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Deciding Whether to Be Part of a Clinical Trial

Each clinical trial has benefits and risks. Before you decide to be in one, you need to have all your questions answered. Some people take notes, record meetings with the clinical team, or bring a friend with them to help remember the answers and think of other questions.

Questions to ask before joining a clinical trial

  • What phase is this clinical trial in?
  • Why is this study being done?
  • How long do I have to make this decision?
  • What’s likely to happen if I decide to take part or not take part in the clinical trial?
  • Will the researchers work with my cancer doctor? Who will be in charge of my care?
  • Who will I get in touch with if I have problems, questions, or concerns?
  • What are my other options (standard treatments, other clinical trials)? What are the pros and cons of each?
  • How much do you know about this treatment? About clinical trials in general?
  • What were the results in past studies of this treatment? How likely are they to apply to me?
  • Is there anything else I can read about this clinical trial?
  • What kinds of treatments and tests would I need to have? How often are they done?
  • Would I need to plan on extra time or travel?
  • What side effects might I expect from the trial treatment? Are there other risks? How do these side effects compare to the side effects from standard care for my illness?
  • How will we know if the treatment is working?
  • Will I have to be in the hospital for any part of the trial? If so, how often, for how long, and who will pay for it?
  • Will I still be seeing my regular cancer doctor?
  • Will I have to pay for anything? Will my insurance cover the treatment?
  • If I am harmed as a result of the research, what treatment will I be entitled to?
  • How long will I be in the clinical trial? How long will the clinical trial last?
  • Will I still be able to work if I am in the clinical trial?
  • Are there reasons I could be removed from the clinical trial? Are there reasons the clinical trial might be stopped early?
  • Is long-term follow-up care part of the trial? What would it involve?
  • If the treatment is working for me, can I keep getting it even after the clinical trial ends?
  • Can I talk to other people taking part in the clinical trial?
  • Will I be able to find out about the results of the clinical trial?
  • Is there anything else I can read about this clinical trial?

You might find it helpful to include trusted friends and family members in your decision-making process. They might ask questions you hadn’t thought of and can help you make sure that you’re choosing what's right for you. Also, getting a second opinion from a doctor who’s not part of the study may help you decide if a certain study is the best option for you.

Risks versus benefits

Each clinical trial has its own benefits and risks. But for the most part, clinical trials (other than phase 0) have some of the same potential benefits:

  • You might help others who have the same disease by helping to advance cancer research.
  • You could get a treatment that’s not available outside of the trial. This treatment might be safer or work better than current options.
  • This may increase the number of your treatment options.
  • You may feel more control by taking a more active role in your health care.
  • You’ll likely see your cancer care team more often so that they can monitor your disease and check for side effects of the new treatment.
  • Some study sponsors may pay for part or all your medical care and other expenses during the trial. (This isn’t true for all clinical trials.)

Some possible risks of being in a clinical trial can include:

  • The new treatment may have unknown side effects or other risks which might be worse than those from standard treatments.
  • The new treatment may not work for you even if it helps others.
  •  You may need to have more doctor visits or testing which may require more time and travel.
  • If you take part in a randomized clinical trial , you may not have a choice about which treatment you get. If the study is blinded, you (and maybe your doctor) won’t know which treatment you’re getting. (This information will be available to the clinical trial team as needed for your safety).
  • Insurers may not cover all costs of the clinical trial. They usually do cover the costs of what would normally be standard care. Be sure to talk to your insurance provider and someone involved with the clinical trial before you decide to take part.

Common concerns about clinical trials

Most people have some concerns about taking part in a clinical trial because they’re not really sure what it will mean for them. Get as much information as you need to make the choice that’s right for you.

Will there be risks?

Yes, all clinical trials have risks. But any medical test, treatment, or procedure has risks. The risk may be higher in a clinical trial because there are more unknowns. This is especially true of phase I and II clinical trials, where the treatment has been studied in fewer people.

Perhaps a bigger question is if the possible benefits outweigh the risks. People with cancer are often willing to accept a certain amount of risk for a chance to be helped. But it’s always important to be clear on what this chance is. Ask your doctor to give you an idea of what the benefits may be and which is likely for you. Some people may decide that any chance of being helped is worth the risk, while others may not. Others may be willing to take certain risks to help others.

Will I be a “guinea pig?”

You will not be a guinea pig, but it's true that the purpose of a clinical trial is to answer a medical question. People who take part in clinical trials may need to do extra things or have certain tests done as part of the clinical trial.

But this doesn’t mean that you won’t get excellent care while in the study. In fact, most people enrolled in clinical trials welcome the extra attention they get from their cancer care team.

Studies have shown that people with cancer who felt well informed before they took part in a clinical trial had less regret after the study than those who felt unsure. That’s why it’s important to take your time, ask questions, and feel good about your decision.

Will I get a placebo?

A placebo is a fake pill or treatment used in some types of clinical trials to help make sure results are from the new treatment or drug. A placebo pill is sometimes called a “sugar pill.” Placebos are rarely used alone in clinical trials unless there is no known effective treatment. Most cancer clinical trials do not use placebos unless they are given along with an active drug. It’s unethical to give someone a placebo instead of a treatment that’s known to work.

There are some types of cancer that no treatments have proven to help. In rare cases, testing a new treatment against a placebo might be needed to prove that the treatment is better than nothing at all. The very least you should expect from any clinical trial is to be offered the treatment standard of care.

Can my doctor or I pick which group I’m in?

Not for studies that are randomized. This means that each person in the study gets assigned by chance to either the treatment group or the control group (who get the best current treatment). Randomization helps decrease the chance that the people in one group will be so different from the other that it could affect outcomes. Randomization helps to make sure that the groups have people in similar states of health, so the results are not affected by differences between the groups. If people could choose which treatment they got, the study results might not be as accurate.

Some people find the concept of randomized clinical trials distressing, since neither the patient nor the doctor can choose which group the patient is in. This can be especially true if a trial is looking at totally different treatments and a person believes that one is better than the other. But remember, doctors are doing the study because they really don’t know which one is better. And sometimes taking part in such a study is the only way a person has a chance of getting a new treatment.

Will I know which group I’m in? Will my doctor know?

Each study is different. In a blinded study, the patient doesn’t know which treatment they’re getting. In a double-blinded study, neither the patient nor the doctor knows which treatment is being used. Not knowing what you’re getting can be hard. Your doctor can always find out which group you’re in if there’s an important medical reason (such as a possible drug reaction), but it may result in your being removed from the study. Blinding reduces the risk that the doctor or patient’s beliefs about the new treatment will affect their evaluation of response or side effects.

Will my information be kept confidential?

As much as possible, your personal and medical information will be kept confidential. Of course your cancer care team needs this data to give you the best possible care, just as they would if you were not in a clinical trial.

Information that’s needed for the clinical trial, such as test results, is put on special forms and into computer systems. This is only shared with the people who analyze the study results. Your data is given a number or code – your name isn’t on the forms or in the study system. Sometimes, members from the research team or from the FDA might need to look at your records to be sure the data they were given is correct. But your personal information isn’t given to them and is never used in any published clinical trial results.

What about cost? Will my insurance cover it?

In most cases, the study sponsor provides the new treatment at no cost and pays for any special tests or extra doctor visits. Some sponsors may pay for more. For example, some might pay you back for travel time and mileage. It’s important to find out what will be paid for before you decide to get involved in any clinical trial.

The Affordable Care Act requires that health insurance covers the routine patient care costs for people who are in approved clinical trials. “Routine patient care costs” are costs that would normally be covered for anyone being treated for your kind of cancer. Insurers are not allowed to drop or limit coverage because a person chooses to take part in a clinical trial. This applies to all clinical trials unless the insurance plan is “grandfathered.” (Grandfathered plans are those that a person was enrolled in on or before March 23, 2010 and which has not decreased benefits or increased costs.)

The law requires insurance coverage for phase I, II, III, or IV clinical trials related to prevention, detection, or treatment of cancer or other life-threatening disease if the clinical trial meets one of these requirements:

  • It’s federally funded (any US federal agency such as the National Cancer Institute, Centers for Disease Control, Department of Defense, etc.)
  • It’s covered under an investigational new drug application (IND) that’s reviewed by the FDA
  • It’s does not need an IND application.

Insurers do not need to pay for:

  • The treatment, device, or service that’s being studied. This is usually paid for by the trial’s sponsor
  • Items and services only needed for data collection and analysis and not used in direct patient care
  • Any service that’s clearly not in line with standards of care for a certain type of cancer. This is why it is important to know what the clinical trial may not pay for so you can check if your insurance will.

Medicare coverage for clinical trials

If you have Medicare, it pays for many of the routine patient care costs for people with cancer who are in approved clinical trials. This is true no matter where in the United States you live. Medicare normally covers any cancer care when it’s part of either:

  • A clinical trial for the diagnosis and treatment of cancer; or
  • A clinical trial funded by the National Cancer Institute (NCI), NCI-Designated Cancer Centers, NCI-Sponsored Clinical Trials Cooperative Groups, or another federal agency that funds cancer research

If you’re not sure if your trial meets all the requirements, discuss these concerns with your doctor or call Medicare (1-800-633-4227).

Medicaid coverage for clinical trials

As of January 1, 2022, a new law requires that all state Medicaid plans cover the routine patient care costs for members who are in qualifying clinical trials.

Cancer clinical trials must meet certain criteria to be a qualifying clinical trial. Clinical trials must focus on the prevention, detection, and treatment of cancer or another life-threatening disease. The clinical trial must also be approved, done by, or paid for by certain government agencies or other accepted group.

If you're not sure whether the trial you're considering is a qualifying clinical trial, talk with your doctor or contact your state Medicaid agency.

What you can do to find out more about costs

Gather as much information as you can about the clinical trial and contact your insurance provider to find out about payment. Many insurers may not be able to give you a simple yes or no answer, because they may review claims on a case-by-case basis. They’ll also want to be sure that the doctors supplying the main part of your cancer care are “in network.”

If your insurance will not pay for parts of the clinical trial, ask your doctor or the research coordinator about other options. Sponsors may be willing to cover some of the costs your insurance does not.

Should I agree to take part in a clinical trial?  

This can be a very tough question. The answer won’t be the same for everyone. When trying to decide, first ask yourself some questions.

  • Why do I want to take part in a clinical trial?
  • What are my goals and what do I expect if I decide to take part? How realistic are these?
  • How sure are my doctors about my future if I decide to take part (or not take part) in this clinical trial?  
  • Do I have all the information I need to make an informed decision?
  • Have I weighed the benefits against the risks?
  • Have I thought about other factors, such as travel, time, and money?
  • Have I looked at my other options?

Some of these questions may not have clear answers but should help you start thinking about these issues. Each person’s situation is unique, and each person’s reasons for wanting or not wanting to take part in a trial may be different.

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.

Center  for Information and Study on Clinical Research Participation. Important Information: FAQ’s. Accessed July 31, 2020.

Chino F., Zafar SY. Financial toxicity and equitable access to clinical trials. Am Soc Clin Oncol Educ Book. 2019;39:11-18.

Centers for Medicare & Medicaid Services. Medicare and Clinical Research Studies. Revised September 2019. Accesses July 31, 2020.

US Department of Health and Human Services. About the Affordable Care Act.  Reviewed October 23, 2019. Accessed at July 31, 2020.

National Cancer Institute. Clinical Trials Information for Patients and Caregivers. Reviewed February 6, 2020. Accessed July 29, 2020.

National Institutes of Health. NIH Clinical Research Trials and You. Reviewed October 20, 2017. Accessed July 29, 2020.

Last Revised: August 22, 2022

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