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Clinical Trials

Source: MedlinePlus Health Topics, U.S. National Library of Medicine

Last synced 8/10/2026Status: primary verified

Clinical trials are research studies that test how well new medical approaches work in people. Each study answers scientific questions and tries to find better ways to prevent, screen for, diagnose, or treat a disease. Clinical trials may also compare a new treatment to a treatment that is already available. Every clinical trial has a protocol, or action plan, for conducting the trial. The plan describes what will be done in the study, how it will be conducted, and why each part of the study is necessary. Each study has its own rules about who can take part. Some studies need volunteers with a certain disease. Some need healthy people. Others want just men or just women. An Institutional Review Board (IRB) reviews, monitors, and approves many clinical trials. It is an independent committee of physicians, statisticians, and members of the community. Its role is to: Make sure that the study is ethical Protect the rights and welfare of the participants Make sure that the risks are reasonable when compared to the potential benefits In the United States, a clinical trial must have an IRB if it is studying a drug, biological product, or medical device that the Food and Drug Administration (FDA) regulates, or it is funded or carried out by the federal government. NIH: National Institutes of Health

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This information is for general education and is not medical advice. Always talk to a licensed U.S. clinician about your situation, medications, or treatment decisions.