Making the Decision About Clinical Trials

Should I think about taking part in a clinical trial?

This is one of the toughest questions for many people with cancer. The answer won’t be the same for everyone. When trying to decide, first ask yourself some basic questions:

  • Why do I want to take part in a clinical trial?
  • What are my goals and expectations if I decide to take part? How realistic are these?
  • How sure are my doctors about what my future holds if I decide to participate (or not to participate?)
  • Have I considered the chance of benefits versus the risks?
  • Have I considered other possible factors, such as travel, time, and money?
  • Have I considered my other possible options?

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

Risk versus benefit

Each clinical trial offers its own opportunities and risks, but most have some things in common.

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 condition in the future by helping to advance cancer research.
  • You could have access to treatment that’s not otherwise available, which might be safer or work better than current treatment options.
  • You may increase the total number of treatment options available to you, even if you haven’t yet had all of the standard treatments.
  • You may feel you have more control over your situation and are taking a more active role in your health care.
  • You’ll probably get more attention from your cancer care team and more careful monitoring of your condition and the possible side effects of treatment if you take part in a clinical trial.
  • Some study sponsors may pay for part or all of your medical care and other expenses during the study. (This isn’t true for all clinical trials. Be sure you know who’s expected to pay for your care before you enroll in the study.)

Some of the possible downsides of being in a study can include:

  • The new treatment may have unknown side effects or other risks, which may or may not be worse than those from existing treatments. This is especially true of early phase trials.
  • As with other forms of therapy, the new treatment may not work for you even if it helps others.
  • There may be inconveniences such as more frequent office visits and testing, as well as time and travel commitments.
  • 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 (although this information is available if needed for your safety).
  • Insurers may not cover all of the costs of taking part in a clinical trial, but they usually cover the costs of what would normally be standard care. Be sure to talk to your insurance provider and someone involved with the study before you decide to take part, so you know what you may have to pay for.

Common concerns about clinical trials

Most people have some concerns about taking part in a clinical trial, often because they’re not really sure what it will mean for them. Taking the time to get as much information as you need before you decide is the best way to be sure that you make the choice that’s right for you.

Will there be risks?

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

Perhaps a more important question is whether 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 realistic about what this chance is. Ask your doctor to give you an idea of what the possible benefits are, and exactly what benefit is likely for you.

With this in mind, you can make a more informed decision. 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?”

There’s no denying that the ultimate purpose of a clinical trial is to answer a medical question. People who take part in clinical trials may need to do certain things or have certain tests done to stay in the study.

But this doesn’t mean that you won’t get excellent, compassionate care while in the study. In fact, most people enrolled in clinical trials appreciate 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 comfortable with your decision.

Will I get a placebo?

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 if it would deny the person a chance to get a drug that’s known to work.

Unfortunately, there are some types of cancer for which there are no proven effective treatments. 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 standard of care already being used.

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

Not for studies that are randomized. This means that each person who takes part in the study gets assigned randomly to either the treatment group or the control group. Randomization is used to help reduce the chance that one group will be different from the other when they go into the study, which could affect outcomes. This is especially helpful to make sure that the groups have people in similar states of health, so the results are not skewed in favor of one group. If people were allowed to choose which treatment they got, the study results might not be as accurate. For example, people who were sicker might tend to choose one treatment over the other. If the new treatment was then found not to work as well, doctors couldn’t be sure if this was because the treatment wasn’t as good or because it was tested in sicker people.

Often people have a 50:50 chance of ending up in one group or the other. In some cases, the study may allow for a different ratio, such as 2 out of 3 people getting the new treatment and only 1 out of 3 getting the standard treatment.

Some people find the concept of randomized studies distressing, since neither the patient nor the doctor can choose which group the patient is in. This can be especially true if a study is looking at 2 totally different treatments and a person sees one as 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 form of 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 doctors will be biased in their evaluations of the patients’ outcomes. These controls help make the study results more reliable.

Will my information be kept confidential?

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

Medical information that’s important for the study, such as test results, is usually put on special forms and into computer databases. This is then given to the people who will analyze the study results. Your information is assigned a number or code – your name isn’t on the forms or in the study database. Sometimes, members from the research team or from the Food and Drug Administration might need to look at your medical records to be sure the information they were given is correct. But your personal information isn’t given to them and is never used in any published study results.

Questions to ask before joining a clinical trial

Each clinical trial is unique, with its own possible benefits and risks. Before you decide to take part in one, you may want answers to these questions. Some people take notes, record discussions, or bring a friend with them to help recall the answers and think of other questions:

  • Why is this study being done?
  • What’s likely to happen if I decide to take part or decide not to take part in the study?
  • Will the researchers work with my cancer doctor? Who will be in charge of my care?
  • Who will I contact if I have problems, questions, or concerns?
  • What are my other options (standard treatments, other studies)? What are their pros and cons?
  • How much experience do you have with this particular treatment? With clinical trials in general?
  • What were the results in earlier studies of this treatment? How likely are they to apply to me?
  • What kinds of treatments and tests would I need to have in this study? How often are they done?
  • Will this require extra time or travel on my part?
  • How could the study treatment affect my daily life?
  • What side effects might I expect from the study treatment? Are there other risks? (Keep in mind that there can also be side effects from standard treatments and from the disease itself.)
  • How will we know if the treatment is working?
  • Will I have to be in the hospital for any parts of the study? If so, how often, for how long, and who will pay for it?
  • Will I still be seeing my regular cancer doctor? Who will be in charge of my care during the study?
  • Will I have to pay for anything? Will any of the treatment be free? 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 study? How long will the study last?
  • Are there reasons I would be removed from the study? Are there reasons the study might be stopped early?
  • Is long-term follow-up care part of the study? What would it involve?
  • If the treatment is working for me, can I keep getting it even after the study ends?
  • Can I talk to other patients already taking part in the study?
  • Will I be able to find out about the results of the study?
  • How long do I have to make this decision?

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 making a decision that’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 one 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 journalists, editors, and translators with extensive experience in medical writing.

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Centers for Medicare & Medicaid Services. Clinical research studies. Accessed at on May 4, 2016.

Centers for Medicare & Medicaid Services. Should you join a clinical research study? Accessed at on May 4, 2016.

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National Cancer Institute. Patient Safety in Clinical Trials. Accessed at on May 2, 2016.

National Cancer Institute. Questions to Ask Your Doctor about Treatment Clinical Trials. Accessed at on May 4, 2016.

Stryker JE, Wray RJ, Emmons KM, Winer E, Demetri G. Understanding the decisions of cancer clinical trial participants to enter research studies: factors associated with informed consent, patient satisfaction, and decisional regret. Patient Educ Couns. 2006;63(1-2):104-109.

Last Medical Review: May 3, 2016 Last Revised: May 3, 2016