What does clinical evaluation under EU MDR really require?
MDR Annex XIV · Article 61 · MDCG 2020-6 Rev 2
The short answer
Clinical evaluation is a continuous, systematic process — not a one-time pre-market activity. It is required for all device classes, governed by Annex XIV of MDR, and must be documented in a Clinical Evaluation Report (CER). It is the most common area of NB audit findings under MDR.
What clinical evaluation IS and IS NOT
What it IS
- A continuous lifecycle process
- Systematic appraisal of clinical data
- Assessment of benefit-risk profile
- Documented in the CER
- Feeds into PSUR and PMS updates
- Required for all device classes (including Class I)
What it IS NOT
- A one-time pre-submission document
- Just a literature review
- Only required if you ran a clinical study
- The same as a clinical investigation
- Automatically satisfied by FDA clinical data alone
- Something that can remain static after CE marking
The clinical evaluation process (Annex XIV)
- Define scope and intended purpose: Identify the device, indications, target population, clinical claims
- Identify and appraise clinical data: Literature search (systematic), clinical investigations, PMS/PMCF data, vigilance data
- Analyse clinical data: Assess safety and performance against the GSPR, demonstrate benefit-risk is acceptable
- Write the CER: Document all of the above; include conclusions and any remaining uncertainties
- Establish PMCF: Plan for ongoing post-market clinical data collection to address gaps and update the CER
Equivalence — much harder under MDR than MDD
If you rely on clinical data from an equivalent device (a common strategy under MDD), MDR Annex XIV Part A Section 3 requires you to demonstrate equivalence across three dimensions simultaneously:
- Technical equivalence: Same design, same materials, same specifications, same deployment method
- Biological equivalence: Same materials in contact with human body, same tissues/body fluids in contact
- Clinical equivalence: Same intended purpose, same clinical conditions, same site of use, same user population
For Class III and implantable Class IIb devices, equivalence must be demonstrated through a contract with the owner of the equivalent device granting access to their technical documentation. This is rarely achievable if the equivalent device belongs to a competitor.
CER update frequency
| Device class | CER update requirement |
|---|---|
| Class IIb / Class III | Annually (aligned with PSUR cycle) |
| Class IIa | At least every 2 years (aligned with PSUR cycle) |
| Class I | No formal PSUR cycle; update when clinically relevant new data is available |
Even between formal updates, the CER must be reviewed if significant new clinical data is available — such as a signal from PMS, a literature report, or a serious incident.
When is a clinical investigation required?
Clinical investigations (prospective studies on human subjects) are generally required for:
- Class III devices (Article 61(4)) — unless exception applies
- Implantable Class IIb devices (Article 61(4))
- Any device where existing clinical data is insufficient to demonstrate conformity with GSPR
- Novel technologies, novel intended purposes, or where no equivalent device exists
Exceptions exist but are narrowly defined. A NB or the competent authority may require a clinical investigation even where the manufacturer believes existing data is sufficient.
Frequently asked questions
What is the difference between a CER and a clinical investigation?
The Clinical Evaluation Report (CER) is a document that appraises all available clinical data. A clinical investigation is a prospective study that generates new clinical data. The CER may incorporate data from clinical investigations, but a CER is not itself a clinical investigation.
Can I use the equivalence route for my Class III device?
Only if you have a contract with the equivalent device's owner giving you access to their full technical documentation (Article 61(5)). In practice, this rules out using a competitor's device as equivalent for Class III. Own-device equivalence is possible if you have previously placed an identical or near-identical device on the market.
Does Class I need a clinical evaluation?
Yes. All device classes require clinical evaluation. For Class I, the depth of evidence required is proportionate to risk, but the process and documentation obligation (CER) still apply.