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Managing Cancer Care

Informed Consent for a Clinical Trial

Informed consent for a clinical trial or study may include an investigational drug or procedure (where new treatments are compared to the current standard treatment). This process usually include more information than the consent forms for standard treatment. The informed consent process for clinical trials is meant to give you ongoing information to help you make an educated decision about whether to start or stay in a clinical trial.

A person who is thinking about being part of a clinical trial is called a potential research subject. If a person decides to be part in a clinical trial, this is referred to as enrolling or enrollment in the study. As a potential research subject, you must be given an opportunity to read the consent document fully, and to ask questions about anything you do not understand. The consent form for a clinical trial or research study should clarify the following information.

  • The purpose of the research
  • How long it is expected to take.
  • A statement saying the study involves research.
  • That research subject participation is voluntary and that refusing treatment will not result in not receiving the care that they need.
  • All the procedures that will be completed during the enrollment into the clinical trial.
  • Any possible benefits and risks that may be expected from the research.
  • Any possible discomfort (e.g., injections, frequency of blood tests etc.)
  • Any alternative procedures or treatment (if any) that might benefit the research subject.
  • How the potential subject's information will be kept private during the clinical trial and that the FDA (Food and Drug Administration) may inspect the records at any time.
  • Whether any compensation (payment) or medical treatments are available if injury occurs and where that information may be found.
  • The research subject's rights; such as the right to refuse treatment or stop participation in the clinical trial at any time, without losing any treatment benefits.
  • Contacts for answers to questions related to the clinical trial and to report any injuries that may occur.

Before signing the form be sure you understand all the information given to you and have had a chance to ask questions about what you don't understand. You can bring a family member or friend that you trust to help you keep track of your information. If you need extra time to review the information, you may ask your health care provider to give you a copy of the informed consent form so you can take it home and review it as many times as you need before making a decision.

If you take part in a clinical trial, during the study it's possible that the research team may make new discoveries that could affect your health, well-being, or willingness to stay in the clinical trial. They will share this with you and might ask you to sign a new consent form. Remember, you can leave the clinical trial if anything happens or any information leads you to have doubts about staying in it.

A contact person and phone number for more information should be given to you at the first meeting where the informed consent forms are presented to you. While your health care team will likely be a helpful source of information, only you can make the decision about being in a study. Not even the best medical experts can predict whether a method being studied in a clinical trial will work for you. The informed consent process is designed to help you weigh all of the pros and cons and make the best choice for yourself

Tips about clinical trials

  • Keep a copy of the consent form. Ask for a copy if one isn’t offered to you. You may also request a copy of the protocol (full study plan) that describes all the details of the clinical trial.
  • According to US regulations, no informed consent document may say anything that asks or seems to ask you to give up (waive) any legal rights. It also may not include anything that appears to not hold the investigator, doctor, sponsor, or facility accountable if they are negligent or careless.
  • If you cannot understand the forms you are asked to sign, don’t be afraid to let someone know that you are having trouble. Many people feel nervous about signing consent forms and talking with health care providers. Take your time and ask for help when you need it.

We have more information that can help you understand clinical trials. Call us at 1-800-227-2345 or visit Clinical Trials online to find information, worksheets, and videos that can help you decide if a clinical trial is right for you.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as editors and translators with extensive experience in medical writing.

Kadam RA. Informed consent process: A step further towards making it meaningful! Perspectives in Clinical Research; 2017; 8(3): 107-112.

National Cancer Institute (NCI). Informed consent. 2016. Accessed at on February 19, 2019.

Office for Human Research Protections. Informed consent FAQs. 2017. Accessed at on February 19, 2019.

U.S. Food & Drug Administration (FDA). Informed consent for clinical trials. 2018. Accessed at, on February 19, 2019.

Last Revised: May 13, 2019

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