At medXteam, the focus is on clinical data. In this context, as CRO we not only carry out clinical trials with medical devices in accordance with MDR and ISO 14155, but also offer all other options and forms of data collection. No matter which form of data collection you choose: The foundation is solid planning but also dealing with the various options and the respective requirements. A good example of the fact that with the MDR requirements are not only becoming more stringent and increasing is what is presented in this blog post: namely the changed qualification requirements for study staff and the consequences that result from this, which in certain cases even lead to one lead to relief.


MDR Medical Device Regulation; EU Regulation 2017/745

MPDG Medical Devices Implementation Act

MPAnpG Medical Devices Adaptation Act

MPG Medical Devices Act

LKP Head of Clinical Trials

Underlying regulations

EU Regulation 2017/745 (MDR)
Medical Devices Implementation Act (MPDG)

1 Introduction

The rapid development in the medical technology industry entails constant adaptation and further development of the legal framework. In particular, the introduction of EU Regulation 2017/745, better known as the Medical Device Regulation (MDR), and the national legislation derived from it in Germany through the Medical Device Adaptation Act (MPAnpG) and the Medical Device Implementation Act (MPDG) have profound effects on planning and Conducting clinical trials.

The consideration of whether to opt for a monocentric or a multicentric design for clinical trials in accordance with Articles 62, 74 or 82 of the MDR plays a central role. Although the MDR and the MPDG entail stricter regulation in many areas, there are also significant simplifications in certain aspects. Such facilitation particularly affects the design of clinical trials. For example, the approval hurdles are significantly lower for monocentric studies. But what exactly are the advantages they offer, and what challenges and requirements do they pose, particularly in terms of the qualifications of the required study staff?

This blog post sheds light on the critical differences and associated regulatory and organizational considerations in the context of clinical trial design. Particular attention will also be paid to the role and requirements of study staff, which are clearly defined and brought into focus by the new legislation.

2. Single-center study vs. multicenter study

The design of a clinical trial depends on various factors, including the type of medical device, the objective of the study and the available resources. Depending on which design is chosen, there are different requirements for the study staff and the organization of the study.

The choice of clinical trial design, whether monocenter or multicenter, has profound implications for implementation, budget, scheduling, and data quality. 

2.1 Monocentric study

A single-center study is a clinical trial conducted at a single center or location. The study team usually consists of an investigator. However, for larger studies at one location or when different departments are involved, the team can also consist of several investigators. In this case, one of the investigators will be appointed as the principal investigator, who will be responsible for the overall coordination of the study. In addition, other participants such as study nurses, who are responsible for patient care and data collection, may be part of the study team.

Advantages of single-center studies:

  • Simplicity: Since only one location is involved, the processes are typically less complex.
  • Cost: Because fewer staff and resources are required, costs are typically lower.
  • Control: The investigator or principal investigator has direct oversight and control over all aspects of the study.
  • Faster communication: With a smaller team and only one location, agreements and decision-making processes are usually faster and more direct.

However, this simplicity and cost savings may be offset by the limited patient pool and geographic limitation. There is a risk that the results will not be universal or that it will be difficult to recruit enough patients for the study. If many patients are required according to statistical sample size planning, this form of design cannot be chosen as it cannot then be implemented in a reasonable time frame.

2.2 Multicenter study

Multicenter studies are clinical trials that are conducted at multiple locations or centers. In such studies, the study team in each center typically consists of an investigator, a study nurse and, if necessary, other professionals involved. Despite the multiple center structure, the process in each center remains similar to that of monocentric studies. The difference is that such a study design requires a principal investigator site. This main investigation center provides the head of the clinical trial (LKP), who coordinates the entire study across all centers.

Advantages of multicenter studies:

  • Patient pool: The participation of several centers enables access to a larger and heterogeneous patient population.
  • Data base: The design allows for broader and more representative data collection as it comes from different populations and locations. The scientific validity also increases due to the involvement of several examiners and the external validity increases.
  • Comparability: Direct comparisons and consistency checks can be carried out through different locations.

However, these advantages may be offset by increased costs, greater organizational effort and coordination requirements between centers.

  • Core factors: costs, effort and study staff:
  • Cost: Multicenter studies can be more expensive than single-center studies due to their size and complexity.
  • Effort: The organizational effort for multicenter studies is significantly higher, especially with regard to the coordination of patient recruitment, data management and communication between the centers.

Study staff: This is one of the most critical aspects. The challenge is to ensure consistent protocols and practices across all centers. This particular sticking point and the associated considerations and strategies are discussed in detail below.

3. Development of qualification requirements for examiners: From MPG to MPAnpG

As the regulatory landscape for medical devices in Germany has evolved, the qualification requirements for people involved in conducting clinical trials have also changed.

3.1 Under the Medical Devices Act (MPG)

According to Section 20 of the Medical Devices Act (MPG), clinical trials had to meet certain requirements. A crucial aspect was that they had to be carried out in an appropriate facility and led by an "appropriately qualified examiner". The MPG gave clear requirements for the qualifications of this examiner: In addition to medical or dental training, he had to be able to demonstrate at least two years of experience in the clinical testing of medical devices.

This requirement applied to all auditors, regardless of whether they were auditors, main auditors or LKP.

3.2 Transition to the Medical Devices Adaptation Act (MPAnpG or MDPG)

With the introduction of the Medical Devices Adaptation Act, the requirements for the qualifications of study staff were specified and expanded.

Since there was no role definition in the MPG and this had to be taken from ISO 14155 before the MPDG came into force, the MPDG now defines at least the roles of main auditor and LKP in § 3 (5,6):

"According to Section 30 of the MDPG, there are clear distinctions between the investigator, the main investigator and the head of a clinical trial. While the principal investigator and investigator continue to play important roles in the clinical trial, the specific qualification of at least two years of experience in the clinical trial of medical devices is now explicitly assigned to the head of a clinical trial or other clinical trial. "

This means that, compared to the previous MPG, the qualification requirements have become more specific and are more specifically tailored to the different roles in the clinical trial process. This shows an increased awareness of the need for clearly defined and strict qualification criteria to ensure the quality and integrity of clinical trials. It also reflects the growing complexity and importance of clinical trials in the process of medical device development and approval.

3.3 Consequences and effects

The ongoing adaptation and refinement of the legal framework has a significant impact on how clinical trials of medical devices are carried out. In particular, the Medical Devices Implementation Act (MPDG) has brought about some fundamental changes that influence the organization and approval of clinical trials.

One such significant change made in the MPDG thus concerns the roles and qualifications of those involved in clinical trials. According to Section 30 of the MDPG, a distinction is now made between the investigator, the main investigator and the head of a clinical trial. It is crucial to recognize that the minimum two years of experience in the clinical testing of medical devices for any investigator, previously required in the MPG, is now only explicitly assigned to the head of a clinical trial or other clinical trial, even in a single-center study. This requirement therefore only applies to multicenter studies.

While auditors and principal auditors continue to play important roles in the process, the specific qualification requirement now applies only to the audit manager.

For single-center studies, this means that the approval process for a clinical trial is significantly simplified. By focusing the two-year experience requirement on the head of a clinical trial and not on each investigator involved, the hurdle for conducting such studies is significantly reduced, as the ethics committee no longer expects this requirement for the investigator and therefore no longer examines it.

4. Conclusion

The conclusion from these observations is evident: the choice between monocenter and multicenter design has a significant impact on the approval, costs, organizational effort and requirements for study staff of a clinical trial. Correct planning and consideration of all relevant aspects are therefore essential for the success of the project. It is crucial to think intensively about the requirements and select the appropriate personnel for the respective type of study.  

The choice between monocenter and multicenter design has significant implications for the approval, cost, effort, and study staff requirements of a clinical trial. Correct planning and consideration of all relevant aspects are therefore essential for the success of the project. It is crucial to think intensively about the requirements and select the appropriate personnel for the respective type of study.

This aspect in particular has a significant influence on the conduct of clinical trials. The Medical Devices Implementation Act (MPDG) has introduced significant changes, particularly with regard to the roles and qualifications of those involved in a clinical trial.

Section 30 of the MDPG and the associated clear distinction between the investigator, the main investigator and the head of a clinical trial have significantly simplified the approval process for monocentric studies. The specification that at least two years of experience in the clinical testing of medical devices is now explicitly attributed to the head of a clinical trial opens up new possibilities in the design of clinical trials and lowers the hurdles to their implementation.

A deeper understanding of the legal requirements and careful selection of the appropriate personnel for the specific type of study are essential key aspects. It is of central importance to deal intensively with these requirements and to plan accordingly.

However, this only applies to clinical trials carried out within the framework of the MDR (Articles 62, 74 and 82). All other clinical trials (e.g. PMCF studies within the intended purpose of the medical device and without stressful examinations remain unaffected. This means that there are no requirements of this type for the LKP in multicenter studies.

5. What we can do for you

If a clinical trial is to be carried out, basic safety and performance requirements must first be met and essential technical documentation must therefore be created.

In addition, all medical device manufacturers require a QMS, including when developing Class I products.

The clinical trial leads to the clinical evaluation, which in turn forms the basis for PMCF activities (including a PMCF study).

We therefore support you throughout your entire project with your medical device with primary reference to the clinical data on the product: from start to finish.

6. How we can help you

At medXteam we clarify whether and if so which clinical trial needs to be carried out under what conditions and according to what requirements during the pre-study phase: In 3 steps we determine the correct and cost-effective strategy in relation to the clinical trial required in your case Data collection.

We also provide support in the areas of development strategy, technical documentation and quality management.

Do you already have some initial questions?

You can get a free initial consultation here: free initial consultation 

medXteam GmbH

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