Clinical evaluation — overview
MDR Art. 61 and Annex XIV. Clinical evaluation is mandatory for all MDR devices regardless of class. It is a continuous, lifecycle process — not a one-time pre-market exercise.
This site provides general information only and does not constitute legal or regulatory advice. Always consult the official regulation text and a qualified regulatory professional.
What is clinical evaluation?
A clinical evaluation is a systematic, planned, and continuous process to generate, collect, analyse, and assess clinical data pertaining to a device in order to demonstrate and verify its safety, performance characteristics, and claimed clinical benefits when used in accordance with the manufacturer's instructions for use.
It is not simply a literature review. It is a structured scientific methodology that results in a Clinical Evaluation Report (CER) and feeds into the risk management file, technical documentation, and post-market activities.
Clinical evaluation is mandatory for all classes
MDR Art. 61(1) is unambiguous: clinical evaluation is required for all devices, irrespective of class. There is no "de minimis" exemption for simple Class I devices.
However, the depth and nature of the clinical evaluation scales with device risk:
| Class | Typical clinical evaluation approach |
|---|---|
| Class I | Literature-based; often brief; clinical investigation rarely needed |
| Class IIa | Literature + equivalence (where applicable) + some clinical data from PMS |
| Class IIb | Literature + substantial clinical data; equivalence heavily scrutinised |
| Class III | Full clinical evidence; equivalence increasingly difficult to establish; clinical investigation often required |
The clinical evaluation process — Annex XIV Part A
Annex XIV Part A defines the required stages:
Stage 1 — Identify applicable GSPR requiring clinical evidence
Review the GSPR and identify which require clinical data for their demonstration. For most devices, this includes at minimum:
- GSPR §1 (fundamental safety and performance — clinical benefit vs. risk)
- GSPR §3 (performance as claimed under conditions of use)
- GSPR §6 (biological safety, where clinical performance data informs biocompatibility)
Stage 2 — Identify available clinical data
Sources of clinical data include:
- Clinical investigations of the device itself (pre- or post-market)
- Clinical investigations of an equivalent device
- Published peer-reviewed literature on the device or equivalent device
- Post-market clinical follow-up (PMCF) data
- Post-market surveillance data (complaints, vigilance, registry data)
Stage 3 — Appraise the clinical data
Each data source is critically appraised for:
- Relevance to the device under evaluation
- Scientific validity (study design, methodology, bias risks)
- Clinical weight (how much confidence the data supports)
A literature search protocol (with documented search strategy, databases, inclusion/exclusion criteria) is required.
Stage 4 — Generate new clinical data if necessary
If existing data is insufficient to demonstrate safety and performance, new clinical data must be generated — through a clinical investigation (pre-market) or PMCF (post-market).
Stage 5 — Analyse the clinical data
Synthesise all appraised data to reach conclusions on:
- Whether the device achieves its claimed performance
- Whether the benefit-risk is positive and acceptable
- Whether GSPR requiring clinical evidence are met
- Whether residual uncertainties exist and how they will be addressed through PMCF
Stage 6 — Write the Clinical Evaluation Report
Document all of the above in a structured CER. See Clinical Evaluation Report (CER).
The equivalence pathway
If the manufacturer does not have sufficient clinical data from their own device, they may use clinical data from an equivalent device. Equivalence under MDR is strictly defined — all three criteria must be met:
| Criterion | What is required |
|---|---|
| Clinical | Same intended use, same medical indication, same user population, same part of the body |
| Technical | Same design, same materials in contact with the body, same deployment method, similar specifications |
| Biological | Same materials, same duration of contact, same absorption characteristics |
Access to equivalence data: MDR Art. 61(5) requires the manufacturer to have sufficient access to the technical documentation of the equivalent device. For a device from a different manufacturer, this requires a contractual arrangement granting access. This is a significant change from MDD practice, where publicly available literature was often deemed sufficient.
For Class III and implantable Class IIb devices: equivalence to a device from a different manufacturer is only permitted in exceptional, justified circumstances. The expectation is that Class III devices will have their own clinical investigations.
When clinical investigations are required
MDR Art. 61(4) states that for implantable Class III devices and Class III devices, clinical investigations must be performed unless:
- The device has been modified from a device already marketed by the same manufacturer, and
- The modifications have been shown by clinical evaluation data not to significantly affect the safety and performance
In practice, for novel Class III devices with no genuine equivalent, a clinical investigation is expected.
The clinical evaluation and the lifecycle
Clinical evaluation is not completed at CE marking — it continues post-market through PMCF. The CER must be updated:
- Whenever significant new clinical data is available
- At minimum annually for Class IIb and III devices
- When PMCF data identifies new safety or performance findings
- When the device is modified
The current CER and PMCF evaluation report are reviewed by the notified body at each surveillance audit.
Related pages
- Clinical Evaluation Report (CER)
- Equivalence claims
- Clinical investigations
- Using international clinical data
- Post-market data in technical documentation
Official references
| Reference | Description |
|---|---|
| MDR Art. 61 | Clinical evaluation requirements |
| MDR Annex XIV Part A | Clinical evaluation stages |
| MDR Annex XIV Part B | PMCF requirements |
| MDCG 2020-5 | Clinical evaluation guidance |
| MDCG 2020-6 rev.2 | Guidance on CER |
| MDCG 2021-6 | Guidance on sufficient clinical evidence for legacy devices |
| EN ISO 14155:2020 | Good clinical practice for medical device investigations |
The equivalence pathway section
Equivalence Criteria
| Criterion | Requirements |
|---|---|
| Clinical | Same intended use, same medical indication, same user population, same part of the body |
| Technical | Same technology or operational principle, similar design specifications, same materials in patient contact |
| Biological | Same materials or equivalent biological safety profiles, same duration of contact, same route of contact |
The equivalence pathway section should be completed with all three criteria. It should read: 'Criterion — Clinical: Same intended use, same medical indication, same user population, same part of the body. Technical: Same technology or operational principle, similar design specifications, same materials in patient contact. Biological: Same materials or equivalent biological safety profiles, same duration of contact, same route of contact.'
Criterion 1 — Clinical: Same intended use (same medical condition, severity, patient population, body site) and similar clinical outcomes. Criterion 2 — Technical: Same technology or operational principle, similar design specifications, same patient-contact materials (or documented equivalent biological safety profiles), similar software/algorithms, and similar energy delivery parameters for active devices. Criterion 3 — Biological: Same or equivalent biological safety profile of materials, same duration and route of body contact (transient, short-term, long-term/permanent implantable), and same absorption, distribution, and degradation characteristics. For devices from different manufacturers, formal written contractual access to technical documentation must be in place continuously. For Class III and implantable Class IIb devices, equivalence is heavily scrutinised and clinical investigations are often required regardless.