The short answer
Informed consent is a process, not just a form. Before you join a trial, the research team explains its purpose, procedures, and possible risks and benefits, along with your other treatment options. You can ask questions, and you have the right to leave the trial at any time, even after signing.
Informed consent is a process where the research team explains the trial before you decide to join.
It covers the trial's purpose, procedures, possible risks and benefits, and your other treatment options.
You have the right to ask questions, to join, and to leave the trial at any time.
You have the right to hear and read the information in a language you understand.
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The full explanation.
More than a signature
Informed consent often gets pictured as a single moment — signing a form. In reality, it's a process that starts before you make a decision and continues for as long as you're part of a trial.
Before you're asked to decide anything, the research team walks you through what the trial actually involves. That conversation is meant to give you a full picture, not just a summary.
What the research team explains
During informed consent, you should hear clear information about:
- The purpose of the trial and what it's trying to learn.
- The procedures and tests involved, and what a typical visit or cycle might look like.
- Possible risks and possible benefits of taking part.
- All of your treatment options, including ones outside the trial.
- Details about the specific treatments or tests being studied.
This isn't a one-way lecture. You have the right to ask questions at any point, and the team should be willing to answer them in a way that makes sense to you.
Your rights throughout the process
Informed consent comes with a set of protections that stay with you the whole time you're considering, and participating in, a trial:
- The right to ask questions before deciding.
- The right to take part if you choose to.
- The right to leave the trial at any time — including after you've already signed the consent form.
- The right to hear and read the information in a language you understand.
None of these rights expire once you sign paperwork. If you change your mind a week, a month, or a year into a trial, you're allowed to stop.
The consent form itself
After your conversation with the research team, you'll receive a written consent form. It lays out everything that was discussed — purpose, procedures, risks, benefits, and your other options — so you can review it on your own time before deciding. If you agree to take part, you sign it.
Signing the form isn't the end of the conversation, though. As a trial continues, new information sometimes comes to light — about side effects, results, or anything else relevant to your decision to stay in the study. When that happens, the research team is expected to keep you informed, so you can decide whether you still want to continue.
When children are involved
Children under 18 aren't able to give informed consent on their own, since consent legally requires a certain level of understanding and independence. Instead, children may be asked to give assent, meaning they agree to take part, or they may dissent, meaning they decline. Depending on their age and understanding, children as young as 7 may be asked whether they assent or dissent, alongside a parent or guardian who provides consent on their behalf.
This approach respects a child's voice in the decision while still relying on a parent or guardian to formally consent.
Bringing questions of your own
Informed consent works best as a two-way conversation. If anything about a trial's purpose, procedures, risks, or your other options isn't clear, that's exactly what the informed consent process is there for — so don't hesitate to ask until you feel you understand what you'd be agreeing to.
Words to know
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Common questions
▸What is informed consent?
Informed consent is a process where the research team explains a clinical trial to you before you decide whether to take part. It covers the trial's purpose, procedures, possible risks and benefits, and your other treatment options.
▸Do I have to sign something to join a trial?
After the research team discusses the trial with you, you'll receive a consent form to read. If you agree to take part, you sign it. But informed consent is more than the form — it's an ongoing conversation.
▸Can I leave a clinical trial after I've signed the consent form?
Yes. You can leave a trial at any time, even after signing the consent form.
▸What if I don't speak English well?
You have the right to hear and read the trial information in a language you understand.
▸Can children join clinical trials?
Children under 18 cannot give informed consent themselves. Instead, they may give assent (agreeing to take part) or dissent (declining), sometimes starting as young as age 7, alongside a parent or guardian's consent.
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