Injury
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Clinical relevance and statistical significance are different concepts, linked via the sample size calculation. Threshold values for detecting a minimal important change over time are frequently (mis)interpreted as a threshold for the clinical relevance of a difference between groups. The magnitude of a difference between groups that is considered clinically relevant directly impacts the sample size calculation, and thereby the statistical significance in clinical study outcomes. ⋯ The magnitude of a clinically relevant difference between groups should be carefully considered, by determining the smallest effect for each specific study that is considered worthwhile. This means taking into account the (dis)advantages of both study interventions in terms of benefits, harms, costs, and potential side effects. This article clarifies common sources of confusion, illustrates the implications for clinical research with an example and provides specific suggestions to improve the design and interpretation of clinical research.
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In May 2021, the new Medical Device Regulation in the EU came into force. While the US has a centralized governmental authority, the Food and Drug Administration (FDA), the EU implemented a system of different Notified Bodies responsible for the approval process of medical devices. Both regions have a similar system to classify medical devices based on their overall risks but specific devices, like joint prostheses, are classified differently in the US and the EU. ⋯ In both regions, it is possible to place a new device on the market based on the demonstration of equivalence to an already marketed device, but the MDR significantly increased the regulatory requirements for the equivalence pathway. While an approved medical device in the US in most cases only requires general post-market surveillance activities, manufacturers in the EU must continuously collect clinical data and submit specific reports to the Notified Bodies. In this article, we will compare the regulatory requirements between the US and Europe and provide an overview of similarities and differences.