Deciding to be in a clinical trial

Choosing to participate in a clinical trial is a personal decision, and your reasons for signing up may be different from someone else’s. It may help you feel more actively involved in the decisions about your treatment. You may join a trial because your treatments didn’t work or there are no other treatment options for your type or stage of cancer. Maybe you want the chance to have a new and promising treatment, such as targeted therapies. Or you may want to contribute to developing new ways to treat cancer, like personalized medicine.

Some people choose to be in a clinical trial because they want to contribute to the science that helps us understand cancer better. When you are in a clinical trial, you are part of the research that could bring new hope to others, maybe even your own family and loved ones.

Learn all that you can about the trial

Before deciding to take part, it’s important to learn all that you can about the trial. Talk to your healthcare team and to the clinical trials team. Ask lots of questions so you can make the best choice for you. Make sure that you understand the:

  • type of trial
  • risks and benefits
  • costs and time involved

To make the decisions that are right for you, ask your healthcare team questions about clinical trials.

How you’re protected

To protect your health, safety and privacy, every trial must follow strict rules and meet high standards.

Your safety is always being considered and monitored when you are part of a clinical trial. The trial may be stopped if:

  • The early results of the trial show that the treatment being tested does not work as expected.
  • Serious side effects occur during the clinical trial.
  • Early results show that the new treatment being tested works better than standard treatment (the treatment that is accepted and commonly used to treat that type and stage of cancer). In this case, all the people in the clinical trial are offered the new treatment.

Leaving a clinical trial

Taking part in a clinical trial is voluntary. You may leave the trial (this is called withdrawing your consent) at any time. This doesn’t mean that you won’t be treated any more. You will still be given the best standard treatment after leaving a clinical trial.

The clinical trial team may also take you out of the trial if they have concerns about your safety and well-being.

If you do decide to leave a clinical trial, let the clinical team know that you are leaving and why.

Expert review and references

  • American Cancer Society. The basics of clinical trials. 2016.
  • American Cancer Society. Making the decision about clinical trials. 2016.
  • Delacruz A & McCall S . Principles of cancer clinical trials. Yarbro CH, Wujcki D, Holmes Gobel B, (eds.). Cancer Nursing: Principles and Practice. 8th ed. Burlington, MA: Jones and Bartlett Learning; 2018: 9: 227-242.
  • National Cancer Institute. What are clinical trials?. 2016: https://www.cancer.gov/about-cancer/treatment/clinical-trials/what-are-trials.
  • National Cancer Institute. Deciding to take part in a clinical trial. 2016.
  • National Institutes of Health. Are clinical studies for you?. 2017.

Medical disclaimer

The information that the Canadian Cancer Society provides does not replace your relationship with your doctor. The information is for your general use, so be sure to talk to a qualified healthcare professional before making medical decisions or if you have questions about your health.

We do our best to make sure that the information we provide is accurate and reliable but cannot guarantee that it is error-free or complete.

The Canadian Cancer Society is not responsible for the quality of the information or services provided by other organizations and mentioned on cancer.ca, nor do we endorse any service, product, treatment or therapy.


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