Implementation Guide
Health Device Data Transfer
Version 0.1.0 - ballot

Specification of health data transfer from devices to DiGA (§ 374a SGB V)

Resource Profile: HddtSensorTypeAndCalibrationStatus - XML Profile

Draft as of 2025-10-27

XML representation of the hddt-sensor-type-and-calibration-status resource profile.

Raw xml | Download


<StructureDefinition xmlns="http://hl7.org/fhir">
  <id value="hddt-sensor-type-and-calibration-status"/>
  <text>
    <status value="extensions"/>
    <div xmlns="http://www.w3.org/1999/xhtml"><p class="res-header-id"><b>Generated Narrative: StructureDefinition hddt-sensor-type-and-calibration-status</b></p><a name="hddt-sensor-type-and-calibration-status"> </a><a name="hchddt-sensor-type-and-calibration-status"> </a><table border="0" cellpadding="0" cellspacing="0" style="border: 0px #F0F0F0 solid; font-size: 11px; font-family: verdana; vertical-align: top;"><tr style="border: 1px #F0F0F0 solid; font-size: 11px; font-family: verdana; vertical-align: top"><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="The logical name of the element">Name</a></th><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Information about the use of the element">Flags</a></th><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Minimum and Maximum # of times the element can appear in the instance">Card.</a></th><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px; width: 100px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Reference to the type of the element">Type</a></th><th style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; padding-top: 3px; padding-bottom: 3px" class="hierarchy"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Additional information about the element">Description &amp; Constraints</a><span style="float: right"><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Legend for this format"><img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3goXBCwdPqAP0wAAAldJREFUOMuNk0tIlFEYhp9z/vE2jHkhxXA0zJCMitrUQlq4lnSltEqCFhFG2MJFhIvIFpkEWaTQqjaWZRkp0g26URZkTpbaaOJkDqk10szoODP//7XIMUe0elcfnPd9zsfLOYplGrpRwZaqTtw3K7PtGem7Q6FoidbGgqHVy/HRb669R+56zx7eRV1L31JGxYbBtjKK93cxeqfyQHbehkZbUkK20goELEuIzEd+dHS+qz/Y8PTSif0FnGkbiwcAjHaU1+QWOptFiyCLp/LnKptpqIuXHx6rbR26kJcBX3yLgBfnd7CxwJmflpP2wUg0HIAoUUpZBmKzELGWcN8nAr6Gpu7tLU/CkwAaoKTWRSQyt89Q8w6J+oVQkKnBoblH7V0PPvUOvDYXfopE/SJmALsxnVm6LbkotrUtNowMeIrVrBcBpaMmdS0j9df7abpSuy7HWehwJdt1lhVwi/J58U5beXGAF6c3UXLycw1wdFklArBn87xdh0ZsZtArghBdAA3+OEDVubG4UEzP6x1FOWneHh2VDAHBAt80IbdXDcesNoCvs3E5AFyNSU5nbrDPZpcUEQQTFZiEVx+51fxMhhyJEAgvlriadIJZZksRuwBYMOPBbO3hePVVqgEJhFeUuFLhIPkRP6BQLIBrmMenujm/3g4zc398awIe90Zb5A1vREALqneMcYgP/xVQWlG+Ncu5vgwwlaUNx+3799rfe96u9K0JSDXcOzOTJg4B6IgmXfsygc7/Bvg9g9E58/cDVmGIBOP/zT8Bz1zqWqpbXIsd0O9hajXfL6u4BaOS6SeWAAAAAElFTkSuQmCC" alt="doco" style="background-color: inherit"/></a></span></th></tr><tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck1.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_resource.png" alt="." style="background-color: white; background-color: inherit" title="Resource" class="hierarchy"/> <a href="StructureDefinition-hddt-sensor-type-and-calibration-status-definitions.html#DeviceMetric" title="Describes the sensor type and calibration status of a sensor within a Personal Health Device as a DeviceMetric.">DeviceMetric</a><a name="DeviceMetric"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">0</span><span style="opacity: 0.5">..</span><span style="opacity: 0.5">*</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a href="http://hl7.org/fhir/R4/devicemetric.html">DeviceMetric</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">Configuration or setting capability of a personal health device</td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: #F7F7F7"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck10.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_element.gif" alt="." style="background-color: #F7F7F7; background-color: inherit" title="Element" class="hierarchy"/> <a href="StructureDefinition-hddt-sensor-type-and-calibration-status-definitions.html#DeviceMetric.unit" title="The unit in which the Personal Health Device presents its measurement values to the patient.">unit</a><a name="DeviceMetric.unit"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">0</span><span style="opacity: 0.5">..</span><span style="opacity: 0.5">1</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a style="opacity: 0.5; opacity: 0.5" href="http://hl7.org/fhir/R4/datatypes.html#CodeableConcept">CodeableConcept</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">UCUM code of the unit of the measurement as it is used when presenting data to the patient<br class="binding"/><span style="font-weight:bold" title="null" class="binding">Binding: </span><a href="http://hl7.org/fhir/R4/valueset-ucum-units.html" title="http://hl7.org/fhir/ValueSet/ucum-units" class="binding">UCUMCodes</a><span title="null" class="binding"> (</span><a href="http://hl7.org/fhir/R4/terminologies.html#required" title="To be conformant, the concept in this element SHALL be from the specified value set." class="binding">required</a><span title="null" class="binding">)</span><span title="null" class="binding">: </span><span title="null" class="binding">For HDDT only codes from UCUM MUST be used for coding units of measurements</span></td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck10.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_reference.png" alt="." style="background-color: white; background-color: inherit" title="Reference to another Resource" class="hierarchy"/> <a href="StructureDefinition-hddt-sensor-type-and-calibration-status-definitions.html#DeviceMetric.source" title="Points to the specific Device resource that holds the sensor for which the documented calibration status applies.">source</a><a name="DeviceMetric.source"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">1..<span style="opacity: 0.5">1</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a href="http://hl7.org/fhir/R4/references.html">Reference</a>(<a href="StructureDefinition-hddt-personal-health-device.html">Device – Personal Health Device</a>)</td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">Reference to the Personal Health Device holding the sensor</td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: #F7F7F7"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck10.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_element.gif" alt="." style="background-color: #F7F7F7; background-color: inherit" title="Element" class="hierarchy"/> <a href="StructureDefinition-hddt-sensor-type-and-calibration-status-definitions.html#DeviceMetric.operationalStatus">operationalStatus</a><a name="DeviceMetric.operationalStatus"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">0</span><span style="opacity: 0.5">..</span><span style="opacity: 0.5">1</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a style="opacity: 0.5; opacity: 0.5" href="http://hl7.org/fhir/R4/datatypes.html#code">code</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">on | off | standby | entered-in-error</span></td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck01.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin_end.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_element.gif" alt="." style="background-color: white; background-color: inherit" title="Element" class="hierarchy"/> <a href="StructureDefinition-hddt-sensor-type-and-calibration-status-definitions.html#DeviceMetric.calibration">calibration</a><a name="DeviceMetric.calibration"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="padding-left: 3px; padding-right: 3px; color: white; background-color: red" title="This element must be supported">S</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">0</span><span style="opacity: 0.5">..</span><span style="opacity: 0.5">*</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a style="opacity: 0.5; opacity: 0.5" href="http://hl7.org/fhir/R4/datatypes.html#BackboneElement">BackboneElement</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">Describes the calibrations that have been performed or that are required to be performed</span></td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: #F7F7F7"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck010.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_blank.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_element.gif" alt="." style="background-color: #F7F7F7; background-color: inherit" title="Element" class="hierarchy"/> <a href="StructureDefinition-hddt-sensor-type-and-calibration-status-definitions.html#DeviceMetric.calibration.state">state</a><a name="DeviceMetric.calibration.state"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"/><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">1..<span style="opacity: 0.5">1</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a style="opacity: 0.5; opacity: 0.5" href="http://hl7.org/fhir/R4/datatypes.html#code">code</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: #F7F7F7; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">not-calibrated | calibration-required | calibrated | unspecified</span></td></tr>
<tr style="border: 0px #F0F0F0 solid; padding:0px; vertical-align: top; background-color: white"><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px; white-space: nowrap; background-image: url(tbl_bck000.png)" class="hierarchy"><img src="tbl_spacer.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_blank.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="tbl_vjoin_end.png" alt="." style="background-color: inherit" class="hierarchy"/><img src="icon_element.gif" alt="." style="background-color: white; background-color: inherit" title="Element" class="hierarchy"/> <a href="StructureDefinition-hddt-sensor-type-and-calibration-status-definitions.html#DeviceMetric.calibration.time" title="The time when the last calibration has been performed. This element covers both manual calibration performed 
by the patient and automated calibration performed by the device itself. E.g. with a self-calibrating rtCGM `calibration.time`
signals the time when the device started sending calibrated values after the initial calibration phase. 

If the sensor does not require calibration, this element MAY be omitted. ">time</a><a name="DeviceMetric.calibration.time"> </a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="padding-left: 3px; padding-right: 3px; color: white; background-color: red" title="This element must be supported">S</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><span style="opacity: 0.5">0</span><span style="opacity: 0.5">..</span><span style="opacity: 0.5">1</span></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy"><a style="opacity: 0.5; opacity: 0.5" href="http://hl7.org/fhir/R4/datatypes.html#instant">instant</a></td><td style="vertical-align: top; text-align : var(--ig-left,left); background-color: white; border: 0px #F0F0F0 solid; padding:0px 4px 0px 4px" class="hierarchy">Time when the last calibration has been performed</td></tr>
<tr><td colspan="5" class="hierarchy"><br/><a href="https://build.fhir.org/ig/FHIR/ig-guidance/readingIgs.html#table-views" title="Legend for this format"><img src="data:image/png;base64,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" alt="doco" style="background-color: inherit"/> Documentation for this format</a></td></tr></table></div>
  </text>
  <url
       value="https://gematik.de/fhir/hddt/StructureDefinition/hddt-sensor-type-and-calibration-status"/>
  <version value="0.1.0"/>
  <name value="HddtSensorTypeAndCalibrationStatus"/>
  <title value="DeviceMetric – Sensor Type and Calibration Status"/>
  <status value="draft"/>
  <date value="2025-10-27"/>
  <publisher value="gematik GmbH"/>
  <description
               value="The HddtSensorTypeAndCalibrationStatus profile captures the calibration status of a sensor which is part of a Personal Health Device. 

Personal Health Devices need to be calibrated in order to provide safe measurements. Some devices are already calibrated by the 
manufacturer while others calibrate themselves after activation and others need to be calibrated by the patient. 
If a Personal Health Device transmits data from a non calibrated sensor to the resource server at all depends on the concrete product. 
For a DiGA as a device data consumer to process device data in a safe manner, it must be transparent if the data it received was 
measured by a calibrated sensor or not. 

For devices where the sensor that measured a value requires automated or manual calibration, the Observation capturing this value 
MUST refer to a HddtSensorTypeAndCalibrationStatus resource through its `Observation.device` element. 
The HddtSensorTypeAndCalibrationStatus implements a FHIR [DeviceMetric](https://hl7.org/fhir/R4/devicemetric.html) resource which 
holds calibration information in a `calibration.type`, a `calibration.state` and a `calibration.date` element. In addition 
the HddtSensorTypeAndCalibrationStatus can provide a definition of the `unit` that is preferrably to be used for presenting 
measured values to the patient. 

The HddtSensorTypeAndCalibrationStatus of a measurement MUST always refer to a HddTPersonalHealthDevice [Device](https://hl7.org/fhir/R4/device.html) resource that represents the 
Personal Health Device that contains the sensor. This is a many-to-one relationship which allows for a Personal Health Device to 
contain multiple sensors for different measured values. E.g. by this a pulse oximeter as a HDDT Personal Health Device can 
provide _pulse_ and _SPO2_ as two different interoperable values with each of this values being linked with a 
dedicated HddtSensorTypeAndCalibrationStatus resource. 

**Obligations and Conventions:**

DiGA as device data consumers SHOULD NOT rely on the `DeviceMetric.operationalStatus` of a sensor as this status does only reflect the status of the sensor 
and does not provide information about the end-to-end status of the flow of device data from the sensor within the Personal Health Device 
to the resource server in the device backend. Instead DiGA SHOULD process the `Device.status` information that can be obtained through the 
`DeviceMetric.source` reference. This element considers the end-to-end availability of data and therefore is the only source for 
information about potentially missing data (e.g. due to temporal problems with the bluetooth or internet connection).

**Constraints applied:**  
- `unit` is restricted to UCUM. 
- `source` is constrained as a mandatory element in order to enable a DiGA to obtain dynamic and static device attributes through this reference
- `calibration` is set to _Must Support_. This element and respective status information MUST be provided if the sensor performs automated or requires manual calibration after the device has been put into operation with the patient (`Device.status`is `active`)."/>
  <copyright value="Copyright (c) 2025 gematik GmbH"/>
  <fhirVersion value="4.0.1"/>
  <mapping>
    <identity value="w5"/>
    <uri value="http://hl7.org/fhir/fivews"/>
    <name value="FiveWs Pattern Mapping"/>
  </mapping>
  <mapping>
    <identity value="rim"/>
    <uri value="http://hl7.org/v3"/>
    <name value="RIM Mapping"/>
  </mapping>
  <kind value="resource"/>
  <abstract value="false"/>
  <type value="DeviceMetric"/>
  <baseDefinition
                  value="http://hl7.org/fhir/StructureDefinition/DeviceMetric"/>
  <derivation value="constraint"/>
  <snapshot>
    <extension
               url="http://hl7.org/fhir/tools/StructureDefinition/snapshot-base-version">
      <valueString value="4.0.1"/>
    </extension>
    <element id="DeviceMetric">
      <path value="DeviceMetric"/>
      <short
             value="Configuration or setting capability of a personal health device"/>
      <definition
                  value="Describes the sensor type and calibration status of a sensor within a Personal Health Device as a DeviceMetric."/>
      <comment
               value="For the initial scope, this DeviceMetric resource is only applicable to describe a single metric node in the containment tree that is produced by the context scanner in any medical device that implements or derives from the ISO/IEEE 11073 standard."/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="DeviceMetric"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <constraint>
        <key value="dom-2"/>
        <severity value="error"/>
        <human
               value="If the resource is contained in another resource, it SHALL NOT contain nested Resources"/>
        <expression value="contained.contained.empty()"/>
        <xpath value="not(parent::f:contained and f:contained)"/>
        <source
                value="http://hl7.org/fhir/StructureDefinition/DomainResource"/>
      </constraint>
      <constraint>
        <key value="dom-3"/>
        <severity value="error"/>
        <human
               value="If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource"/>
        <expression
                    value="contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()"/>
        <xpath
               value="not(exists(for $id in f:contained/*/f:id/@value return $contained[not(parent::*/descendant::f:reference/@value=concat('#', $contained/*/id/@value) or descendant::f:reference[@value='#'])]))"/>
        <source
                value="http://hl7.org/fhir/StructureDefinition/DomainResource"/>
      </constraint>
      <constraint>
        <key value="dom-4"/>
        <severity value="error"/>
        <human
               value="If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated"/>
        <expression
                    value="contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()"/>
        <xpath
               value="not(exists(f:contained/*/f:meta/f:versionId)) and not(exists(f:contained/*/f:meta/f:lastUpdated))"/>
        <source
                value="http://hl7.org/fhir/StructureDefinition/DomainResource"/>
      </constraint>
      <constraint>
        <key value="dom-5"/>
        <severity value="error"/>
        <human
               value="If a resource is contained in another resource, it SHALL NOT have a security label"/>
        <expression value="contained.meta.security.empty()"/>
        <xpath value="not(exists(f:contained/*/f:meta/f:security))"/>
        <source
                value="http://hl7.org/fhir/StructureDefinition/DomainResource"/>
      </constraint>
      <constraint>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bestpractice">
          <valueBoolean value="true"/>
        </extension>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bestpractice-explanation">
          <valueMarkdown
                         value="When a resource has no narrative, only systems that fully understand the data can display the resource to a human safely. Including a human readable representation in the resource makes for a much more robust eco-system and cheaper handling of resources by intermediary systems. Some ecosystems restrict distribution of resources to only those systems that do fully understand the resources, and as a consequence implementers may believe that the narrative is superfluous. However experience shows that such eco-systems often open up to new participants over time."/>
        </extension>
        <key value="dom-6"/>
        <severity value="warning"/>
        <human
               value="A resource should have narrative for robust management"/>
        <expression value="text.`div`.exists()"/>
        <xpath value="exists(f:text/h:div)"/>
        <source
                value="http://hl7.org/fhir/StructureDefinition/DomainResource"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="Entity. Role, or Act"/>
      </mapping>
    </element>
    <element id="DeviceMetric.id">
      <path value="DeviceMetric.id"/>
      <short value="Logical id of this artifact"/>
      <definition
                  value="The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes."/>
      <comment
               value="The only time that a resource does not have an id is when it is being submitted to the server using a create operation."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Resource.id"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="id"/>
        </extension>
        <code value="http://hl7.org/fhirpath/System.String"/>
      </type>
      <isModifier value="false"/>
      <isSummary value="true"/>
    </element>
    <element id="DeviceMetric.meta">
      <path value="DeviceMetric.meta"/>
      <short value="Metadata about the resource"/>
      <definition
                  value="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."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Resource.meta"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="Meta"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
    </element>
    <element id="DeviceMetric.implicitRules">
      <path value="DeviceMetric.implicitRules"/>
      <short value="A set of rules under which this content was created"/>
      <definition
                  value="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."/>
      <comment
               value="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."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Resource.implicitRules"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="uri"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="true"/>
      <isModifierReason
                        value="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"/>
      <isSummary value="true"/>
    </element>
    <element id="DeviceMetric.language">
      <path value="DeviceMetric.language"/>
      <short value="Language of the resource content"/>
      <definition
                  value="The base language in which the resource is written."/>
      <comment
               value="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)."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Resource.language"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="code"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <binding>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-maxValueSet">
          <valueCanonical value="http://hl7.org/fhir/ValueSet/all-languages"/>
        </extension>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="Language"/>
        </extension>
        <strength value="preferred"/>
        <description value="A human language."/>
        <valueSet value="http://hl7.org/fhir/ValueSet/languages|4.0.1"/>
      </binding>
    </element>
    <element id="DeviceMetric.text">
      <path value="DeviceMetric.text"/>
      <short value="Text summary of the resource, for human interpretation"/>
      <definition
                  value="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 &quot;clinically safe&quot; for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety."/>
      <comment
               value="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 &quot;text blob&quot; or where text is additionally entered raw or narrated and encoded information is added later."/>
      <alias value="narrative"/>
      <alias value="html"/>
      <alias value="xhtml"/>
      <alias value="display"/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="DomainResource.text"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="Narrative"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="Act.text?"/>
      </mapping>
    </element>
    <element id="DeviceMetric.contained">
      <path value="DeviceMetric.contained"/>
      <short value="Contained, inline Resources"/>
      <definition
                  value="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."/>
      <comment
               value="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."/>
      <alias value="inline resources"/>
      <alias value="anonymous resources"/>
      <alias value="contained resources"/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="DomainResource.contained"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Resource"/>
      </type>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="N/A"/>
      </mapping>
    </element>
    <element id="DeviceMetric.extension">
      <path value="DeviceMetric.extension"/>
      <short value="Additional content defined by implementations"/>
      <definition
                  value="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."/>
      <comment
               value="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."/>
      <alias value="extensions"/>
      <alias value="user content"/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="DomainResource.extension"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Extension"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <constraint>
        <key value="ext-1"/>
        <severity value="error"/>
        <human value="Must have either extensions or value[x], not both"/>
        <expression value="extension.exists() != value.exists()"/>
        <xpath
               value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="N/A"/>
      </mapping>
    </element>
    <element id="DeviceMetric.modifierExtension">
      <path value="DeviceMetric.modifierExtension"/>
      <short value="Extensions that cannot be ignored"/>
      <definition
                  value="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)."/>
      <comment
               value="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."/>
      <requirements
                    value="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](http://hl7.org/fhir/R4/extensibility.html#modifierExtension)."/>
      <alias value="extensions"/>
      <alias value="user content"/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="DomainResource.modifierExtension"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Extension"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <constraint>
        <key value="ext-1"/>
        <severity value="error"/>
        <human value="Must have either extensions or value[x], not both"/>
        <expression value="extension.exists() != value.exists()"/>
        <xpath
               value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/>
      </constraint>
      <isModifier value="true"/>
      <isModifierReason
                        value="Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="N/A"/>
      </mapping>
    </element>
    <element id="DeviceMetric.identifier">
      <path value="DeviceMetric.identifier"/>
      <short value="Instance identifier"/>
      <definition
                  value="Unique instance identifiers assigned to a device by the device or gateway software, manufacturers, other organizations or owners. For example: handle ID."/>
      <comment
               value="For identifiers assigned to a device by the device or gateway software, the `system` element of the identifier should be set to the unique identifier of the device."/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="DeviceMetric.identifier"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Identifier"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
      <mapping>
        <identity value="w5"/>
        <map value="FiveWs.identifier"/>
      </mapping>
    </element>
    <element id="DeviceMetric.type">
      <path value="DeviceMetric.type"/>
      <short
             value="Identity of metric, for example Heart Rate or PEEP Setting"/>
      <definition
                  value="Describes the type of the metric. For example: Heart Rate, PEEP Setting, etc."/>
      <comment
               value="DeviceMetric.type can be referred to either IEEE 11073-10101 or LOINC."/>
      <min value="1"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.type"/>
        <min value="1"/>
        <max value="1"/>
      </base>
      <type>
        <code value="CodeableConcept"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
      <binding>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="MetricType"/>
        </extension>
        <strength value="preferred"/>
        <description value="Describes the metric type."/>
        <valueSet
                  value="http://hl7.org/fhir/ValueSet/devicemetric-type|4.0.1"/>
      </binding>
      <mapping>
        <identity value="w5"/>
        <map value="FiveWs.class"/>
      </mapping>
    </element>
    <element id="DeviceMetric.unit">
      <path value="DeviceMetric.unit"/>
      <short
             value="UCUM code of the unit of the measurement as it is used when presenting data to the patient"/>
      <definition
                  value="The unit in which the Personal Health Device presents its measurement values to the patient."/>
      <comment
               value="This element holds the unit of measurement that is preferrably to be used for presenting measured values to the patient. 
This unit MAY differ from the unit that is used with the `Observation.value[x]` of measured data.

_Example_: A rtCGM sensor measures glucose values as mg/dl. All data is stored in the health record in this unit. 
The resource server provides the data only using mg/dl as the unit. At the mobile app that came with the rtCGM (the rtCGM’s 
Personal Health Gateway) the patient configured the preferred unit as mmol/l. Therefore all data is calculated (by the device or 
the app) to mmol/l before displaying it to the patient. In this example the unit of `Observation.value[x]` is mg/dl 
while `DeviceMetric.unit` is mmol/l. The motivation for this behaviour is to allow the DiGA to obtain information about the 
patient’s preference and thus to be in sync with the medical aid by displaying measured values in the same unit."/>
      <requirements
                    value="allow a DiGA to detect the unit the patient is used to"/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.unit"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="CodeableConcept"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
      <binding>
        <strength value="required"/>
        <description
                     value="For HDDT only codes from UCUM MUST be used for coding units of measurements"/>
        <valueSet value="http://hl7.org/fhir/ValueSet/ucum-units"/>
      </binding>
    </element>
    <element id="DeviceMetric.source">
      <path value="DeviceMetric.source"/>
      <short
             value="Reference to the Personal Health Device holding the sensor"/>
      <definition
                  value="Points to the specific Device resource that holds the sensor for which the documented calibration status applies."/>
      <min value="1"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.source"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="Reference"/>
        <targetProfile
                       value="https://gematik.de/fhir/hddt/StructureDefinition/hddt-personal-health-device"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
    </element>
    <element id="DeviceMetric.parent">
      <path value="DeviceMetric.parent"/>
      <short value="Describes the link to the parent Device"/>
      <definition
                  value="Describes the link to the  Device that this DeviceMetric belongs to and that provide information about the location of this DeviceMetric in the containment structure of the parent Device. An example would be a Device that represents a Channel. This reference can be used by a client application to distinguish DeviceMetrics that have the same type, but should be interpreted based on their containment location."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.parent"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="Reference"/>
        <targetProfile
                       value="http://hl7.org/fhir/StructureDefinition/Device|4.0.1"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
    </element>
    <element id="DeviceMetric.operationalStatus">
      <path value="DeviceMetric.operationalStatus"/>
      <short value="on | off | standby | entered-in-error"/>
      <definition
                  value="Indicates current operational state of the device. For example: On, Off, Standby, etc."/>
      <comment
               value="DiGA as device data consumers SHOULD NOT rely on the `operationalStatus` of a sensor as this status does only reflect the status of the sensor 
and does not provide information about the end-to-end status of the flow of device data from the sensor within the Personal Health device 
to the resource server in the device backend. Instead DiGA SHOILD process the `Device.status` information that can be obtained through the 
`DeviceMetric.source` reference. This element considers the end-to-end availability of data and therefore is the only source for 
information about potentially missing data (e.g. due to temporal problems with the bluetooth or internet connection)."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.operationalStatus"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="code"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
      <binding>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="DeviceMetricOperationalStatus"/>
        </extension>
        <strength value="required"/>
        <description
                     value="Describes the operational status of the DeviceMetric."/>
        <valueSet
                  value="http://hl7.org/fhir/ValueSet/metric-operational-status|4.0.1"/>
      </binding>
    </element>
    <element id="DeviceMetric.color">
      <path value="DeviceMetric.color"/>
      <short
             value="black | red | green | yellow | blue | magenta | cyan | white"/>
      <definition
                  value="Describes the color representation for the metric. This is often used to aid clinicians to track and identify parameter types by color. In practice, consider a Patient Monitor that has ECG/HR and Pleth for example; the parameters are displayed in different characteristic colors, such as HR-blue, BP-green, and PR and SpO2- magenta."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.color"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="code"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
      <binding>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="DeviceMetricColor"/>
        </extension>
        <strength value="required"/>
        <description value="Describes the typical color of representation."/>
        <valueSet value="http://hl7.org/fhir/ValueSet/metric-color|4.0.1"/>
      </binding>
    </element>
    <element id="DeviceMetric.category">
      <path value="DeviceMetric.category"/>
      <short value="measurement | setting | calculation | unspecified"/>
      <definition
                  value="Indicates the category of the observation generation process. A DeviceMetric can be for example a setting, measurement, or calculation."/>
      <min value="1"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.category"/>
        <min value="1"/>
        <max value="1"/>
      </base>
      <type>
        <code value="code"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
      <binding>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="DeviceMetricCategory"/>
        </extension>
        <strength value="required"/>
        <description value="Describes the category of the metric."/>
        <valueSet value="http://hl7.org/fhir/ValueSet/metric-category|4.0.1"/>
      </binding>
      <mapping>
        <identity value="w5"/>
        <map value="FiveWs.class"/>
      </mapping>
    </element>
    <element id="DeviceMetric.measurementPeriod">
      <path value="DeviceMetric.measurementPeriod"/>
      <short value="Describes the measurement repetition time"/>
      <definition
                  value="Describes the measurement repetition time. This is not necessarily the same as the update period. The measurement repetition time can range from milliseconds up to hours. An example for a measurement repetition time in the range of milliseconds is the sampling rate of an ECG. An example for a measurement repetition time in the range of hours is a NIBP that is triggered automatically every hour. The update period may be different than the measurement repetition time, if the device does not update the published observed value with the same frequency as it was measured."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.measurementPeriod"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="Timing"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
    </element>
    <element id="DeviceMetric.calibration">
      <path value="DeviceMetric.calibration"/>
      <short
             value="Describes the calibrations that have been performed or that are required to be performed"/>
      <definition
                  value="Describes the calibrations that have been performed or that are required to be performed."/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="DeviceMetric.calibration"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="BackboneElement"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <mustSupport value="true"/>
      <isModifier value="false"/>
      <isSummary value="true"/>
    </element>
    <element id="DeviceMetric.calibration.id">
      <path value="DeviceMetric.calibration.id"/>
      <representation value="xmlAttr"/>
      <short value="Unique id for inter-element referencing"/>
      <definition
                  value="Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="Element.id"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/>
        </extension>
        <code value="http://hl7.org/fhirpath/System.String"/>
      </type>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="n/a"/>
      </mapping>
    </element>
    <element id="DeviceMetric.calibration.extension">
      <path value="DeviceMetric.calibration.extension"/>
      <short value="Additional content defined by implementations"/>
      <definition
                  value="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."/>
      <comment
               value="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."/>
      <alias value="extensions"/>
      <alias value="user content"/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="Element.extension"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Extension"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <constraint>
        <key value="ext-1"/>
        <severity value="error"/>
        <human value="Must have either extensions or value[x], not both"/>
        <expression value="extension.exists() != value.exists()"/>
        <xpath
               value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="false"/>
      <mapping>
        <identity value="rim"/>
        <map value="n/a"/>
      </mapping>
    </element>
    <element id="DeviceMetric.calibration.modifierExtension">
      <path value="DeviceMetric.calibration.modifierExtension"/>
      <short value="Extensions that cannot be ignored even if unrecognized"/>
      <definition
                  value="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)."/>
      <comment
               value="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."/>
      <requirements
                    value="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](http://hl7.org/fhir/R4/extensibility.html#modifierExtension)."/>
      <alias value="extensions"/>
      <alias value="user content"/>
      <alias value="modifiers"/>
      <min value="0"/>
      <max value="*"/>
      <base>
        <path value="BackboneElement.modifierExtension"/>
        <min value="0"/>
        <max value="*"/>
      </base>
      <type>
        <code value="Extension"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <constraint>
        <key value="ext-1"/>
        <severity value="error"/>
        <human value="Must have either extensions or value[x], not both"/>
        <expression value="extension.exists() != value.exists()"/>
        <xpath
               value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/>
      </constraint>
      <isModifier value="true"/>
      <isModifierReason
                        value="Modifier extensions are expected to modify the meaning or interpretation of the element that contains them"/>
      <isSummary value="true"/>
      <mapping>
        <identity value="rim"/>
        <map value="N/A"/>
      </mapping>
    </element>
    <element id="DeviceMetric.calibration.type">
      <path value="DeviceMetric.calibration.type"/>
      <short value="unspecified | offset | gain | two-point"/>
      <definition value="Describes the type of the calibration method."/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.calibration.type"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="code"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
      <binding>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="DeviceMetricCalibrationType"/>
        </extension>
        <strength value="required"/>
        <description value="Describes the type of a metric calibration."/>
        <valueSet
                  value="http://hl7.org/fhir/ValueSet/metric-calibration-type|4.0.1"/>
      </binding>
    </element>
    <element id="DeviceMetric.calibration.state">
      <path value="DeviceMetric.calibration.state"/>
      <short
             value="not-calibrated | calibration-required | calibrated | unspecified"/>
      <definition value="Describes the state of the calibration."/>
      <min value="1"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.calibration.state"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="code"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <isModifier value="false"/>
      <isSummary value="true"/>
      <binding>
        <extension
                   url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="DeviceMetricCalibrationState"/>
        </extension>
        <strength value="required"/>
        <description value="Describes the state of a metric calibration."/>
        <valueSet
                  value="http://hl7.org/fhir/ValueSet/metric-calibration-state|4.0.1"/>
      </binding>
    </element>
    <element id="DeviceMetric.calibration.time">
      <path value="DeviceMetric.calibration.time"/>
      <short value="Time when the last calibration has been performed"/>
      <definition
                  value="The time when the last calibration has been performed. This element covers both manual calibration performed 
by the patient and automated calibration performed by the device itself. E.g. with a self-calibrating rtCGM `calibration.time`
signals the time when the device started sending calibrated values after the initial calibration phase. 

If the sensor does not require calibration, this element MAY be omitted. "/>
      <min value="0"/>
      <max value="1"/>
      <base>
        <path value="DeviceMetric.calibration.time"/>
        <min value="0"/>
        <max value="1"/>
      </base>
      <type>
        <code value="instant"/>
      </type>
      <constraint>
        <key value="ele-1"/>
        <severity value="error"/>
        <human value="All FHIR elements must have a @value or children"/>
        <expression
                    value="hasValue() or (children().count() &gt; id.count())"/>
        <xpath value="@value|f:*|h:div"/>
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/>
      </constraint>
      <mustSupport value="true"/>
      <isModifier value="false"/>
      <isSummary value="true"/>
    </element>
  </snapshot>
  <differential>
    <element id="DeviceMetric">
      <path value="DeviceMetric"/>
      <short
             value="Configuration or setting capability of a personal health device"/>
      <definition
                  value="Describes the sensor type and calibration status of a sensor within a Personal Health Device as a DeviceMetric."/>
    </element>
    <element id="DeviceMetric.unit">
      <path value="DeviceMetric.unit"/>
      <short
             value="UCUM code of the unit of the measurement as it is used when presenting data to the patient"/>
      <definition
                  value="The unit in which the Personal Health Device presents its measurement values to the patient."/>
      <comment
               value="This element holds the unit of measurement that is preferrably to be used for presenting measured values to the patient. 
This unit MAY differ from the unit that is used with the `Observation.value[x]` of measured data.

_Example_: A rtCGM sensor measures glucose values as mg/dl. All data is stored in the health record in this unit. 
The resource server provides the data only using mg/dl as the unit. At the mobile app that came with the rtCGM (the rtCGM’s 
Personal Health Gateway) the patient configured the preferred unit as mmol/l. Therefore all data is calculated (by the device or 
the app) to mmol/l before displaying it to the patient. In this example the unit of `Observation.value[x]` is mg/dl 
while `DeviceMetric.unit` is mmol/l. The motivation for this behaviour is to allow the DiGA to obtain information about the 
patient’s preference and thus to be in sync with the medical aid by displaying measured values in the same unit."/>
      <requirements
                    value="allow a DiGA to detect the unit the patient is used to"/>
      <binding>
        <strength value="required"/>
        <description
                     value="For HDDT only codes from UCUM MUST be used for coding units of measurements"/>
        <valueSet value="http://hl7.org/fhir/ValueSet/ucum-units"/>
      </binding>
    </element>
    <element id="DeviceMetric.source">
      <path value="DeviceMetric.source"/>
      <short
             value="Reference to the Personal Health Device holding the sensor"/>
      <definition
                  value="Points to the specific Device resource that holds the sensor for which the documented calibration status applies."/>
      <min value="1"/>
      <type>
        <code value="Reference"/>
        <targetProfile
                       value="https://gematik.de/fhir/hddt/StructureDefinition/hddt-personal-health-device"/>
      </type>
    </element>
    <element id="DeviceMetric.operationalStatus">
      <path value="DeviceMetric.operationalStatus"/>
      <comment
               value="DiGA as device data consumers SHOULD NOT rely on the `operationalStatus` of a sensor as this status does only reflect the status of the sensor 
and does not provide information about the end-to-end status of the flow of device data from the sensor within the Personal Health device 
to the resource server in the device backend. Instead DiGA SHOILD process the `Device.status` information that can be obtained through the 
`DeviceMetric.source` reference. This element considers the end-to-end availability of data and therefore is the only source for 
information about potentially missing data (e.g. due to temporal problems with the bluetooth or internet connection)."/>
    </element>
    <element id="DeviceMetric.calibration">
      <path value="DeviceMetric.calibration"/>
      <mustSupport value="true"/>
    </element>
    <element id="DeviceMetric.calibration.state">
      <path value="DeviceMetric.calibration.state"/>
      <min value="1"/>
    </element>
    <element id="DeviceMetric.calibration.time">
      <path value="DeviceMetric.calibration.time"/>
      <short value="Time when the last calibration has been performed"/>
      <definition
                  value="The time when the last calibration has been performed. This element covers both manual calibration performed 
by the patient and automated calibration performed by the device itself. E.g. with a self-calibrating rtCGM `calibration.time`
signals the time when the device started sending calibrated values after the initial calibration phase. 

If the sensor does not require calibration, this element MAY be omitted. "/>
      <mustSupport value="true"/>
    </element>
  </differential>
</StructureDefinition>