Definition of clinical trials vs. clinical studies

The regulations and procedures for registering and reporting results for clinical trials differ than those for clinical studies. Understanding these differences are essential in respect to legal and regulatory requirements.

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Registration and reporting procedures for both “clinical trials” and “clinical studies” have distinctive requirements. It is important to note that not all clinical studies qualify as a clinical trial under the EU Directive/EU Regulation. The European Union (EU) Directive 2001/20/EC defines a clinical trial as follows:

Clinical Trial

Any investigation in human subjects intended to discover or verify the clinical, pharmacological and/or other pharmacodynamic effects of one or more investigational medicinal product(s), and/or to identify any adverse reactions to one or more investigational medicinal product(s) and/or to study absorption, distribution, metabolism and excretion of one or more investigational medicinal product(s) with the object of ascertaining the safety and/or efficacy of those medicinal products.”

Clinical studies, on the other hand, are more generalizable and can include both interventional and non-interventional studies; however, clinical studies DO NOT involve investigational medicinal products (IMPs), as opposed to clinical trials. 

Clinical Study

“Any research study that prospectively assigns human participants or groups of humans to one or more health-related interventions to evaluate the effects on health outcomes, which include, but are not restricted to drugs, cells and other biological products, surgical procedures, radiological procedures, devices, behavioral treatments, process-of-care changes, preventive care, etc.”

The regulations for registering and reporting a clinical trial differ than those for a clinical study, therefore, distinguishing the differences between these two terms are very important. For the purpose to differentiate between the terminology, Karolinska Institutet (KI) describes the term “clinical trial” (klinisk läkemedelsprövning) as a “trial that is subject to approval by the Swedish Medical Products Agency (MPA)”, as opposed to the term “clinical study” (klinisk studie), which refers to other “interventional studies” and “non-interventional studies” that do NOT require MPA approval. Information regarding the different regulations for clinical trials and clinical studies can be found on the “Regulations and Requirements” webpage.

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