What does it mean to be randomized?

In randomized clinical trials, a computer randomly divides patients into separate groups that are given different treatments or interventions (for example, one group is given a new experimental treatment and another group an approved standard treatment). The patients are separated by chance, which means that if you participate in a randomized study, you and your doctor will not be able to choose which treatment you receive. Dividing participants into groups randomly means that the groups will be similar and the different treatments or interventions can be compared more fairly.

You can read more about the types of clinical trials here and about how patients are protected in randomized clinical trials here.

What is informed consent?

Once you find a clinical trial that may be appropriate for you, you go through a formal, regulated process called informed consent. During this process, the research team will explain all relevant information about the trial’s purpose, risks, benefits, alternatives, and procedures to you as a potential participant. This information will be provided in an informed consent document that is clearly written in language that is easy to understand. The informed consent process is required for all clinical trials so that you can then make an informed decision about whether or not to participate, considering your own personal interests and circumstances. You also have the opportunity to ask the research team any questions that you have during the process.

If you decide to participate in a clinical trial, the informed consent process continues throughout the trial – the research team will update you about any changes to the study or new information about risks and benefits of the treatment that emerge.

You can read more about informed consent and other patient protections here.

What is the difference between clinical research, a clinical trial, and a clinical study?

Clinical research is the study of people, or their data or samples (for example, tissue samples), to understand something about health and disease. A clinical study involves research using human volunteers that is intended to add to medical knowledge. The terms clinical study and clinical trial are often used interchangeably – but as noted elsewhere in this section, a clinical trial, per the NIH, involves an intervention and measures a health or behavioral outcome. These web pages focus on interventional clinical trials.

You can read more about the different types of clinical trials here.

Did You Know…

Most of the time, when you take part in a clinical trial, you will only be in that one phase of the study. Treatments move through the phases, but patients do not.

Did You Know…

All patients in clinical trials are volunteers. You can choose to quit a clinical trial at any time, but talk to your doctor first. Your doctor can tell you how quitting the trial might affect your health and if there are other treatment options. Your relationship with your healthcare providers will not be changed by your decision.

What questions do I ask before participating in a clinical trial?

You will want to find out as much as possible about a clinical trial before deciding to participate so that you can make an informed decision. Some of your questions may be answered in the informed consent document. You should feel comfortable asking your healthcare and research team any other questions you have about the study. For example, you may have questions about the risks or side effects that you may experience, the possible benefits you can expect, what other treatments are available, and what types of procedures or tests you may need. You may also want to discuss questions about costs and where you will need to go for treatment.

It may help to jot down your questions before your doctor’s visit so that you are prepared.

Are older participants important in clinical research?

People of all ages are important in clinical research to understand how a treatment works across the population. Different clinical trials have different eligibility criteria, including age requirements, so not all patients will be able to participate in a given trial. For example, separate trials are sometimes conducted in adults and children. Some clinical trials exclude patients above a certain age, who may be more likely to experience side effects or have other conditions that could impact treatment outcomes. Sometimes separate trials are conducted in older patients, especially when a different dosage may be needed.

If you have found a clinical trial that you are interested in joining, talk to your doctor to see if you are eligible to participate. Your doctor and/or the clinical research team can review the eligibility criteria including any age-related criteria.

What if I change my mind after I agree to be in a clinical trial?

People who volunteer for a clinical trial can withdraw from the study at any time, for any reason, even if the study has not yet completed. It is a good idea to discuss your decision to withdraw from a clinical trial with your doctor so they can discuss how this may affect your health.