This glossary contains a list of words used in clinical trials. It also contains other terms that you may hear from your doctor or nurse.
Bias: Human choices or any other factors beside the treatments being tested that affect a study's results. Clinical trials use many methods to avoid bias, because biased results may not be correct.
Clinical trials: Research studies that involve people. Each study tries to answer scientific questions and to find better ways to prevent or treat cancer.
Control group: In a clinical trial, the group of people that receives standard treatment for their cancer.
Informed consent: The process in which a person learns key facts about a clinical trial or research study and then agrees voluntarily to take part or decides against it. This process includes signing a form that describes the benefits and risks that may occur if the person decides to take part.
Institutional Review Board (IRB): Groups of scientists, doctors, clergy and consumers at each health care facility at which clinical trial takes place. Designed to protect patients who take part in studies, IRBs review and must approve the protocols for all clinical trials funded by the Federal Government. They check to see that the study is well-designed, does not involve undue risks, and includes safeguards for patients.
Investigator: A researcher in a treatment study.
Oncologist: A doctor who specializes in treating cancer.
Placebo: A tablet, capsule, or injection that looks like the drug or other substance being tested but contains no drug.
Protocol: An action plan for a clinical trial. The plan states what will be done in the study and why. It outlines how many people will take part in the study, what types of patients may take part, what tests they will receive and how often, and the treatment plan.
Randomization: A method used to prevent bias in research. People are assigned by chance to either the treatment or control group.
Remission: When the signs and symptoms of cancer go away, the disease is said to be "in remission." A remission can be temporary or permanent.
Side effects: Problems that occur when treatment affects healthy cells. Common side effects of standard cancer treatments are fatigue, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores. New treatments being tested may have these or other unknown side effects.
Single blind study: A method used to prevent bias in treatment studies. In a single blind study, the patient is not told whether he/she is taking the standard treatment or the new treatment being tested. Only the doctors know.
Stage: The extent of a cancer and whether the disease has spread from the original site to other parts of the body. Numbers with or without letters are used to define cancer stages (e.g., Stage IIb).
Standard treatment: The best treatment currently known for a cancer, based on results of past research.
Treatment group: The group that receives the new treatment being tested during a study.
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