PMS, PMCF and Trending: Requirements and practical experiences under the MDR
The MDR places high demands on a structured and proactive post-market surveillance system. In particular, the interplay between PMS, PMCF and trending raises many questions in practice. This article highlights the differences between product-related market surveillance and patient-related clinical data, discusses typical expectations of Notified Bodies – particularly regarding clinical evaluation via equivalence – and outlines the current requirements set out in Guidance MDCG 2025-10.
Introduction: PMS as the basis for post-market activities
The MDR has significantly strengthened Post-Market Surveillance (PMS) and established it as a continuous process throughout the entire life cycle of a medical device.
The PMS system is an integral part of the quality management system and is based on a PMS plan drawn up during product development. Among other things, this plan defines data sources, data collection methods and criteria for evaluating the results. Typical sources include, for example, complaints, literature reviews, registry data, user feedback and trend analyses.
Within this system, Post-Market Clinical Follow-up (PMCF) plays a special role. PMCF is part of the PMS system but has a specific focus: the targeted collection of clinical data from the real-world use of the product in order to confirm clinical safety and performance in the long term or to identify new risks.
PMS and PMCF – Differences and Interaction
Although PMS and PMCF are closely linked, they take different perspectives. PMS is fundamentally product-oriented, whilst PMCF is more patient- or usage-oriented.
The PMS system considers the product as a whole within the market environment. Data is collected that provides insight into the general safety, performance and reliability of a product. This includes, for example, complaints, service reports, literature data or information on comparable products on the market. The aim is to identify trends, reassess risks and, where necessary, initiate measures such as design changes or corrective actions.
PMCF, on the other hand, focuses more strongly on clinical use in patients. The primary question here is how a product affects patients in actual use and whether its clinical performance meets expectations. Accordingly, data is frequently obtained through clinical trials, registries, structured user surveys or other forms of systematic clinical data collection. The MDR therefore describes PMCF as a continuous process for updating the clinical evaluation based on real-world clinical experience.
Both approaches complement each other. Whilst PMS provides a broad picture of a product’s performance in the market, PMCF enables an in-depth clinical examination of actual use and its effects on patients.
PMCF in practice – experiences by risk class, product type and technology
In practice, it is evident that the scope and nature of PMCF activities depend heavily on risk class, degree of innovation and product type. For higher-risk or particularly innovative products, a more extensive PMCF is often expected, as there is greater uncertainty regarding long-term clinical performance.
For Well-Established Technologies (WET) the scope of PMCF activities may generally be smaller, provided there is sufficient clinical evidence. Nevertheless, WET does not automatically mean that PMCF can be dispensed with. Rather, the manufacturer must assess whether existing data is suitable for confirming the product’s clinical safety and performance in the long term.
In this context, particular attention is paid to clinical evaluation via the equivalence route. If the clinical evidence is derived predominantly from data on an equivalent product, Notified Bodies often place greater emphasis in practice on the design of the PMCF measures. The reason for this is that in such cases, there is limited or no direct clinical data available on the manufacturer’s own product.
Accordingly, the post-market phase is expected to address this gap. PMCF activities should specifically contribute to confirming that the safety and clinical performance of the manufacturer’s own product in real-world use are consistent with the assumptions made in the equivalence assessment.
In practice, this means that a clearly structured and well-justified PMCF plan (in accordance with MDCG 2020-7) is required. This should define suitable data collection methods and endpoints, for example via registry data, structured user or patient surveys, literature reviews or – if necessary – specific PMCF studies. Equally important is a transparent strategy for evaluating the collected data, as well as defined thresholds or criteria which, if exceeded, will necessitate further action.
Trends, guidance and current developments (including MDCG 2025-10)
Another key component of the PMS system is trend analysis (trending). Manufacturers must analyse whether the frequency or severity of incidents is increasing in a statistically significant manner. Such trends may indicate new risks or problems in product design and must be assessed accordingly and reported where necessary.
The regulatory requirements for trending stem primarily from Article 88 of the MDR, which provides for trend reporting in the event of significant changes. However, there are only limited specific methodological guidelines. Manufacturers must therefore define suitable statistical methods and thresholds themselves, which are described in the PMS plan.
The current guidance “MDCG 2025-10 Guidance on post-market surveillance of medical devices and in vitro diagnostic medical devices” also emphasises the central role of a structured PMS system. It describes how manufacturers should identify suitable data sources, systematically collect and analyse data, and derive conclusions and actions from this. Particular emphasis is placed on the proactive nature of PMS. Manufacturers should not merely react to incoming complaints or vigilance reports, but should proactively seek out relevant information and integrate it into their PMS system in a structured manner.
In this context, “proactive” means that the PMS plan already specifies which data sources are to be regularly evaluated and the methods to be used to collect and analyse this information. This includes, for example, systematic literature reviews, the analysis of publicly available information on comparable products, the evaluation of registers or databases, and structured feedback from users, patients or distribution partners. Specifically generated data – for example, as part of PMCF activities – can also form part of this proactive approach.
The aim of this approach is to identify potential risks, trends or changes in clinical use as early as possible, before they manifest themselves, for example, in an increased number of complaints or serious incidents. At the same time, a proactive PMS system makes it possible to take into account developments in the state of the art or changes in clinical practice, and to continuously assess the performance of one’s own product within the market environment. In this way, PMS becomes not merely a reactive safety tool, but a strategic instrument for the continuous improvement of a product’s safety, performance and risk-benefit profile.
Despite the existing guidance, regulatory practice shows that some aspects – particularly in the area of trending or the specific design of PMCF activities – still leave relatively wide scope for interpretation.
Manufacturers are therefore often required to pragmatically reconcile regulatory requirements, existing guidance and the expectations of Notified Bodies. We would be happy to support you in this.
