Reading MDCG 2020-5: The Clinical Evaluation Guidance That Auditors Use

MDCG 2020-5 is the primary EU-level guidance document on clinical evaluation for medical devices under MDR — and if you're preparing a CER for Notified Body review, this is the document your auditors are trained against. Published by the Medical Device Coordination Group in April 2020 and covering Article 61 and Annex XIV of EU MDR (and equivalent IVDR provisions), it sets out the methodological framework that Notified Bodies use to assess whether your clinical evaluation holds up. Understanding what it says — and what it doesn't say — is one of the more practical things you can do before submitting.

What MDCG 2020-5 is and who it applies to

The document is guidance, not law — but the practical distinction is smaller than it sounds. Notified Bodies in the EU are expected to follow MDCG guidance in their assessments, and when a CER diverges from MDCG 2020-5 without explicit justification, it is treated as a red flag. If you choose a different approach from what MDCG 2020-5 describes, you need to document your rationale clearly.

It applies to all device categories covered by MDR, though some sections address specific risk classes separately.

The Clinical Evaluation Plan — the part teams skip

One of the most important things MDCG 2020-5 establishes is the requirement for a documented Clinical Evaluation Plan (CEP) before the CER is produced. The guidance is explicit that the CEP must define the scope, objectives, methodology, and acceptance criteria in advance of the evaluation. The CER then documents the execution of that plan.

In practice, many teams write the CER first and produce the CEP to match. MDCG 2020-5 describes the order as the other way around, and Notified Bodies are increasingly checking for version dates to see which came first. Getting the CEP written and approved before the literature search begins is not just procedural — it's the evidence that your evaluation was prospectively planned and not retrospectively rationalised.

The literature search methodology requirements

Section 4 of MDCG 2020-5 covers literature search in detail. The guidance requires:

• A defined, documented search strategy with explicit search terms
• Specification of which databases were searched
• Documented inclusion and exclusion criteria applied consistently
• A PRISMA-style flow diagram or equivalent showing how the final set of included papers was reached from the initial search results

The rationale behind this level of documentation is reproducibility. Your search methodology should be detailed enough that another person could replicate it and get the same results. Teams that produce CERs with a paragraph summarising their literature review without methodology documentation consistently struggle at Notified Body review.

Literature appraisal — the step most teams underdo

Finding literature is one thing. Appraising it is what MDCG 2020-5 spends considerable time on. The guidance requires critical appraisal of each included study — assessment of study design, risk of bias, relevance of the patient population, appropriateness of endpoints, and applicability to your specific device and intended purpose.

In practice, this means each included study should have an individual appraisal entry, not just a citation. Teams that produce CERs with a bibliography and a single paragraph saying "the literature supports device safety" fail this requirement. What Notified Bodies want to see is evidence that you read the papers critically, understood their limitations, and drew conclusions that are proportionate to the evidence quality.

How MDCG 2020-5 handles equivalent devices

Section 3 of MDCG 2020-5 addresses the use of data from equivalent devices, cross-referencing MDCG 2020-6 (the dedicated equivalence guidance). The key points from 2020-5 for practitioners:

• Equivalence must be demonstrated, not asserted
• The demonstration must be documented in the CER
• If access to another manufacturer's technical documentation is required, that access must be contractually established — and you must be able to show this to the Notified Body

MDCG 2020-5 is also clear that using data from a device class or technology category (e.g., "all balloon catheters") as a proxy for equivalence does not meet the MDR requirement. Equivalence is device-specific.

The benefit-risk analysis requirements

MDCG 2020-5 requires the CER to include a structured benefit-risk analysis based on the clinical data appraised. This is not the same as your ISO 14971 risk management summary — it is specifically a clinical benefit-risk assessment that draws on clinical evidence.

The guidance describes the analysis as needing to weigh clinical benefits against the probability, severity, and duration of adverse events — based on the actual evidence reviewed, not generic device class data. A benefit-risk analysis that references only the risk management file without engaging with clinical evidence will not satisfy this requirement.

Using MDCG 2020-5 as an audit preparation tool

The most practical way to use this document is to treat it as a checklist before you submit your CER for Notified Body review. Work through each section of the guidance and confirm your CER addresses the corresponding requirement. Where you've taken a different approach, document your rationale.

The MDCG guidance library is publicly available, and the document is not long — about 50 pages including annexes. The effort to read it carefully before finalising your CER is significantly smaller than the effort to address a Notified Body's major findings after the fact.