What is the “control arm” of a clinical trial?

A clinical trial is a research study conducted with human beings to see if a new medical device, medication or other treatment is effective and safe. Some study participants will be assigned to a “control arm” or “control group” in the study.
Those who are in the control arm will not receive the new medication, device or treatment that is under study, to provide a comparison to see how the innovation compares against no treatment or an old treatment. Members of the control group may receive a placebo, an inactive treatment such as a pill that makes the group think they are receiving the new treatment.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.