AU Base Implementation Guide
4.1.0-ballot - CI Build AU

This page is part of AU Base v4.1.0 based on FHIR R4. For a full list of available versions, see the Directory of published versions

Data Type Profile: AUBaseDosage - Detailed Descriptions

Draft as of 2022-11-10 Maturity Level: 2

Definitions for the au-dosage data type profile.

1. Dosage
2. Dosage.additionalInstruction
BindingThe codes SHOULD be taken from SNOMEDCTAdditionalDosageInstructionsFor example codes, see SNOMEDCTAdditionalDosageInstructions
3. Dosage.asNeeded[x]
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/clinical-finding-1For example codes, see SNOMEDCTMedicationAsNeededReasonCodes
[x] NoteSee Choice of Data Types for further information about how to use [x]
4. Dosage.site
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/body-site-1For example codes, see SNOMEDCTAnatomicalStructureForAdministrationSiteCodes
5. Dosage.route
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/route-of-administration-1For example codes, see SNOMEDCTRouteCodes
6. Dosage.method
BindingThe codes SHOULD be taken from SNOMEDCTAdministrationMethodCodesFor example codes, see SNOMEDCTAdministrationMethodCodes
1. Dosage
Definition

Indicates how the medication is/was taken or should be taken by the patient.

Control0..*
InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
2. Dosage.modifierExtension
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).

Control0..*
TypeExtension
Is Modifiertrue
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.

Alternate Namesextensions, user content, modifiers
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
3. Dosage.additionalInstruction
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").

Control0..*
BindingThe codes SHOULD be taken from SNOMEDCTAdditionalDosageInstructionsFor example codes, see SNOMEDCTAdditionalDosageInstructions
TypeCodeableConcept
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
4. Dosage.asNeeded[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).

Control0..1
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/clinical-finding-1For example codes, see SNOMEDCTMedicationAsNeededReasonCodes
TypeChoice of: boolean, CodeableConcept
[x] NoteSee Choice of Data Types for further information about how to use [x]
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".

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
5. Dosage.site
Definition

Body site to administer to.

Control0..1
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/body-site-1For example codes, see SNOMEDCTAnatomicalStructureForAdministrationSiteCodes
TypeCodeableConcept
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
6. Dosage.route
Definition

How drug should enter body.

Control0..1
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/route-of-administration-1For example codes, see SNOMEDCTRouteCodes
TypeCodeableConcept
Requirements

A code specifying the route or physiological path of administration of a therapeutic agent into or onto a patient's body.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
7. Dosage.method
Definition

Technique for administering medication.

Control0..1
BindingThe codes SHOULD be taken from SNOMEDCTAdministrationMethodCodesFor example codes, see SNOMEDCTAdministrationMethodCodes
TypeCodeableConcept
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
1. Dosage
Definition

Indicates how the medication is/was taken or should be taken by the patient.

Control0..*
2. Dosage.id
Definition

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

Control0..1
Typestring
XML RepresentationIn the XML format, this property is represented as an attribute.
3. Dosage.extension
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.

Control0..*
TypeExtension
Alternate Namesextensionsuser content
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
SlicingThis element introduces a set of slices on Dosage.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
  • value @ url
4. Dosage.modifierExtension
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).

Control0..*
TypeExtension
Is Modifiertrue
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.

Alternate Namesextensionsuser contentmodifiers
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
5. Dosage.sequence
Definition

Indicates the order in which the dosage instructions should be applied or interpreted.

Control0..1
Typeinteger
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
6. Dosage.text
Definition

Free text dosage instructions e.g. SIG.

Control0..1
Typestring
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
7. Dosage.additionalInstruction
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").

Control0..*
BindingThe codes SHOULD be taken from SNOMEDCTAdditionalDosageInstructions
TypeCodeableConcept
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
8. Dosage.patientInstruction
Definition

Instructions in terms that are understood by the patient or consumer.

Control0..1
Typestring
InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
9. Dosage.timing
Definition

When medication should be administered.

Control0..1
TypeTiming
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
10. Dosage.asNeeded[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).

Control0..1
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/clinical-finding-1
TypeChoice of: boolean, CodeableConcept
[x] NoteSee Choice of Data Types for further information about how to use [x]
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".

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
11. Dosage.site
Definition

Body site to administer to.

Control0..1
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/body-site-1
TypeCodeableConcept
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
12. Dosage.route
Definition

How drug should enter body.

Control0..1
BindingThe codes SHOULD be taken from https://healthterminologies.gov.au/fhir/ValueSet/route-of-administration-1
TypeCodeableConcept
Requirements

A code specifying the route or physiological path of administration of a therapeutic agent into or onto a patient's body.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
13. Dosage.method
Definition

Technique for administering medication.

Control0..1
BindingThe codes SHOULD be taken from SNOMEDCTAdministrationMethodCodes
TypeCodeableConcept
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
14. Dosage.doseAndRate
Definition

The amount of medication administered.

Control0..*
TypeElement
InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
15. Dosage.doseAndRate.id
Definition

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

Control0..1
Typestring
XML RepresentationIn the XML format, this property is represented as an attribute.
16. Dosage.doseAndRate.extension
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.

Control0..*
TypeExtension
Alternate Namesextensionsuser content
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (: extension.exists() != value.exists())
SlicingThis element introduces a set of slices on Dosage.doseAndRate.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
  • value @ url
17. Dosage.doseAndRate.type
Definition

The kind of dose or rate specified, for example, ordered or calculated.

Control0..1
BindingFor example codes, see DoseAndRateType The kind of dose or rate specified
TypeCodeableConcept
Requirements

If the type is not populated, assume to be "ordered".

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
18. Dosage.doseAndRate.dose[x]
Definition

Amount of medication per dose.

Control0..1
TypeChoice of: Range, Quantity(SimpleQuantity)
[x] NoteSee Choice of Data Types for further information about how to use [x]
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
19. Dosage.doseAndRate.rate[x]
Definition

Amount of medication per unit of time.

Control0..1
TypeChoice of: Ratio, Range, Quantity(SimpleQuantity)
[x] NoteSee Choice of Data Types for further information about how to use [x]
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
20. Dosage.maxDosePerPeriod
Definition

Upper limit on medication per unit of time.

Control0..1
TypeRatio
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".

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
21. Dosage.maxDosePerAdministration
Definition

Upper limit on medication per administration.

Control0..1
TypeQuantity(SimpleQuantity)
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.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))
22. Dosage.maxDosePerLifetime
Definition

Upper limit on medication per lifetime of the patient.

Control0..1
TypeQuantity(SimpleQuantity)
Requirements

The maximum total quantity of a therapeutic substance that may be administered per lifetime of the subject.

InvariantsDefined on this element
ele-1: All FHIR elements must have a @value or children (: hasValue() or (children().count() > id.count()))