description: Profile for capturing the refence values as a FHIR Observation resource when evaluating lung function testings.\n\nThis profile defines the exchange of a single reference value for the Mandatory Interoperable Value (MIV) \\\"Lung Function Testing\\\" which is technically defined \nby the ValueSet _hddt-miv-lung-function-testing_. This MIV is e.g. implemented by peak flow meter that can connect to \na Personal Health Gateway (e.g. a mobile app for tracking lung function values) through wireless or wired communication.\n\n**Obligations and Conventions:**\n\nEach Lung Function Testing MAY either hold a reference to a _Sensor Type And Calibration Status_ [DeviceMetric](https://hl7.org/fhir/R4/devicemetric.html) resource or to a \n_Personal Health Device_ [Device](https://hl7.org/fhir/R4/device.html) resource (eXclusive OR). Typically the reference will be \nto a [Device](https://hl7.org/fhir/R4/device.html) resource, but the option to reference a [DeviceMetric](https://hl7.org/fhir/R4/devicemetric.html) \nresource is provided for compatibility with the overarching HDDT specification.\n\n**Constraints applied:**  \n- `code` is constrained to a subset of the _MIV Lung Function Reference Values_ ValueSet, defined by the _HddtLungFunctionReferenceValues_ ValueSet.\n- `effective[x]` is restricted to `effectivePeriod` and constrained as mandatory.\n- `value[x]` is restricted to `valueQuantity`. The elements `valueQuantity.value`, `valueQuantity.system`, and `valueQuantity.code` are constrained in a way that a value MUST be provided and that UCUM MUST be used for encoding the unit of measurement. `Observation.valueQuantity` MAY only be omitted in case of an error that accured with the measurement. In this case, `Observation.dataAbsentReason` MUST be provided.\n- `method` is considered mandatory in order to provide information about the method used to determine the reference value. It can be either a code from the _HddtLungFunctionReferenceValueMethod_ ValueSet or a text description.
package_name: de.gematik.hddt
derivation: constraint
name: HddtLungFunctionReferenceValue
type: Observation
elements:
  code:
    short: Reference measurement type for lung function
    binding: {strength: required, valueSet: 'https://gematik.de/fhir/hddt/ValueSet/hddt-lung-function-reference-values'}
    index: 0
  effective:
    short: Time period for which reference value is valid
    choices: [effectivePeriod]
    index: 2
  effectivePeriod: {type: Period, short: Time period for which reference value is valid, choiceOf: effective, index: 3}
  value:
    short: Reference lung function value
    mustSupport: true
    choices: [valueQuantity]
    index: 5
  valueQuantity: {type: Quantity, short: Reference lung function value, mustSupport: true, choiceOf: value, index: 6}
  value[x]:
    elements:
      value: {index: 7}
      system:
        pattern: {type: Uri, value: 'http://unitsofmeasure.org'}
        index: 8
      code:
        binding: {strength: required, valueSet: 'http://hl7.org/fhir/ValueSet/ucum-units'}
        index: 9
    required: [value, system, code]
  method:
    short: Method for determining the reference value
    mustSupport: true
    index: 10
    elements:
      coding:
        binding: {strength: required, valueSet: 'https://gematik.de/fhir/hddt/ValueSet/hddt-lung-function-reference-value-method-codes'}
        index: 11
      text: {index: 12}
  device:
    type: Reference
    short: Reference to personal health device
    refers: ['https://gematik.de/fhir/hddt/StructureDefinition/hddt-personal-health-device', 'https://gematik.de/fhir/hddt/StructureDefinition/hddt-sensor-type-and-calibration-status']
    index: 13
package_version: 1.0.1
class: profile
kind: resource
url: https://gematik.de/fhir/hddt/StructureDefinition/hddt-lung-reference-value
base: http://hl7.org/fhir/StructureDefinition/Observation
version: 1.0.1