Overview
ISO 22077-1:2022 - "Health informatics - Medical waveform format - Part 1: Encoding rules" defines a general, interoperable encoding for medical waveform data (MFER: Medical Waveform Format Encoding Rules). The standard describes how time‑series physiological signals such as ECG, EEG, spirometry and other sampled waveforms are represented so healthcare information systems, databases and protocols can exchange and process them consistently. It is a format/encoding specification intended to be used alongside standards like HL7, DICOM® and the ISO/IEEE 11073 family.
Key technical topics and requirements
- Encoding model (TLV): Waveform headers and data use a Tag–Length–Value structure.
- Tag (T): includes class, primitive/context bit (P/C) and tag number; classes 0–2 are MFER standard coding and class 3 is for private use.
- Length (L): supports short (≤127 octets) and long (>127 octets) encodings.
- Value (V): carries the attribute definition or waveform data payload.
- Sampling attributes: two core sampling properties must be described - sampling rate (interval or frequency) and sampling resolution (LSB/quantization).
- Frame structure: a frame is the encoding unit and consists of data blocks, channels (individual waveform groups), and sequences (repetition/grouping of data blocks and channels).
- Definition levels: encoding and metadata are structured by levels (Basic rules - Level 1, Supplemental - Level 2, Extended - Level 3) to support minimal to rich descriptions.
- Human + machine readability: MFER supports coded fields for computer processing and text fields for human-readable descriptions.
- Out of scope: lower‑layer transport protocols and hard real‑time system behaviors (e.g., patient monitoring system network protocols) - these are implementation choices.
Practical applications and who uses it
- Device manufacturers: encode sampled waveform output (ECG, EEG, spirometry) for export and archival.
- EHR and PACS integrators: store and exchange waveform data consistently alongside DICOM images and HL7 messages.
- Clinical researchers & data scientists: obtain standardized waveform datasets for analytics and signal processing.
- Medical device software vendors & interoperability engineers: convert between proprietary waveform formats and MFER for interoperability.
- Clinical engineers & informaticians: implement conformance checks, database mappings, and data pipelines for waveform repositories.
Related standards (harmonization)
- Intended to be used with but does not replace or fully harmonize: DICOM®, HL7, ISO/IEEE 11073, SCP‑ECG, and other domain‑specific waveform specifications. ISO 22077‑1 focuses on encoding rules; specific waveform semantics and lower‑layer transport are addressed elsewhere.
Keywords: ISO 22077-1:2022, medical waveform format, MFER, encoding rules, TLV, sampling rate, ECG, EEG, waveform interoperability, health informatics.
