DeviceMetric — Metric produced by a device

Describes what a device can measure, calculate or display: a monitor's heart rate, a pump's flow rate, a pulse oximeter's SpO2, a cuff's blood pressure. A device carries several DeviceMetric; each real measurement is an Observation referencing the DeviceMetric that produced it.

Purpose of the resource

Native medical-device interoperability (biomedical PnP) relies on two complementary standards: the IEEE 11073-10101 nomenclature (which codifies every measurement type with a stable, vendor-neutral numeric identifier), and the IEEE 11073-20701 SDC protocol (which describes how these measurements are exchanged on the network). DeviceMetric is the FHIR projection of the SDC Metric Description.

A DeviceMetric can be of category: measurement (value directly measured), calculation (value derived by an internal algorithm), setting (user-set value), unspecified. Typical cases: HR of a monitor, programmed flow rate of a pump, configured alarm.

Key fields

JSON example

"Heart rate" metric of a monitor, coded LOINC 8867-4 + IEEE 11073 147842, 1 Hz sampling, two-point calibration performed the day before:

{
  "resourceType": "DeviceMetric",
  "id": "monitor-heart-rate",
  "identifier": [{ "system": "http://acme.com/devices/metrics", "value": "HR-MON-12345" }],
  "type": {
    "coding": [{
      "system": "http://loinc.org",
      "code": "8867-4",
      "display": "Heart rate"
    }, {
      "system": "urn:iso:std:iso:11073:10101",
      "code": "147842",
      "display": "MDC_ECG_HEART_RATE"
    }]
  },
  "unit": {
    "coding": [{
      "system": "http://unitsofmeasure.org",
      "code": "/min",
      "display": "per minute"
    }]
  },
  "device": { "reference": "Device/example-monitor" },
  "operationalStatus": "on",
  "color": "red",
  "category": "measurement",
  "measurementFrequency": {
    "value": 1,
    "unit": "Hz",
    "system": "http://unitsofmeasure.org",
    "code": "Hz"
  },
  "calibration": [{
    "type": "two-point",
    "state": "calibrated",
    "time": "2026-05-15T08:00:00+02:00"
  }]
}

Typical use cases

• Multi-parameter monitoring: HR, SpO2, NIBP, RR, T°, ETCO2 — each one is a DeviceMetric.
• Infusion pumps: flow rate (mL/h), cumulative volume (mL), bolus, occlusion pressure.
• Ventilators: VT, FiO2, PEEP, RR, P-plateau, P-mean.
• Glucometers / CGM: continuous glucose, rate of change, alarms.
• IoMT platform: multi-device aggregation with a common MDC-code reference.

Common pitfalls

• Type without IEEE 11073 code: using LOINC alone breaks interop with SDC devices. Always provide at least one MDC code coding in parallel.
• Non-UCUM unit: "bpm" is not valid in UCUM — use /min.
• DeviceMetric / Observation confusion: DeviceMetric describes what the device can produce, Observation carries an actual measurement. Never embed a value in DeviceMetric.
• No calibration: for critical sensors (BIS, EtCO2, anaesthetic gases), calibration.time must be traced. Without calibration, measurements cannot be audited.
• Sampling frequency absent: for high-resolution waveforms (ECG 250 Hz, IBP 125 Hz), measurementFrequency is critical for rhythm analysis.

Related resources

• Device — parent device.
• DeviceDefinition — catalogue definition.
• Observation — every actual value references the DeviceMetric via device.
• DeviceUsage, DeviceAssociation — device usage.

See also: Device — physical instance and Observation — the actual measurement.