FHIR Extensions Pack
5.3.0 - May 2026 International flag

This page is part of the FHIR Core Extensions Registry (v5.3.0: Release 5.3) based on FHIR (HL7® FHIR® Standard) v5.0.0. This is the current published version. For a full list of available versions, see the Directory of published versions

Extension: Quantity Accuracy

Official URL: http://hl7.org/fhir/StructureDefinition/quantity-accuracy Version: 5.3.0
Standards status: Draft Maturity Level: 0 Responsible: HL7 International / Orders and Observations Computable Name: QuantityAccuracy

The absolute of the maximum deviation of the actual value from the reported value.

Accuracy is particularly applicable to measured or observed values. The reported observed value should be precise enough to reflect this accuracy, for example an observed value of 3.2 kg with an accuracy of 0.04 kg would be nonsensical. On the other hand, an observed value of 3.02 kg with an accuracy of 0.04 kg would indicate that the actual value is in the range of 3.02±0.04 kg or [2.98, 3.06] kg.

When applied to a DeviceMetric, it expresses the maximum deviation of values reported by the metric over the entire range of measurement.

Accuracy is usually in the same units as the reported value. Accuracy valueQuantity units SHOULD be provided for clarity; if omitted, they are implied to be the same as the reported value's units (or the DeviceMetric units).

This is an draft extension definition; the committee is seeking implementation feedback, and the definition or contents of the extension may change in future versions

Context of Use

This extension may be used on the following element(s)

Usage info

Usages:

  • This Extension is not used by any profiles in this Implementation Guide

You can also check for usages in the FHIR IG Statistics

Changes since version 5.2.0:

  • New Content

    • Formal Views of Extension Content

    Description of Profiles, Differentials, Snapshots, and how the XML and JSON presentations work.

    This structure is derived from Extension

    Summary

    Simple Extension with the type Quantity: The absolute of the maximum deviation of the actual value from the reported value.

    Accuracy is particularly applicable to measured or observed values. The reported observed value should be precise enough to reflect this accuracy, for example an observed value of 3.2 kg with an accuracy of 0.04 kg would be nonsensical. On the other hand, an observed value of 3.02 kg with an accuracy of 0.04 kg would indicate that the actual value is in the range of 3.02±0.04 kg or [2.98, 3.06] kg.

    When applied to a DeviceMetric, it expresses the maximum deviation of values reported by the metric over the entire range of measurement.

    Accuracy is usually in the same units as the reported value. Accuracy valueQuantity units SHOULD be provided for clarity; if omitted, they are implied to be the same as the reported value's units (or the DeviceMetric units).

    Maturity: 0

    This structure is derived from Extension

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. Extension 0..1 Extension Absolute maximum deviation from actual value
    ... extension 0..0 Extension
    ... url 1..1 uri "http://hl7.org/fhir/StructureDefinition/quantity-accuracy"
    ... value[x] 0..1 Quantity Absolute maximum deviation of the reported value from the actual value
    .... value 1..1 decimal Numerical value (with implicit precision)

    doco Documentation for this format
    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. Extension 0..1 Extension Absolute maximum deviation from actual value
    ... id 0..1 id Unique id for inter-element referencing
    ... extension 0..0 Extension
    Slice: Unordered, Open by value:url
    ... url 1..1 uri "http://hl7.org/fhir/StructureDefinition/quantity-accuracy"
    .... id 0..1 id Unique id for inter-element referencing
    .... extension 0..* Extension Additional content defined by implementations
    Slice: Unordered, Open by value:url
    .... value Σ 1..1 decimal Numerical value (with implicit precision)
    .... comparator ?!Σ 0..1 code < | <= | >= | > | ad - how to understand the value
    Binding: QuantityComparator (required): How the Quantity should be understood and represented.
    .... unit Σ 0..1 string Unit representation
    .... system ΣC 0..1 uri System that defines coded unit form
    .... code ΣC 0..1 code Coded form of the unit

    doco Documentation for this format

    This structure is derived from Extension

    Summary

    Simple Extension with the type Quantity: The absolute of the maximum deviation of the actual value from the reported value.

    Accuracy is particularly applicable to measured or observed values. The reported observed value should be precise enough to reflect this accuracy, for example an observed value of 3.2 kg with an accuracy of 0.04 kg would be nonsensical. On the other hand, an observed value of 3.02 kg with an accuracy of 0.04 kg would indicate that the actual value is in the range of 3.02±0.04 kg or [2.98, 3.06] kg.

    When applied to a DeviceMetric, it expresses the maximum deviation of values reported by the metric over the entire range of measurement.

    Accuracy is usually in the same units as the reported value. Accuracy valueQuantity units SHOULD be provided for clarity; if omitted, they are implied to be the same as the reported value's units (or the DeviceMetric units).

    Maturity: 0

    Differential View

    This structure is derived from Extension

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. Extension 0..1 Extension Absolute maximum deviation from actual value
    ... extension 0..0 Extension
    ... url 1..1 uri "http://hl7.org/fhir/StructureDefinition/quantity-accuracy"
    ... value[x] 0..1 Quantity Absolute maximum deviation of the reported value from the actual value
    .... value 1..1 decimal Numerical value (with implicit precision)

    doco Documentation for this format

    Snapshot View

    NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
    .. Extension 0..1 Extension Absolute maximum deviation from actual value
    ... id 0..1 id Unique id for inter-element referencing
    ... extension 0..0 Extension
    Slice: Unordered, Open by value:url
    ... url 1..1 uri "http://hl7.org/fhir/StructureDefinition/quantity-accuracy"
    .... id 0..1 id Unique id for inter-element referencing
    .... extension 0..* Extension Additional content defined by implementations
    Slice: Unordered, Open by value:url
    .... value Σ 1..1 decimal Numerical value (with implicit precision)
    .... comparator ?!Σ 0..1 code < | <= | >= | > | ad - how to understand the value
    Binding: QuantityComparator (required): How the Quantity should be understood and represented.
    .... unit Σ 0..1 string Unit representation
    .... system ΣC 0..1 uri System that defines coded unit form
    .... code ΣC 0..1 code Coded form of the unit

    doco Documentation for this format

     

    Other representations of profile: CSV, Excel, Schematron

    Terminology Bindings

    Path Status Usage ValueSet Version Source
    Extension.value[x].comparator Base required QuantityComparator 📍5.0.0 FHIR Std.

    Constraints

    Id Grade Path(s) Description Expression
    ele-1 error **ALL** elements All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
    ext-1 error **ALL** extensions Must have either extensions or value[x], not both extension.exists() != value.exists()

    R4B

    The extension is unchanged in R4B

    R4

    The extension is unchanged in R4

    R3

    The extension is unchanged in R3

    Search Parameters for this Extension

    (none found)