Clinical Trials – Information for Participants

Clinical trials are the foundation of most medical advances. Without clinical trials, many of the medical treatments and cures we have today wouldn’t exist.

By testing new treatments and interventions in a carefully designed and controlled way, researchers learn more about the underlying mechanisms of disease and develop new ways to diagnose, treat, and prevent illness.

The results of clinical trials help inform medical decision-making and provide evidence-based information about the benefits and risks of different treatments or interventions. Researchers and doctors use this information to decide which treatments should be recommended and which require more study.

People volunteer for clinical trials for many reasons. Some people join clinical trials to help doctors and researchers learn more about a disease and improve health care. Other people, such as those with health conditions, join to try treatments that aren’t widely available.

Researchers usually study people who have a specific health condition. Researchers sometimes need to compare data from volunteers with no health conditions to data from people with specific health conditions so they can use that information to learn more about the disease.

Participating in a clinical trial is entirely up to you. If you volunteer for a clinical trial and later decide it’s not right for you, you can withdraw anytime.

Clinical Research Trials and You: Questions and Answers

Find more information about the risks and benefits of joining a clinical trial, how your safety is protected, and what happens when a clinical trial ends.

Download this free fact sheet about clinical trials

During a clinical trial, you will see a team of researchers, sometimes called a study team, clinical trial team, or clinical research team, who will monitor your health closely.

You may have more tests and medical exams than you would if you were getting mental health care but not participating in a clinical trial. The study team may also ask you to do other tasks, such as keeping a log about your health or filling out forms about how you feel.

Clinical trials occur in medical centers, doctors’ offices, and community-based organizations nationwide. You may need to travel or stay in a hospital to participate in a clinical trial.

Clinical trials are generally safe. Though there are risks to participating in clinical research, clinical trials are designed to minimize risks and keep you safe.

Before a clinical trial can start, it must be reviewed and approved by an institutional review board (IRB) for U.S.-based studies or an independent ethics committee outside the U.S. This review ensures that it is safe and that the potential benefits of the trial are worth the potential risks. The study team will also make sure you meet certain requirements and that it is safe for you to participate.

Clinical studies might make you feel a little uncomfortable for a short time, but how much risk you face depends on the type of study you join. For instance, if you are participating in a study testing a new drug, the medication might make you feel sick or tired when you first start taking it. In some studies, instead of trying a new medicine, you might take computer-based tests or have a non-invasive magnetic resonance imaging (MRI) done, which carries different risks. The research team and the IRB continuously monitor studies to ensure ongoing safety.

Speak with the study team to understand the risks involved in a particular study. Potential risks are included in the informed consent process, and the research team will be able to explain anything you don’t understand.

Some clinical trials pay participants, including some trials that take place at the National Institutes of Health (NIH) Clinical Center in Bethesda, MD.

The amount of money you get paid depends on things like how long the trial takes, how much time you need to give, and what kind of trial it is. Sometimes, the trial may also cover your travel, lodging, and food costs. Not all clinical trials are paid, and you should consider all aspects of the study, including risks and benefits, before making a final decision.

The National Institute of Mental Health (NIMH) is the lead federal agency for research on mental disorders. NIMH supports clinical trials at the NIH campus in Bethesda, MD and across the United States.

Find a study at the NIH campus

NIMH researchers conduct many clinical trials at the NIH Clinical Center . Located on the NIH campus in Bethesda, Maryland, the Clinical Center is the largest research hospital in the world.

Learn more about how to join an NIMH clinical trial at the NIH Clinical Center. These studies enroll volunteers from the local area and across the nation.

Find NIMH clinical trials for adults and children that are currently accepting volunteers:

• Join a Research Study: Adults
• Join a Research Study: Children
• Frequently Asked Questions About Participating in NIMH Research Studies for Adults & Children

You can also subscribe to receive email updates  about clinical trials conducted at NIH.

Find other studies around the United States

NIMH also funds many studies that are currently recruiting people around the country on different mental health disorders. To find a clinical trial near you, search clinicaltrials.gov , a database of privately and publicly funded clinical studies.

Other ways to find a clinical trial

• Talk to your health care provider about studies that may be right for you. You can also learn about studies in newspapers, TV, or online.
• Join a national registry of research volunteers, such as ResearchMatch . ResearchMatch is a nonprofit program funded by NIH that helps connect people interested in research studies with researchers from medical centers across the United States.
• Join the NIH All of Us Research Program , which is enrolling a large group of people that reflects the diversity of the United States. The program aims to build a diverse database that can inform thousands of studies on various health conditions.

After you find a clinical trial you're interested in, contact the study team to learn more about it. You can usually find the study teams’ contact information in the trial’s description. The staff can give you information that will help you decide whether to participate.

Check out this resource from the U.S. Department of Health and Human Services (HHS) for a list of specific questions to ask about volunteering for a research study .

Let your health care provider know if you decide to join a clinical trial. They may want to talk to the study team to help coordinate your care and ensure the trial is safe for you.

Federal resources

• Clinical Trials : The National Institute on Aging offers articles about how clinical trials work and how to participate about clinical trials.
• NIH Clinical Research Trials and You : Answers from the NIH to many common questions about participating in a clinical trial
• Clinical Trials  (MedlinePlus - also en español) : Information about clinical trial protocols and institutional review boards
• Federal Government Health Insurance Programs : Information about federal programs that help pay the costs of care in clinical trials

Videos

• NIH:
  • NIH Clinical Research Trials and You: Personal Stories : Stories about volunteers and researchers
  • Videos sobre la investigación clínica : Spanish-language videos about participating in research
• National Library of Medicine:
  • What is a clinical trial?  
  • Should I participate in a clinical trial? What’s in it for me? 
  • What should I know to participate in a clinical trial? 
• HHS: Human Research Volunteer Informational videos : Basic information about research, including questions to ask and what to think about when deciding whether to participate in a study

Last reviewed: April 2024