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Should I Take Part in a Clinical Trial?
    Posted: 08/30/2001    Reviewed: 04/08/2008
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What Is a Clinical Trial?

How Do I Take Part in a Clinical Trial?

How Is a Clinical Trial Planned and Carried Out?

Participating in a Trial: Questions to Ask

Only you can make the decision about whether or not to participate in a clinical trial. Before you make your decision, you might do the following.

  • Learn as much as possible about your disease. See the Cancer Topics section of this Web site for a wide range of information about different types of cancer.
  • Search the National Cancer Institute's (NCI) registry of cancer clinical trials. For guidance, go to Help Using the Basic Clinical Trial Search Form.
  • Contact one of NCI's cancer information specialists. They can answer many of your questions about cancer and clinical trials, and guide you to further information.
  • Talk about this information and how you feel about it with your health care team, family members, and friends to determine what is right for you.

What are the potential risks and benefits of clinical trials?

Potential benefits include

  • health care provided by leading physicians in the field of cancer research
  • access to new drugs and interventions before they are widely available
  • close monitoring of your health care and any side effects
  • a more active role in your own health care
  • if the approach being studied is found to be helpful, you may be among the first to benefit
  • an opportunity to make a valuable contribution to cancer research

Potential risks include

  • new drugs and procedures may have side effects or risks unknown to the doctors
  • new drugs and procedures may be ineffective, or less effective, than current approaches
  • even if a new approach has benefits, it may not work for you

How are participants protected?

The government has a system designed to protect human research subjects. Before a government-funded clinical trial can begin, the trial plan (also called a protocol) must be approved. During the trial, review committees make sure that the plan is being followed and participants are being protected. See Protecting Participants in Clinical Trials for more information.

Regulations require the researchers performing studies to thoroughly inform patients about a study's treatments and tests and their possible benefits and risks before a patient decides whether or not to participate in any study. This process is called informed consent.

What is informed consent?

Informed consent is a process in which you learn the key facts about a clinical trial before you decide whether or not to participate. In addition to talking about these facts with the research doctor or nurse, they will be included in a written consent form that you can take home to read and discuss. The consent form will include details about

  • the study approach
  • the intervention given in the trial
  • the possible risks and benefits
  • the tests you may have

Don't hesitate to ask questions until you have all the information you need (see Participating in a Trial: Questions to Ask Your Doctor). While informed consent begins before you agree to participate in a trial, you should feel free to ask the health-care team any questions you have at any point. Informed consent continues as long as you are in the study. You can change your mind and leave the study whenever you want -- before the study starts or at any time during the study or follow-up period.

Could I receive a placebo?

A placebo is an inactive substance or treatment that looks the same as, and is given the same way as, an active drug or treatment being tested in a clinical trial. In treatment trials involving people who have cancer, placebos are very rarely used.

Many treatment trials are designed to compare a new treatment with a standard treatment, which is the best treatment currently known for a cancer based on results of past research. In these studies, patients are randomly assigned to one group or another. When no standard treatment exists for a cancer, a study may compare a new treatment with a placebo. However, you will be told about this possibility during informed consent, before you decide whether or not to take part in the study.

What happens during a trial?

If you decide to participate in a clinical trial, you will work with a research team. Team members may include doctors, nurses, social workers, dieticians, and other health care professionals. They will provide your care, monitor your health carefully, and give you specific instructions about the study.

Participating in a trial may mean that you might have more tests and doctor visits than you would if you weren't in the study. Team members also may continue to stay in contact with you after the trial ends. To make the trial results as reliable as possible, it is important for participants to follow the research team's instructions. That means having all doctor visits and tests, taking medicines on time, and completing logs or answering questionnaires.

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