Informed Consent
If your health care team recommends that you get certain procedures or treatment, you have the right to receive certain information and ask questions before agreeing.
Informed consent is the process through which your health care team makes sure you understand the treatment or test they recommend for you. The suggested medical care shouldn’t begin unless you give informed consent. This allows you to make the best decisions about your care.
Learn more about what is required for informed consent and common questions people have about this process.
What is needed for informed consent?
The informed consent process is meant to help you weigh all the pros and cons of a procedure or treatment and make the best choice for yourself. The main purpose of the informed consent process is to protect you. Your health care team should provide you with the following information:
- The name of your disease or condition
- The name of the procedure or treatment that is recommended for you
- Risks and benefits of the treatment or procedure
- Other treatment options including their risks and benefits
- Risks of not getting the treatment or procedure
Shared decision-making
Shared decision-making is part of the informed consent process. It’s when decisions about your care are made with you, rather than someone making the decisions for you. These decisions should reflect your preferences, personal values, opinions, and goals for your health. This type of decision-making is especially helpful when there is no single "best" treatment option.
Your health care provider should work with you to decide the best way to give you the information you need. If the health care team uses terms you don’t know, ask them to explain those terms. If your first language is not English, you should be given this information in your preferred language, or you can ask for a translator.
The provider may choose to use methods other than a verbal discussion or a written document, like videos, interactive computer modules, audio files, or other methods to help you understand the information better. Be sure you understand all the information given, even if it means going over it many times or asking your provider to explain it in different ways. Your health care team should also ask if you have questions or don’t understand something.
Making the right decision for you
Take time to think about what you’ve been told. You might want to talk with your loved ones and trusted friends before you make a decision. You don’t have to decide right away. You also might want to have a family member or friend come with you for these discussions to help you remember what questions you have and what your health care team said.
If you need extra time to review the information, ask your health care provider for a copy of the informed consent form or other information. This way you can take it home and review it as many times as you need before deciding.
Your decision needs to be based on your preferences and values. Don’t feel like you have to agree to a procedure or treatment just because someone else, like your health care team or your family, thinks you should. Try to make the decision based on what you want.
If you don’t understand the forms you are asked to sign, don’t be afraid to let someone know 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.
Signing an informed consent form
When you sign an informed consent form, you are stating that you:
- Received all the information about your treatment options from your health care provider.
- Understand the information, have had a chance to ask questions, and have had the time to make a choice for yourself.
- You do not feel pressured to make a decision based on what other people want.
- Based your decision on whether to receive the procedure or treatment on this information. Sometimes, you may choose to receive only part of the recommended care. Talk to your health care provider about your options.
- You give your consent (agree) to receive all or some of the treatment options. The completed and signed form is a legal document that lets your doctor go ahead with the treatment plan.
If you don’t understand the forms you are asked to sign, don’t be afraid to let your health care team know. 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.
After you sign the consent form, someone in the room with you will need to sign as a witness.
When is informed consent needed?
The informed consent process might begin even before you are diagnosed with cancer. You might need to sign consent forms for tests to figure out if you have cancer.
The informed consent process for cancer treatment might be more detailed. If you are getting more than one treatment, you will probably need to sign separate consent forms. For example, if you will first have surgery to remove your cancer and then will have radiation afterwards, you will need to give consent for both surgery and radiation.
Some medical treatments and procedures that you might have to give written informed consent for include:
- Surgery
- Radiation
- Medicines to treat your cancer, like chemotherapy, targeted therapy, immunotherapy, and hormone therapy
- Stem cell or bone marrow transplant
- Some medical tests and procedures, like a biopsy (removing cells from a suspicious area so that they can be looked at in the lab to see if cancer cells are present)
- Some vaccines
- Some blood tests, imaging tests, or procedures
- Clinical trials
Informed consent for a clinical trial or study is often more detailed than standard treatment. You will need to be given more information since the treatment may be newer and you might need to agree to more testing. You can learn more about this process in Being Part of a Clinical Trial.
Children and informed consent
For children or others who are not able to make the decision for themselves, a parent or legal guardian is responsible for getting the information, making the decision, and signing the consent form.
Sometimes older children who are being treated need to give assent (willingness to participate), even if their parents or guardian have agreed on the child’s behalf. Assent means that even though the parents sign the form, the child must also be okay with the plan before the treatment will be done.
Frequently asked questions about informed consent
There are times when the usual informed consent rules do not apply. This varies from state to state and may include:
- If you are unconscious and in danger of dying or other serious outcomes if you are not treated right away, informed consent may not be required before treatment.
- If health care providers who are giving treatment know that you have an advance directive stating that you don’t want certain types of care, a treatment may not be given.
- If a decision made by a parent or guardian of a child or an adult who is not able to make their own decision is challenged by a doctor or facility, the courts may review the situation.
- If the person does not want to make the decision themselves, they can ask the health care provider to make the decision.
- An older teen—for example, one who is self-supporting and doesn't live at home, is married, pregnant, or in the military—does not need parental consent.
In case you are not able to make decisions for yourself in the future, you might want to designate someone to be your health care proxy. (See Advance Directives for more detailed information on this process.) This person will legally be able to make decisions for you until you are able to make these decisions yourself.
If your decision-making ability is questioned or unclear, a psychiatrist may be asked to check whether you are able to make your own decisions. If you haven’t chosen a health care proxy, each state has laws about who might be asked to make decisions for you.
If no one can be found, the courts may be asked to appoint a surrogate or proxy for you. This is someone a judge chooses to make decisions for you if you become unable to make decisions for yourself.
Yes, you can change your mind at any time, even if you have already started treatment. Let your health care team know your wishes.
You have the right to refuse any and all treatment options. You may also choose other treatment options that have been presented to you by your health care team, even if they are not the one your health care provider recommends. You may also refuse part of the treatment options, without refusing all care.
For example, you may choose to refuse surgery, but still be treated for pain. If your health care provider is not comfortable with your choice, you may need to find another health care provider to treat you as you want.
If you decide you don’t want certain treatments or diagnostic tests, your health care team may tell you about the risks or likely outcomes of this choice. This way you can make an informed refusal. This means that you understand what could happen if you don’t get the recommended treatment. You might be asked to sign a form stating that you received this information and that you still chose not to be treated.
Treatment cannot be given without your consent unless you need emergency care and are unable to give consent. However, you have the right to refuse information and treatment. Or, in advance, you can assign a person to make decisions for you through an advance directive or other legal document.
You can also ask for minimal information and trust your health care provider to make decisions for you. At the same time, informed consent laws do not allow a health care provider to keep a diagnosis from you, even at your family's request.
- Written by
- References
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.
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Last Revised: July 25, 2025
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