activities related to the allergy or intolerance and how they were involved (new)version: 0.1.0) Source Code Relationship Target Code Comment AllergyIntolerance.participant (participant) maps to wider concept Extension (R5: Who or what participated in the activities related to the allergy or intolerance and how they were involved (new)) Element `AllergyIntolerance.participant` has a context of AllergyIntolerance based on following the parent source element upwards and mapping to `AllergyIntolerance`. Element `AllergyIntolerance.participant` has no mapping targets in FHIR R4. Typically, this is because the element has been added (is a new element). AllergyIntolerance.participant.function (function) maps to wider concept Extension.extension:function (R5: Type of involvement (new)) Element `AllergyIntolerance.participant.function` is part of an existing definition because parent element `AllergyIntolerance.participant` requires a cross-version extension. Element `AllergyIntolerance.participant.function` has a context of AllergyIntolerance based on following the parent source element upwards and mapping to `AllergyIntolerance`. Element `AllergyIntolerance.participant.function` has no mapping targets in FHIR R4. Typically, this is because the element has been added (is a new element). AllergyIntolerance.participant.actor (actor) maps to wider concept Extension.extension:actor (R5: Who or what participated in the activities related to the allergy or intolerance (new)) Element `AllergyIntolerance.participant.actor` is part of an existing definition because parent element `AllergyIntolerance.participant` requires a cross-version extension. Element `AllergyIntolerance.participant.actor` has a context of AllergyIntolerance based on following the parent source element upwards and mapping to `AllergyIntolerance`. Element `AllergyIntolerance.participant.actor` has no mapping targets in FHIR R4. Typically, this is because the element has been added (is a new element). Group 5 Mapping from http://hl7.org/fhir/StructureDefinition/AllergyIntolerance|5.0.0 to R5: manifestation additional typesversion: 0.1.0) Source Code Relationship Target Code Comment AllergyIntolerance.reaction.manifestation (manifestation) is equivalent to Extension (R5: manifestation additional types) Element `AllergyIntolerance.reaction.manifestation` is mapped to FHIR R4 element `AllergyIntolerance.reaction.manifestation` as `SourceIsBroaderThanTarget`. The mappings for `AllergyIntolerance.reaction.manifestation` do not cover the following types: CodeableReference. The mappings for `AllergyIntolerance.reaction.manifestation` do not cover the following types based on type expansion: reference. Manifestation can be expressed as a single word, phrase or brief description. For example: nausea, rash or no reaction. It is preferable that manifestation should be coded with a terminology, where possible. The values entered here may be used to display on an application screen as part of a list of adverse reactions, as recommended in the UK NHS CUI guidelines. Terminologies commonly used include, but are not limited to, SNOMED CT or ICD10.
Cross-version mapping for FHIR R5 AllergyIntolerance to FHIR R4 AllergyIntolerance
This ConceptMap represents cross-version mappings for elements from a FHIR R5 AllergyIntolerance to FHIR R4.
Element `AllergyIntolerance.meta` is mapped to FHIR R4 element `AllergyIntolerance.meta` as `Equivalent`.
Element `AllergyIntolerance.implicitRules` is mapped to FHIR R4 element `AllergyIntolerance.implicitRules` as `Equivalent`. Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of its narrative along with other profiles, value sets, etc.
Element `AllergyIntolerance.language` is mapped to FHIR R4 element `AllergyIntolerance.language` as `Equivalent`. 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).
Element `AllergyIntolerance.text` is mapped to FHIR R4 element `AllergyIntolerance.text` as `Equivalent`. Contained resources do not have a narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later.
Element `AllergyIntolerance.contained` is mapped to FHIR R4 element `AllergyIntolerance.contained` as `Equivalent`. 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.
Element `AllergyIntolerance.identifier` is mapped to FHIR R4 element `AllergyIntolerance.identifier` as `Equivalent`. This is a business identifier, not a resource identifier (see [discussion](https://hl7.org/fhir/resource.htm#identifiers)). It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types. For example, multiple Patient and a Person resource instance might share the same social insurance number.
Element `AllergyIntolerance.clinicalStatus` is mapped to FHIR R4 element `AllergyIntolerance.clinicalStatus` as `Equivalent`. AllergyIntolerance.clinicalStatus should be present if verificationStatus is not entered-in-error and the AllergyIntolerance.code isn't negated (No Known Allergy, No Drug Allergy, No Food Allergy, No Latex Allergy). Refer to [discussion](https://hl7.org/fhir/extensibility.html#Special-Case) if clinicalStatus is missing data. The data type is CodeableConcept because clinicalStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity.
Element `AllergyIntolerance.verificationStatus` is mapped to FHIR R4 element `AllergyIntolerance.verificationStatus` as `SourceIsBroaderThanTarget`. The target context `AllergyIntolerance.verificationStatus` is a modifier element, so this extension does not need to be defined as a modifier. The data type is CodeableConcept because verificationStatus has some clinical judgment involved, such that there might need to be more specificity than the required FHIR value set allows. For example, a SNOMED coding might allow for additional specificity.
Element `AllergyIntolerance.type` is mapped to FHIR R4 element `AllergyIntolerance.type` as `SourceIsBroaderThanTarget`. The mappings for `AllergyIntolerance.type` do not cover the following types: CodeableConcept. The mappings for `AllergyIntolerance.type` do not cover the following types based on type expansion: coding. Allergic (typically immune-mediated) reactions have been traditionally regarded as an indicator for potential escalation to significant future risk. Contemporary knowledge suggests that some reactions previously thought to be immune-mediated are, in fact, non-immune, but in some cases can still pose a life threatening risk. It is acknowledged that many clinicians might not be in a position to distinguish the mechanism of a particular reaction. Often the term "allergy" is used rather generically and may overlap with the use of "intolerance" - in practice the boundaries between these two concepts might not be well-defined or understood. This data element is included nevertheless, because many legacy systems have captured this attribute. Immunologic testing may provide supporting evidence for the basis of the reaction and the causative substance, but no tests are 100% sensitive or specific for sensitivity to a particular substance. If, as is commonly the case, it is unclear whether the reaction is due to an allergy or an intolerance, then the type element should be omitted from the resource.
Element `AllergyIntolerance.category` is mapped to FHIR R4 element `AllergyIntolerance.category` as `Equivalent`. This data element has been included because it is currently being captured in some clinical systems. This data can be derived from the substance where coding systems are used, and is effectively redundant in that situation. When searching on category, consider the implications of AllergyIntolerance resources without a category. For example, when searching on category = medication, medication allergies that don't have a category valued will not be returned. Refer to [search](https://hl7.org/fhir/search.html) for more information on how to search category with a :missing modifier to get allergies that don't have a category. Additionally, category should be used with caution because category can be subjective based on the sender.
Element `AllergyIntolerance.criticality` is mapped to FHIR R4 element `AllergyIntolerance.criticality` as `Equivalent`. The default criticality value for any propensity to an adverse reaction should be 'Low Risk', indicating at the very least a relative contraindication to deliberate or voluntary exposure to the substance. 'High Risk' is flagged if the clinician has identified a propensity for a more serious or potentially life-threatening reaction, such as anaphylaxis, and implies an absolute contraindication to deliberate or voluntary exposure to the substance. If this element is missing, the criticality is unknown (though it may be known elsewhere). Systems that capture a severity at the condition level are actually representing the concept of criticality whereas the severity documented at the reaction level is representing the true reaction severity. Existing systems that are capturing both condition criticality and reaction severity may use the term "severity" to represent both. Criticality is the worst it could be in the future (i.e. situation-agnostic) whereas severity is situation-dependent.
Element `AllergyIntolerance.code` is mapped to FHIR R4 element `AllergyIntolerance.code` as `Equivalent`. It is strongly recommended that this element be populated using a terminology, where possible. For example, some terminologies used include RxNorm, SNOMED CT, DM+D, NDFRT, ICD-9, IDC-10, UNII, and ATC. Plain text should only be used if there is no appropriate terminology available. Additional details can be specified in the text. When a substance or product code is specified for the 'code' element, the "default" semantic context is that this is a positive statement of an allergy or intolerance (depending on the value of the 'type' element, if present) condition to the specified substance/product. In the corresponding SNOMED CT allergy model, the specified substance/product is the target (destination) of the "Causative agent" relationship. The 'substanceExposureRisk' extension is available as a structured and more flexible alternative to the 'code' element for making positive or negative allergy or intolerance statements. This extension provides the capability to make "no known allergy" (or "no risk of adverse reaction") statements regarding any coded substance/product (including cases when a pre-coordinated "no allergy to x" concept for that substance/product does not exist). If the 'substanceExposureRisk' extension is present, the AllergyIntolerance.code element SHALL be omitted.
Element `AllergyIntolerance.patient` is mapped to FHIR R4 element `AllergyIntolerance.patient` as `Equivalent`.
Element `AllergyIntolerance.encounter` is mapped to FHIR R4 element `AllergyIntolerance.encounter` as `Equivalent`.
Element `AllergyIntolerance.onset[x]` is mapped to FHIR R4 element `AllergyIntolerance.onset[x]` as `Equivalent`. The target context `AllergyIntolerance.onset[x]` is a choice-type element and cannot directly hold extensions. The context is moved up to parent element `AllergyIntolerance`. Age is generally used when the patient reports an age at which the AllergyIntolerance was noted. Period is generally used to convey an imprecise onset that occurred within the time period. Range is generally used to convey an imprecise age range (e.g. 4 to 6 years old).
Element `AllergyIntolerance.recordedDate` is mapped to FHIR R4 element `AllergyIntolerance.recordedDate` as `Equivalent`. When onset date is unknown, recordedDate can be used to establish if the allergy or intolerance was present on or before a given date. If the recordedDate is known and provided by a sending system, it is preferred that the receiving system preserve that recordedDate value. If the recordedDate is not provided by the sending system, the receipt timestamp is sometimes used as the recordedDate.
Element `AllergyIntolerance.lastOccurrence` is mapped to FHIR R4 element `AllergyIntolerance.lastOccurrence` as `Equivalent`. This date may be replicated by one of the Onset of Reaction dates. Where a textual representation of the date of last occurrence is required e.g. 'In Childhood, '10 years ago' the AllergyIntolerance.note element should be used.
Element `AllergyIntolerance.note` is mapped to FHIR R4 element `AllergyIntolerance.note` as `Equivalent`. For example: including reason for flagging a seriousness of 'High Risk'; and instructions related to future exposure or administration of the substance, such as administration within an Intensive Care Unit or under corticosteroid cover. The notes should be related to an allergy or intolerance as a condition in general and not related to any particular episode of it. For episode notes and descriptions, use AllergyIntolerance.event.description and AllergyIntolerance.event.notes.
Element `AllergyIntolerance.reaction` is mapped to FHIR R4 element `AllergyIntolerance.reaction` as `Equivalent`.
Element `AllergyIntolerance.reaction.substance` is mapped to FHIR R4 element `AllergyIntolerance.reaction.substance` as `Equivalent`. Coding of the specific substance (or pharmaceutical product) with a terminology capable of triggering decision support should be used wherever possible. The 'code' element allows for the use of a specific substance or pharmaceutical product, or a group or class of substances. In the case of an allergy or intolerance to a class of substances, (for example, "penicillins"), the 'reaction.substance' element could be used to code the specific substance that was identified as having caused the reaction (for example, "amoxycillin"). Duplication of the value in the 'code' and 'reaction.substance' elements is acceptable when a specific substance has been recorded in 'code'.
Element `AllergyIntolerance.reaction.manifestation` is mapped to FHIR R4 element `AllergyIntolerance.reaction.manifestation` as `SourceIsBroaderThanTarget`. The mappings for `AllergyIntolerance.reaction.manifestation` do not cover the following types: CodeableReference. The mappings for `AllergyIntolerance.reaction.manifestation` do not cover the following types based on type expansion: reference. Manifestation can be expressed as a single word, phrase or brief description. For example: nausea, rash or no reaction. It is preferable that manifestation should be coded with a terminology, where possible. The values entered here may be used to display on an application screen as part of a list of adverse reactions, as recommended in the UK NHS CUI guidelines. Terminologies commonly used include, but are not limited to, SNOMED CT or ICD10.
Element `AllergyIntolerance.reaction.description` is mapped to FHIR R4 element `AllergyIntolerance.reaction.description` as `Equivalent`. Use the description to provide any details of a particular event of the occurred reaction such as circumstances, reaction specifics, what happened before/after. Information, related to the event, but not describing a particular care should be captured in the note field. For example: at the age of four, the patient was given penicillin for strep throat and subsequently developed severe hives.
Element `AllergyIntolerance.reaction.onset` is mapped to FHIR R4 element `AllergyIntolerance.reaction.onset` as `Equivalent`.
Element `AllergyIntolerance.reaction.severity` is mapped to FHIR R4 element `AllergyIntolerance.reaction.severity` as `Equivalent`. It is acknowledged that this assessment is very subjective. There may be some specific practice domains where objective scales have been applied. Objective scales can be included in this model as extensions.
Element `AllergyIntolerance.reaction.exposureRoute` is mapped to FHIR R4 element `AllergyIntolerance.reaction.exposureRoute` as `Equivalent`. Coding of the route of exposure with a terminology should be used wherever possible.
Element `AllergyIntolerance.reaction.note` is mapped to FHIR R4 element `AllergyIntolerance.reaction.note` as `Equivalent`. Use this field to record information indirectly related to a particular event and not captured in the description. For example: Clinical records are no longer available, recorded based on information provided to the patient by her mother and her mother is deceased.
Element `AllergyIntolerance.participant` has a context of AllergyIntolerance based on following the parent source element upwards and mapping to `AllergyIntolerance`. Element `AllergyIntolerance.participant` has no mapping targets in FHIR R4. Typically, this is because the element has been added (is a new element).
Element `AllergyIntolerance.participant.function` is part of an existing definition because parent element `AllergyIntolerance.participant` requires a cross-version extension. Element `AllergyIntolerance.participant.function` has a context of AllergyIntolerance based on following the parent source element upwards and mapping to `AllergyIntolerance`. Element `AllergyIntolerance.participant.function` has no mapping targets in FHIR R4. Typically, this is because the element has been added (is a new element).
Element `AllergyIntolerance.participant.actor` is part of an existing definition because parent element `AllergyIntolerance.participant` requires a cross-version extension. Element `AllergyIntolerance.participant.actor` has a context of AllergyIntolerance based on following the parent source element upwards and mapping to `AllergyIntolerance`. Element `AllergyIntolerance.participant.actor` has no mapping targets in FHIR R4. Typically, this is because the element has been added (is a new element).