Glossary

Here you will find a list of common terms used in clinical research. For more, please see the full Glossary of Common Terms.

ARM:Any of the treatment groups in a randomized trial. Most randomized trials have two "arms," but some have three "arms," or even more.

Double-blind study: A clinical trial design in which neither the participating individuals nor the study staff knows which participants are receiving the experimental drug and which are receiving a placebo (or another therapy). Double-blind trials are thought to produce objective results, since the expectations of the doctor and the participant about the experimental drug do not affect the outcome

Experimental Product or Device:A drug that is not FDA licensed for use in humans, or as a treatment for a particular condition

Institutional Review Board (IRB):  A committee of physicians, statisticians, researchers, community advocates, and others that ensures that a clinical trial is ethical and that the rights of study participants are protected. All clinical trials in the U.S. must be approved by an IRB before they begin.

Open-Label Trial:A clinical trial in which doctors and participants know which drug or vaccine is being administered

Protocol:A protocol is a detailed plan and description of what will be done in a study. It outlines what and when will be done, how it will be conducted, and why.

Principal Investigator (PI): The doctor who is in charge of the study, especially at a particular location.

Placebo: A placebo is an inactive pill, liquid, or powder that has no treatment value. In clinical trials, experimental treatments are often compared with placebos to assess the treatment's effectiveness.

Randomization: A method based on chance by which study participants are assigned to a treatment group in a trial.