The IMDRF (International Medical Device Regulators Forum), an international cooperation body promoting the harmonisation of medical device regulation, published on March 3, 2025, a new version of the codes for reporting adverse events associated with the use of Medical Devices.
The document, entitled ‘IMDRF Terminologies for Categorised Adverse Event Reporting (AER): Terms, Definitions and Codes’ (edition 2025-03-03), introduces new terms and codes to improve the classification and understanding of adverse events related to device safety.
The main purpose of this harmonisation, promoted by the IMDRF at a global level, is to improve the effectiveness of safety signal detection for both regulators and the medical device industry. Harmonisation aims to strengthen post-market surveillance (PMS) activities. The adoption of standardised terminology reduces ambiguity and increases the effectiveness of the adverse event investigation process.
Thanks to harmonised terminology, it is possible to classify adverse events associated with Medical Devices, such as:
- Malfunction
- Errors of use
- System faults
- Clinical complications
- Unintentional adverse reactions
- Other events that have resulted or could have resulted in serious damage to the health of the patient or the operator.
In the regulatory context, an ‘adverse event’ is any adverse or unexpected effect related to the use of a medical device, while an ‘accident’ is an event that caused or could have caused death or a serious deterioration in health.
The objective is twofold:
- Facilitating global data collection, analysis and sharing.
- Simplify the compilation of documents such as the Manufacturer Incident Report (MIR) used in the European Union and similar forms provided by regulatory authorities in other countries.
What the new version envisages (2025-03-03)
The update introduced 36 new terms, modified 56 existing entries and withdrew 8 terms.
The new edition updates six code groups:
- Device Problem Terms
- Terms for the type of clinical event (Clinical Signs, Symptoms and Conditions)
- Terms relating to Patient Outcome
- Root Cause Terms
- Terms related to the device component involved (Component Terms)
- Human Factors Terms
Each term is accompanied by a code and a clear definition. Some examples of new codes in the Device Problem Terms category:
- D1.8471 – Unexpected activation
- D1.8472 – Improper fitting
Each code can be used in corporate information systems to consistently label, store and analyse incident reports.
Implications for Manufacturers
The adoption of the new terminology is recommended internationally, but is not yet mandatory in the European Union.
However, the European MIR form, which manufacturers must fill out in the event of a serious accident or corrective action, is built on the basis of the IMDRF structure. This means that it is very likely that the EU will transpose the new versions, as has already happened in the past. As far as the European Union is concerned, in the event of adoption, a transition period of at least one year from the publication of the possible new MIR form is envisaged, as in the past.
Therefore, manufacturers should monitor regulatory developments in their country and then coordinate with post-market surveillance (PMS) managers to ensure compliance and consistency in adverse event reporting.
The IMDRF provides an annual process through which stakeholders can request changes to the AET terminology. Requests for changes can be submitted from September 1 of the current year to September 1 of the following year. Accepted changes are published in March, along with a log (Change Log) detailing each request and the reason for acceptance or rejection.
Conclusion
The adoption of a common terminology at a global level is an essential step to ensure greater transparency, comparability and safety in the use of Medical Devices. Manufacturers are encouraged to monitor updates to prepare for changes.
>>> Thema experts follow all developments in the application of the guideline in different countries around the world and can provide comprehensive assistance in the management of the post-market marketing of Medical Devices.
04/15/2025
