New Guidance Released on EU MDR Vigilance Terms and Concepts

Mar 2, 2023 | News |

New Guidance Released on EU MDR Vigilance Terms and ConceptsThe EU Medical Device Coordination Group has recently released document MDCG 2023-3 titled “Questions and Answers on vigilance terms and concepts as outlined in the Regulation (EU) 2017/745 on medical devices.” Its goal is to help competent authorities, economic operators and other relevant parties better understand the vigilance requirements established in EU MDR 2017/745 Section 2 Chapter VII by clarifying terms and concepts. MDCG has taken a cue from another industry working group aiming to harmonize terminology for reporting adverse events related to medical devices.

In 2020, International Medical Device Regulators Forum published technical document “IMDRF terminologies for categorized Adverse Event Reporting (AER): terms, terminology structure and codes,” IMDRF/AE WG/N43. Both documents serve to improve effectiveness of the reporting process by reducing ambiguity, with slightly different clarifying approaches. While the MDCG guidance answers terminology questions to establish common understanding of the Regulation, the IMDRF technical document employs a coding structure to enable advanced incident management and evaluation of risks.

This MEDIcept Insight will highlight some of the important concepts clarified in the MDCG guidance document and discuss the ties between MDCG vigilance guidance and IMDRF’s Adverse Event Reporting categorization efforts.

MDCG 2023-3 – Questions and Answers on vigilance terms and concepts

The newly published MDCG guidance document uses a question-and-answer format to shed light on key vigilance terminology used in EU MDR 2017/745. Some of the crucial topics covered in the guidance are incidents and serious incidents, public health threats, user errors, undesirable side-effects. The scope does not include In Vitro Diagnostic Medical Devices Regulation (IVDR).

  • Incident vs. Serious Incident

All incidents should be documented and investigated but only serious incidents require reporting. The difference is in the severity of health or public health outcome, or potential outcome, related to an issue with a marketed device. Any malfunctions or deteriorations in characteristics or performance of a device constitutes an incident. A serious incident, and therefore a reportable event, is when a device issue leads to, or could potentially lead to, significant health or public health outcomes.  Significant health/ public health outcomes include death, serious temporary or permanent deterioration to the state of health of a patient, user or other persons, or a serious public health threat.

  • Serious public health threat

Instances when a device issue results in the possibility of multiple deaths occurring at short intervals or cause significant and unexpected events to occur such that they become alarming as a potential public health hazard. Some examples include widespread distribution of accidentally non-sterile devices, exposure to toxic compounds, high risk of exposure to a disease after use of the device.

  • Use-error, use-error due to ergonomic features, abnormal use

If a user’s action or inaction while using the device leads to an unexpected and unintended result, it is considered a use-error and is generally not considered an incident. The exception to this would be if the use-error was caused by a physical device feature designed to facilitate safe and effective use by the user, also called ergonomic features. Should an ergonomic feature cause a use-error that results in a serious incident, it is considered reportable.

Abnormal use is different than use-errors in that the user’s action or inaction deliberately violates the intended use of the device. Abnormal device use must be documented.

  • Undesirable side-effects

Normal use of the device that results in unintended and unwanted medical manifestation in the human body are considered undesirable side-effects and can be expected or unexpected. Expected side-effects should be clearly documented in the product information and considered in the manufacturer’s risk analysis. All undesirable side-effects are considered an incident. The results of device malfunction or deterioration in characteristics or performance do not constitute undesirable side-effects.

These terms are among many that are clarified in MDCG 2023-3 and contribute to a better over-all understanding of vigilance requirements within the EU.

Relation to IMDRF Categorized AER Efforts

The medical device industry is making strides in streamlining incident reporting processes to enable faster responses by regulatory authorities and device manufacturers alike. Working groups like MDCG and IMDRF are highlighting the importance of harmonizing terminology in the adverse event and reportable incident space. In similar fashion to IMDRF’s Adverse Event Reporting technical document, the MDCG document provides guidance on MDR vigilance terms and concepts. Standardizing the understanding and implementation of terminology is the cornerstone to IMDRF’s categorization of Adverse Event Reporting, which utilizes a terminology structure and code scheme.

Applying a code structure to categorize adverse events is intended to improve accuracy, reduce ambiguity and improve usability of incident management systems. Coding reportable events is only reliable if the definitions by which the events are categorized are widely understood. For this reason, the clarifications provided in MDCG 2023-3 are paramount to the implementation of IMDRF codes in the EU.

For more information on adverse event reporting and vigilance requirements, visit or email us at

For quick reference – a comprehensive list of questions addressed in MDCG 2023-3:

  1. What is the difference between an ‘incident’ and a ‘serious incident’ with a device under the MDR?
  2. What are the basic reporting criteria for a serious incident?
  3. How can incidents indirectly lead to a serious deterioration of health?
  4. With reference to Article 2(64) MDR, what is meant by a ‘malfunction or deterioration in the characteristics or performance of a device’?
  5. Who is considered as the ‘user’ of a device?
  6. What is a ‘use error’ in comparison to ‘abnormal use’?
  7. What is a ‘use-error due to ergonomic features’ as mentioned in Article 2(64) MDR?
  8. What is an ‘undesirable side-effect’ and how is it reported within the vigilance system?
  9. Article 87(5) MDR outlines the timelines for manufacturers to report an unanticipated serious deterioration in a person's state of health. When is a serious deterioration in a person's state of health considered ‘unanticipated’?
  10. With reference to the timelines for the reporting requirements outlined in Article 87 MDR, what is meant by ‘immediately’ and ‘without undue delay’?
  11. How to apply the reporting timelines defined by Article 87(3) to (5) MDR?
  12. With reference to the reporting timelines of a serious incident pursuant to Article 87 MDR, what is considered as the ‘manufacturer awareness date’?
  13. Why does the MIR in section 1.2(d) have a report type named ‘Final (Non-reportable incident)’ and when can it be used?
  14. What is a ‘field safety corrective action’?
  15. With reference to Article 87(1)(b) MDR, what is meant with ‘..including any field safety corrective action undertaken in a third country…’?
  16. Within the scope of Article 89 MDR on analysis of serious incidents and field safety corrective actions, what is an ‘evaluating competent authority’?
  17. Where can I find information on vigilance reporting in Eudamed?
  18. In accordance with Articles 10, 13 and 14 MDR, manufacturers, importers and distributors are required to inform competent authorities of devices that present or are considered to present a serious risk. What is meant by a ‘serious risk’?
  19. What is a ‘Periodic Summary Report’?
  20. What are the criteria for a ‘common and well documented’ serious incident?

Annexes of IMDRF AER Terminology technical document:

  1. Medical Device Problem
  2. Type of Investigation
  3. Investigation Findings
  4. Investigation Conclusion
  5. Health Effects – Clinical Signs and Symptoms or Conditions (Updated Feb. 2023)
  6. Health Effects – Health Impact
  7. Medical Device Component


Calia Harakaly – MEDIcept Associate Medical Device Consultant