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Medication Statement Profile

Canonical../StructureDefinition/nexus-emr-core-medicationstatement
Statusdraft (experimental) · 1.26.0
BaseMedicationStatement (constraint)
SourceFSH · JSON

Nexus EMR profile for MedicationStatement -- patient-reported medication use, distinct from prescriptions. First pass: status, text-first medication concept, effective timing, free-text dosage. Closed to SMART apps pending an exposure decision.

Elements / Details

Every element this profile touches, with its full definition. Element names in the tables link here.

MedicationStatement

Short Nexus EMR Medication Statement Core
Definition A record of a medication that is being consumed by a patient. A MedicationStatement may indicate that the patient may be taking the medication now or has taken the medication in the past or will be taking the medication in the future. The source of this information can be the patient, significant other (such as a family member or spouse), or a clinician. A common scenario where this information is captured is during the history taking process during a patient visit or stay. The medication information may come from sources such as the patient's memory, from a prescription bottle, or from a list of medications the patient, clinician or other party maintains. The primary difference between a medication statement and a medication administration is that the medication administration has complete administration information and is based on actual administration information from the person who administered the medication. A medication statement is often, if not always, less specific. There is no required date/time when the medication was administered, in fact we only know that a source has reported the patient is taking this medication, where details such as time, quantity, or rate or even medication product may be incomplete or missing or less precise. As stated earlier, the medication statement information may come from the patient's memory, from a prescription bottle or from a list of medications the patient, clinician or other party maintains. Medication administration is more formal and is not missing detailed information.
Comments When interpreting a medicationStatement, the value of the status and NotTaken needed to be considered: MedicationStatement.status + MedicationStatement.wasNotTaken Status=Active + NotTaken=T = Not currently taking Status=Completed + NotTaken=T = Not taken in the past Status=Intended + NotTaken=T = No intention of taking Status=Active + NotTaken=F = Taking, but not as prescribed Status=Active + NotTaken=F = Taking Status=Intended +NotTaken= F = Will be taking (not started) Status=Completed + NotTaken=F = Taken in past Status=In Error + NotTaken=N/A = In Error.
Cardinality 0..*
Invariants dom-2, dom-3, dom-4, dom-5, dom-6, nexus-note-extension-not-where-native

MedicationStatement.id

Short Logical id of this artifact
Definition The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.
Comments The only time that a resource does not have an id is when it is being submitted to the server using a create operation.
Cardinality 0..1
Type http://hl7.org/fhirpath/System.String

MedicationStatement.meta

Short Metadata about the resource
Definition 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.
Cardinality 0..1
Type Meta
Invariants ele-1

MedicationStatement.implicitRules

Short A set of rules under which this content was created
Definition 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.
Comments 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.
Cardinality 0..1
Type uri
Modifier yes — This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
Invariants ele-1

MedicationStatement.language

Short Language of the resource content
Definition The base language in which the resource is written.
Comments 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).
Cardinality 0..1
Type code
Binding languages (preferred)
Invariants ele-1

MedicationStatement.text

Short Text summary of the resource, for human interpretation
Definition 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.
Comments 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.
Cardinality 0..1
Type Narrative
Invariants ele-1
Also called narrative, html, xhtml, display

MedicationStatement.contained

Short Contained, inline Resources
Definition 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.
Comments 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.
Cardinality 0..*
Type Resource
Also called inline resources, anonymous resources, contained resources

MedicationStatement.extension

Short Additional content defined by implementations
Definition 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.
Comments 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.
Cardinality 0..*
Type Extension
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.modifierExtension

Short Extensions that cannot be ignored
Definition 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).
Requirements 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.
Comments 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.
Cardinality 0..*
Type Extension
Modifier yes — Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.identifier

Short External identifier
Definition Identifiers associated with this Medication Statement that are defined by business processes and/or used to refer to it when a direct URL reference to the resource itself is not appropriate. They are business identifiers assigned to this resource by the performer or other systems and remain constant as the resource is updated and propagates from server to server.
Comments This is a business identifier, not a resource identifier.
Cardinality 0..*
Type Identifier
Invariants ele-1

MedicationStatement.basedOn

Short Fulfils plan, proposal or order
Definition A plan, proposal or order that is fulfilled in whole or in part by this event.
Requirements Allows tracing of authorization for the event and tracking whether proposals/recommendations were acted upon.
Cardinality 0..*
Type Reference(MedicationRequest | CarePlan | ServiceRequest)
Invariants ele-1

MedicationStatement.partOf

Short Part of referenced event
Definition A larger event of which this particular event is a component or step.
Requirements This should not be used when indicating which resource a MedicationStatement has been derived from. If that is the use case, then MedicationStatement.derivedFrom should be used.
Cardinality 0..*
Type Reference(MedicationAdministration | MedicationDispense | MedicationStatement | Procedure | Observation)
Invariants ele-1

MedicationStatement.status

Short active | completed | entered-in-error | intended | stopped | on-hold | unknown | not-taken
Definition A code representing the patient or other source's judgment about the state of the medication used that this statement is about. Generally, this will be active or completed.
Comments This is a modifier element; not-taken inverts the meaning of the whole statement and consumers must read it.
Cardinality 1..1
Type code
Must Support yes
Modifier yes — This element is labelled as a modifier because it is a status element that contains status entered-in-error which means that the resource should not be treated as valid
Binding medication-statement-status (required)
Invariants ele-1

MedicationStatement.statusReason

Short Reason for current status
Definition Captures the reason for the current state of the MedicationStatement.
Comments This is generally only used for "exception" statuses such as "not-taken", "on-hold", "cancelled" or "entered-in-error". The reason for performing the event at all is captured in reasonCode, not here.
Cardinality 0..*
Type CodeableConcept
Binding reason-medication-status-codes (example)
Invariants ele-1

MedicationStatement.category

Short Type of medication usage
Definition Indicates where the medication is expected to be consumed or administered.
Cardinality 0..1
Type CodeableConcept
Binding medication-statement-category (preferred)
Invariants ele-1

MedicationStatement.medication[x]

Short The medication the patient reports taking
Definition First pass constrains to CodeableConcept: the platform has no Medication catalog resource to reference, and patient-reported meds frequently arrive as free text. Carry text for readability. Where the source has codes, carry them at both levels: an ingredient-level code (CCDD preferred, otherwise the Health Canada DPD active-ingredient group number, with ATC for class-level records) is what lets a patient-reported medication be compared against a prescription or against a recorded allergy, and a DIN says which marketed product the patient named. Both slices are optional -- a patient report often has neither -- and neither is to be synthesized from the text.
Comments Text carries readability; product (DIN) and ingredient (CCDD/ATC) codings are optional. Where this code was mapped from a source system's own vocabulary, carry the raw coding alongside the mapped one, flagged userSelected = true. See Carrying the raw code.
Cardinality 1..1
Type CodeableConcept
Must Support yes
Binding medication-codes (example)
Invariants ele-1

MedicationStatement.medication[x].id

Short Unique id for inter-element referencing
Definition Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Cardinality 0..1
Type http://hl7.org/fhirpath/System.String

MedicationStatement.medication[x].extension

Short Additional content defined by implementations
Definition 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.
Comments 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.
Cardinality 0..*
Type Extension
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.medication[x].coding

Short Code defined by a terminology system
Definition A reference to a code defined by a terminology system.
Requirements Allows for alternative encodings within a code system, and translations to other code systems.
Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true.
Cardinality 0..*
Type Coding
Invariants ele-1

MedicationStatement.medication[x].coding:din

Short The Health Canada Drug Identification Number for the marketed product
Definition Drug Identification Number, when the source has one. Product level: it identifies one manufacturer's product, so it is the right code to carry and the wrong code to match on. The representative-DIN strategy this follows originates in the PrescribeIT specification.
Requirements Allows for alternative encodings within a code system, and translations to other code systems.
Comments SYSTEM URI CHANGED. This specification previously fixed http://hl7.org/fhir/sid/ca-hc-din on this slice, and stored data and existing integrations may still carry that value. The system is now http://hl7.org/fhir/NamingSystem/ca-hc-din, which is the URI HL7 Terminology records as the official canonical going forward and the URI the code system is served at; http://terminology.hl7.org/CodeSystem/ca-hc-din is retained upstream for backward compatibility. The stable identity across every spelling is the OID 2.16.840.1.113883.5.1105. WHAT TO DO: write the NamingSystem form, and be liberal in what you accept when reading -- treat all of these spellings as the same code system until your own data no longer carries the others.
Cardinality 0..*
Type Coding
Must Support yes
Invariants ele-1

MedicationStatement.medication[x].coding:din.id

Short Unique id for inter-element referencing
Definition Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Cardinality 0..1
Type http://hl7.org/fhirpath/System.String

MedicationStatement.medication[x].coding:din.extension

Short Additional content defined by implementations
Definition 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.
Comments 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.
Cardinality 0..*
Type Extension
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.medication[x].coding:din.system

Short Identity of the terminology system
Definition The identification of the code system that defines the meaning of the symbol in the code.
Requirements Need to be unambiguous about the source of the definition of the symbol.
Comments Fixed to http://hl7.org/fhir/NamingSystem/ca-hc-din. A reader encountering http://hl7.org/fhir/sid/ca-hc-din on stored data is looking at the URI this specification fixed previously; it names the same code system (OID 2.16.840.1.113883.5.1105) and should be accepted as equivalent on ingest.
Cardinality 1..1
Type uri
Fixed value http://hl7.org/fhir/NamingSystem/ca-hc-din
Invariants ele-1

MedicationStatement.medication[x].coding:din.version

Short Version of the system - if relevant
Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged.
Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.medication[x].coding:din.code

Short Symbol in syntax defined by the system
Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination).
Requirements Need to refer to a particular code in the system.
Cardinality 1..1
Type code
Invariants ele-1

MedicationStatement.medication[x].coding:din.display

Short Representation defined by the system
Definition A representation of the meaning of the code in the system, following the rules of the system.
Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.medication[x].coding:din.userSelected

Short If this coding was chosen directly by the user
Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing.
Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely.
Cardinality 0..1
Type boolean
Invariants ele-1

MedicationStatement.medication[x].coding:ccdd

Short CCDD — what the drug IS (preferred ingredient-level code)
Definition Canadian Clinical Drug Data Set code. Ingredient level, and the code to prefer for any cross-record comparison: same-drug detection, duplicate therapy, and matching against a recorded allergy. Codes are not enumerated in this IG; the slot and the system are declared here and the content is governed by its publisher.
Requirements Allows for alternative encodings within a code system, and translations to other code systems.
Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true.
Cardinality 0..*
Type Coding
Must Support yes
Invariants ele-1

MedicationStatement.medication[x].coding:ccdd.id

Short Unique id for inter-element referencing
Definition Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Cardinality 0..1
Type http://hl7.org/fhirpath/System.String

MedicationStatement.medication[x].coding:ccdd.extension

Short Additional content defined by implementations
Definition 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.
Comments 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.
Cardinality 0..*
Type Extension
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.medication[x].coding:ccdd.system

Short Identity of the terminology system
Definition The identification of the code system that defines the meaning of the symbol in the code.
Requirements Need to be unambiguous about the source of the definition of the symbol.
Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously.
Cardinality 1..1
Type uri
Fixed value http://terminology.hl7.org/CodeSystem/hc-CCDD
Invariants ele-1

MedicationStatement.medication[x].coding:ccdd.version

Short Version of the system - if relevant
Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged.
Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.medication[x].coding:ccdd.code

Short Symbol in syntax defined by the system
Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination).
Requirements Need to refer to a particular code in the system.
Cardinality 1..1
Type code
Invariants ele-1

MedicationStatement.medication[x].coding:ccdd.display

Short Representation defined by the system
Definition A representation of the meaning of the code in the system, following the rules of the system.
Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.medication[x].coding:ccdd.userSelected

Short If this coding was chosen directly by the user
Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing.
Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely.
Cardinality 0..1
Type boolean
Invariants ele-1

MedicationStatement.medication[x].coding:atc

Short ATC classification — coarser ingredient-level grouping
Definition WHO Anatomical Therapeutic Chemical code. Ingredient level but coarser than CCDD, and useful for class-level questions. Codes are not enumerated in this IG.
Requirements Allows for alternative encodings within a code system, and translations to other code systems.
Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true.
Cardinality 0..*
Type Coding
Must Support yes
Invariants ele-1

MedicationStatement.medication[x].coding:atc.id

Short Unique id for inter-element referencing
Definition Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Cardinality 0..1
Type http://hl7.org/fhirpath/System.String

MedicationStatement.medication[x].coding:atc.extension

Short Additional content defined by implementations
Definition 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.
Comments 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.
Cardinality 0..*
Type Extension
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.medication[x].coding:atc.system

Short Identity of the terminology system
Definition The identification of the code system that defines the meaning of the symbol in the code.
Requirements Need to be unambiguous about the source of the definition of the symbol.
Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously.
Cardinality 1..1
Type uri
Fixed value http://www.whocc.no/atc
Invariants ele-1

MedicationStatement.medication[x].coding:atc.version

Short Version of the system - if relevant
Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged.
Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.medication[x].coding:atc.code

Short Symbol in syntax defined by the system
Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination).
Requirements Need to refer to a particular code in the system.
Cardinality 1..1
Type code
Invariants ele-1

MedicationStatement.medication[x].coding:atc.display

Short Representation defined by the system
Definition A representation of the meaning of the code in the system, following the rules of the system.
Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.medication[x].coding:atc.userSelected

Short If this coding was chosen directly by the user
Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing.
Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely.
Cardinality 0..1
Type boolean
Invariants ele-1

MedicationStatement.medication[x].coding:aign

Short The active-ingredient group identifying the drug's ingredient and strength
Definition Health Canada Drug Product Database active-ingredient group number, ten digits. It gathers the products that share an active-ingredient composition across manufacturer and salt form, so two medication records carrying the same number are the same drug at the same strength, and it covers the whole DIN space -- which makes it the code to match on when CCDD is absent, in practice most legacy EMR medication lists where a DIN and a line of free text is all that exists. The number decomposes as [2 digits: number of active ingredients][5 digits: active-ingredient group][3 digits: strength group], so it is strength-specific. Matching a medication against an allergen coded with the five-digit active-ingredient group (v3-hc-aigc, which AllergyIntolerance binds) means comparing positions 3 through 7 of this number, NOT the number itself. Codes are not enumerated in this IG.
Requirements Allows for alternative encodings within a code system, and translations to other code systems.
Comments The DPD active-ingredient group number (AIGN), reachable from a DIN at a given strength.
Cardinality 0..*
Type Coding
Must Support yes
Invariants ele-1

MedicationStatement.medication[x].coding:aign.id

Short Unique id for inter-element referencing
Definition Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Cardinality 0..1
Type http://hl7.org/fhirpath/System.String

MedicationStatement.medication[x].coding:aign.extension

Short Additional content defined by implementations
Definition 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.
Comments 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.
Cardinality 0..*
Type Extension
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.medication[x].coding:aign.system

Short Identity of the terminology system
Definition The identification of the code system that defines the meaning of the symbol in the code.
Requirements Need to be unambiguous about the source of the definition of the symbol.
Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously.
Cardinality 1..1
Type uri
Fixed value http://terminology.hl7.org/CodeSystem/v3-hc-aign
Invariants ele-1

MedicationStatement.medication[x].coding:aign.version

Short Version of the system - if relevant
Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged.
Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.medication[x].coding:aign.code

Short Symbol in syntax defined by the system
Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination).
Requirements Need to refer to a particular code in the system.
Cardinality 1..1
Type code
Invariants ele-1

MedicationStatement.medication[x].coding:aign.display

Short Representation defined by the system
Definition A representation of the meaning of the code in the system, following the rules of the system.
Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.medication[x].coding:aign.userSelected

Short If this coding was chosen directly by the user
Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing.
Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely.
Cardinality 0..1
Type boolean
Invariants ele-1

MedicationStatement.medication[x].text

Short Plain text representation of the concept
Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user.
Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.
Comments Very often the text is the same as a displayName of one of the codings.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.subject

Short The patient
Definition The person, animal or group who is/was taking the medication.
Cardinality 1..1
Type Reference(Patient Profile)
Must Support yes
Invariants ele-1

MedicationStatement.context

Short Encounter / Episode associated with MedicationStatement
Definition The encounter or episode of care that establishes the context for this MedicationStatement.
Cardinality 0..1
Type Reference(Encounter | EpisodeOfCare)
Invariants ele-1

MedicationStatement.effective[x]

Short When the use applies (dateTime or period)
Definition The interval of time during which it is being asserted that the patient is/was/will be taking the medication (or was not taking, when the MedicationStatement.taken element is No).
Comments This attribute reflects the period over which the patient consumed the medication and is expected to be populated on the majority of Medication Statements. If the medication is still being taken at the time the statement is recorded, the "end" date will be omitted. The date/time attribute supports a variety of dates - year, year/month and exact date. If something more than this is required, this should be conveyed as text.
Cardinality 0..1
Type dateTime, Period
Must Support yes
Invariants ele-1

MedicationStatement.dateAsserted

Short When the statement was captured
Definition The date when the medication statement was asserted by the information source.
Cardinality 0..1
Type dateTime
Must Support yes
Invariants ele-1

MedicationStatement.informationSource

Short Person or organization that provided the information about the taking of this medication
Definition The person or organization that provided the information about the taking of this medication. Note: Use derivedFrom when a MedicationStatement is derived from other resources, e.g. Claim or MedicationRequest.
Cardinality 0..1
Type Reference(Patient | Practitioner | PractitionerRole | RelatedPerson | Organization)
Invariants ele-1

MedicationStatement.derivedFrom

Short Additional supporting information
Definition Allows linking the MedicationStatement to the underlying MedicationRequest, or to other information that supports or is used to derive the MedicationStatement.
Comments Likely references would be to MedicationRequest, MedicationDispense, Claim, Observation or QuestionnaireAnswers. The most common use cases for deriving a MedicationStatement comes from creating a MedicationStatement from a MedicationRequest or from a lab observation or a claim. it should be noted that the amount of information that is available varies from the type resource that you derive the MedicationStatement from.
Cardinality 0..*
Type Reference(Resource)
Invariants ele-1

MedicationStatement.reasonCode

Short Reason for why the medication is being/was taken
Definition A reason for why the medication is being/was taken.
Comments This could be a diagnosis code. If a full condition record exists or additional detail is needed, use reasonForUseReference.
Cardinality 0..*
Type CodeableConcept
Binding condition-code (example)
Invariants ele-1

MedicationStatement.reasonReference

Short Condition or observation that supports why the medication is being/was taken
Definition Condition or observation that supports why the medication is being/was taken.
Comments This is a reference to a condition that is the reason why the medication is being/was taken. If only a code exists, use reasonForUseCode.
Cardinality 0..*
Type Reference(Condition | Observation | DiagnosticReport)
Invariants ele-1

MedicationStatement.note

Short Further information about the statement
Definition Provides extra information about the medication statement that is not conveyed by the other attributes.
Cardinality 0..*
Type Annotation
Invariants ele-1

MedicationStatement.dosage

Short Details of how medication is/was taken or should be taken
Definition Indicates how the medication is/was or should be taken by the patient.
Comments The dates included in the dosage on a Medication Statement reflect the dates for a given dose. For example, "from November 1, 2016 to November 3, 2016, take one tablet daily and from November 4, 2016 to November 7, 2016, take two tablets daily." It is expected that this specificity may only be populated where the patient brings in their labeled container or where the Medication Statement is derived from a MedicationRequest.
Cardinality 0..*
Type Dosage
Must Support yes
Invariants ele-1

MedicationStatement.dosage.id

Short Unique id for inter-element referencing
Definition Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Cardinality 0..1
Type http://hl7.org/fhirpath/System.String

MedicationStatement.dosage.extension

Short Additional content defined by implementations
Definition 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.
Comments 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.
Cardinality 0..*
Type Extension
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.dosage.modifierExtension

Short Extensions that cannot be ignored even if unrecognized
Definition 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).
Requirements 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.
Comments 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.
Cardinality 0..*
Type Extension
Modifier yes — Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Invariants ele-1, ext-1
Also called extensions, user content, modifiers

MedicationStatement.dosage.sequence

Short The order of the dosage instructions
Definition Indicates the order in which the dosage instructions should be applied or interpreted.
Requirements If the sequence number of multiple Dosages is the same, then it is implied that the instructions are to be treated as concurrent. If the sequence number is different, then the Dosages are intended to be sequential.
Cardinality 0..1
Type integer
Invariants ele-1

MedicationStatement.dosage.text

Short Free-text dosage ('81 mg daily') -- the first-pass dosage surface
Definition Free text dosage instructions e.g. SIG.
Requirements Free text dosage instructions can be used for cases where the instructions are too complex to code. The content of this attribute does not include the name or description of the medication. When coded instructions are present, the free text instructions may still be present for display to humans taking or administering the medication. It is expected that the text instructions will always be populated. If the dosage.timing attribute is also populated, then the dosage.text should reflect the same information as the timing. Additional information about administration or preparation of the medication should be included as text.
Cardinality 0..1
Type string
Must Support yes
Invariants ele-1

MedicationStatement.dosage.additionalInstruction

Short Supplemental instruction or warnings to the patient - e.g. "with meals", "may cause drowsiness"
Definition Supplemental instructions to the patient on how to take the medication (e.g. "with meals" or"take half to one hour before food") or warnings for the patient about the medication (e.g. "may cause drowsiness" or "avoid exposure of skin to direct sunlight or sunlamps").
Requirements Additional instruction is intended to be coded, but where no code exists, the element could include text. For example, "Swallow with plenty of water" which might or might not be coded.
Comments Information about administration or preparation of the medication (e.g. "infuse as rapidly as possibly via intraperitoneal port" or "immediately following drug x") should be populated in dosage.text.
Cardinality 0..*
Type CodeableConcept
Binding additional-instruction-codes (example)
Invariants ele-1

MedicationStatement.dosage.patientInstruction

Short Patient or consumer oriented instructions
Definition Instructions in terms that are understood by the patient or consumer.
Cardinality 0..1
Type string
Invariants ele-1

MedicationStatement.dosage.timing

Short When medication should be administered
Definition When medication should be administered.
Requirements The timing schedule for giving the medication to the patient. This data type allows many different expressions. For example: "Every 8 hours"; "Three times a day"; "1/2 an hour before breakfast for 10 days from 23-Dec 2011:"; "15 Oct 2013, 17 Oct 2013 and 1 Nov 2013". Sometimes, a rate can imply duration when expressed as total volume / duration (e.g. 500mL/2 hours implies a duration of 2 hours). However, when rate doesn't imply duration (e.g. 250mL/hour), then the timing.repeat.duration is needed to convey the infuse over time period.
Comments This attribute might not always be populated while the Dosage.text is expected to be populated. If both are populated, then the Dosage.text should reflect the content of the Dosage.timing.
Cardinality 0..1
Type Timing
Invariants ele-1

MedicationStatement.dosage.asNeeded[x]

Short Take "as needed" (for x)
Definition Indicates whether the Medication is only taken when needed within a specific dosing schedule (Boolean option), or it indicates the precondition for taking the Medication (CodeableConcept).
Comments Can express "as needed" without a reason by setting the Boolean = True. In this case the CodeableConcept is not populated. Or you can express "as needed" with a reason by including the CodeableConcept. In this case the Boolean is assumed to be True. If you set the Boolean to False, then the dose is given according to the schedule and is not "prn" or "as needed".
Cardinality 0..1
Type boolean, CodeableConcept
Binding medication-as-needed-reason (example)
Invariants ele-1

MedicationStatement.dosage.site

Short Body site to administer to
Definition Body site to administer to.
Requirements A coded specification of the anatomic site where the medication first enters the body.
Comments If the use case requires attributes from the BodySite resource (e.g. to identify and track separately) then use the standard extension bodySite. May be a summary code, or a reference to a very precise definition of the location, or both.
Cardinality 0..1
Type CodeableConcept
Binding approach-site-codes (example)
Invariants ele-1

MedicationStatement.dosage.route

Short How drug should enter body
Definition How drug should enter body.
Requirements A code specifying the route or physiological path of administration of a therapeutic agent into or onto a patient's body.
Cardinality 0..1
Type CodeableConcept
Binding route-codes (example)
Invariants ele-1

MedicationStatement.dosage.method

Short Technique for administering medication
Definition Technique for administering medication.
Requirements A coded value indicating the method by which the medication is introduced into or onto the body. Most commonly used for injections. For examples, Slow Push; Deep IV.
Comments Terminologies used often pre-coordinate this term with the route and or form of administration.
Cardinality 0..1
Type CodeableConcept
Binding administration-method-codes (example)
Invariants ele-1

MedicationStatement.dosage.doseAndRate

Short Amount of medication administered
Definition The amount of medication administered.
Cardinality 0..*
Type Element
Invariants ele-1

MedicationStatement.dosage.doseAndRate.id

Short Unique id for inter-element referencing
Definition Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
Cardinality 0..1
Type http://hl7.org/fhirpath/System.String

MedicationStatement.dosage.doseAndRate.extension

Short Additional content defined by implementations
Definition 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.
Comments 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.
Cardinality 0..*
Type Extension
Invariants ele-1, ext-1
Also called extensions, user content

MedicationStatement.dosage.doseAndRate.type

Short The kind of dose or rate specified
Definition The kind of dose or rate specified, for example, ordered or calculated.
Requirements If the type is not populated, assume to be "ordered".
Cardinality 0..1
Type CodeableConcept
Binding dose-rate-type (example)
Invariants ele-1

MedicationStatement.dosage.doseAndRate.dose[x]

Short Amount of medication per dose
Definition Amount of medication per dose.
Requirements The amount of therapeutic or other substance given at one administration event.
Comments Note that this specifies the quantity of the specified medication, not the quantity for each active ingredient(s). Each ingredient amount can be communicated in the Medication resource. For example, if one wants to communicate that a tablet was 375 mg, where the dose was one tablet, you can use the Medication resource to document that the tablet was comprised of 375 mg of drug XYZ. Alternatively if the dose was 375 mg, then you may only need to use the Medication resource to indicate this was a tablet. If the example were an IV such as dopamine and you wanted to communicate that 400mg of dopamine was mixed in 500 ml of some IV solution, then this would all be communicated in the Medication resource. If the administration is not intended to be instantaneous (rate is present or timing has a duration), this can be specified to convey the total amount to be administered over the period of time as indicated by the schedule e.g. 500 ml in dose, with timing used to convey that this should be done over 4 hours.
Cardinality 0..1
Type Range, Quantity(SimpleQuantity)
Invariants ele-1

MedicationStatement.dosage.doseAndRate.rate[x]

Short Amount of medication per unit of time
Definition Amount of medication per unit of time.
Requirements Identifies the speed with which the medication was or will be introduced into the patient. Typically the rate for an infusion e.g. 100 ml per 1 hour or 100 ml/hr. May also be expressed as a rate per unit of time e.g. 500 ml per 2 hours. Other examples: 200 mcg/min or 200 mcg/1 minute; 1 liter/8 hours. Sometimes, a rate can imply duration when expressed as total volume / duration (e.g. 500mL/2 hours implies a duration of 2 hours). However, when rate doesn't imply duration (e.g. 250mL/hour), then the timing.repeat.duration is needed to convey the infuse over time period.
Comments It is possible to supply both a rate and a doseQuantity to provide full details about how the medication is to be administered and supplied. If the rate is intended to change over time, depending on local rules/regulations, each change should be captured as a new version of the MedicationRequest with an updated rate, or captured with a new MedicationRequest with the new rate. It is possible to specify a rate over time (for example, 100 ml/hour) using either the rateRatio and rateQuantity. The rateQuantity approach requires systems to have the capability to parse UCUM grammer where ml/hour is included rather than a specific ratio where the time is specified as the denominator. Where a rate such as 500ml over 2 hours is specified, the use of rateRatio may be more semantically correct than specifying using a rateQuantity of 250 mg/hour.
Cardinality 0..1
Type Ratio, Range, Quantity(SimpleQuantity)
Invariants ele-1

MedicationStatement.dosage.maxDosePerPeriod

Short Upper limit on medication per unit of time
Definition Upper limit on medication per unit of time.
Requirements The maximum total quantity of a therapeutic substance that may be administered to a subject over the period of time. For example, 1000mg in 24 hours.
Comments This is intended for use as an adjunct to the dosage when there is an upper cap. For example "2 tablets every 4 hours to a maximum of 8/day".
Cardinality 0..1
Type Ratio
Invariants ele-1

MedicationStatement.dosage.maxDosePerAdministration

Short Upper limit on medication per administration
Definition Upper limit on medication per administration.
Requirements The maximum total quantity of a therapeutic substance that may be administered to a subject per administration.
Comments This is intended for use as an adjunct to the dosage when there is an upper cap. For example, a body surface area related dose with a maximum amount, such as 1.5 mg/m2 (maximum 2 mg) IV over 5 – 10 minutes would have doseQuantity of 1.5 mg/m2 and maxDosePerAdministration of 2 mg.
Cardinality 0..1
Type Quantity(SimpleQuantity)
Invariants ele-1

MedicationStatement.dosage.maxDosePerLifetime

Short Upper limit on medication per lifetime of the patient
Definition Upper limit on medication per lifetime of the patient.
Requirements The maximum total quantity of a therapeutic substance that may be administered per lifetime of the subject.
Cardinality 0..1
Type Quantity(SimpleQuantity)
Invariants ele-1