The Clinical Trials Act introduced in Japan in April 2018 requires measures to ensure the safety of subjects. As defined in the act, the term “clinical trials” refers to such research that is conducted to clarify an efficacy or safety of medicines, medical devices, and medical instrument by testing them in people, that is, by using them in a medical practice. If a research is recognized as a clinical trial, the act requests judicious procedure to conduct the research. However, the definition of medical practice has not been interpreted systematically. Therefore, medical-engineering researchers have difficulty in deciding whether their study involves a medical practice. As a result, the act may cause reduction of researches in biomedical engineering. Here, we try to clarify the principles used to decide whether a research is classified as a “clinical trial” and to provide a summary for medical-engineering researchers as a guideline of the Japanese Society for Medical and Biomedical Engineering. We apply the guideline to several examples to show its efficiency.
