Why are DiGA studies, NUB studies, and scientific clinical studies different from "normal" PMCF studies?

DiGA, NUB, and scientific clinical studies pursue different legal and healthcare objectives than "normal" PMCF studies; therefore, they differ significantly in their legal basis, research question, methodology, endpoints, and integration into care pathways.

Let's start with the commonalities: 

All these study types are clinical studies involving medical devices that must be planned and conducted according to common scientific, ethical, and regulatory principles. Most of these medical devices are CE-certified, the study is conducted within the scope of the intended purpose and can be performed with or without invasive or burdensome measures. Likewise, all are planned and conducted according to scientific standards, in line with applicable regulatory and ethical standards; they all generate clinical evidence and are intended to benefit patients and demonstrate the utility of the medical device in diagnostics and therapy.

Regardless of whether it's a DiGA, NUB, PMCF, or "other" study – you need a professional clinical study set-up; the difference lies primarily in the main objective (regulatory vs. reimbursement vs. research) and the endpoints addressed, not in the fundamental principles of good clinical research.

‍

What is meant by a "normal" PMCF?

- These are usually observational studies of lower scientific quality

DiGA Studies: Evidence for Positive Healthcare Effects

• DiGA studies are (as of spring 2025 worldwide) a unique German case: They serve to demonstrate "positive healthcare effects" (medical benefit or patient-relevant structural/procedural improvement) as a prerequisite for inclusion in the BfArM DiGA directory and thus for reimbursement by German statutory health insurance funds.
• Methodologically, the DiGA guideline requires a controlled, quantitative, usually randomized superiority study that demonstrates that the use of the DiGA is better than non-use or standard care.
• DiGA studies are often designed as PMCF studies with an already CE-marked product, but their content is more health-economically and patient-centrically oriented and closely linked to the BfArM assessment procedure.

NUB Studies: Reimbursement and G-BA Logic

• NUB studies (in the DRG context) primarily aim at assessing a "New Examination and Treatment Methods" status and thus at (additional) hospital reimbursement or reimbursement for an outpatient product, not at regulatory PMCF objectives. They are initiated and later evaluated by the Federal Joint Committee (G-BA).
• In practice, NUB studies are planned to reflect healthcare effects, cost-benefit aspects, and impacts on hospital economics, as well as G-BA-relevant endpoints; they are thus closely linked to the GKV benefit assessment. Similar to DiGA studies, they have very high scientific standards, whereby the G-BA's recommendations must be implemented as direct requirements, or scientifically sound alternatives must be argued for.
• Formally, NUB studies can be classified regulatorily as "other clinical investigation" or as biomedical research with medical devices if they are not directly part of the clinical development plan under the MDR.

"Scientific" Clinical Studies: Research Instead of Product Surveillance

• Scientific clinical studies involving CE-marked products that do not pursue conformity assessment or systematic PMCF are considered "other clinical investigations" in the EU, and specifically in Germany. Their primary purpose is to answer scientific or care-related questions outside the MDR development plan.
• Examples include health services research or endpoint studies conducted within the intended purpose without additional burdensome measures. These are primarily regulated by ethics committees and professional law, rather than by Articles 62–80 MDR.
• Endpoints can include, for example, quality of life, adherence, process and structural indicators, or health economic parameters, without necessarily prioritizing regulatory PMCF requirements.

‍

Drawing on our many years of experience, we are happy to advise you on the focus of your study (e.g., regulatory affairs, reimbursement, health services research), tailored to your primary objective. Based on this, we select the appropriate study type and legal framework for your project (DiGA study, PMCF, NUB, other scientific study, or other) and then define the study design, endpoints, and submission pathway.

Is this of interest to you? Contact us for an initial consultation!

‍