Consent and Assent of Clinical Trial Participation

One basic principal of medical ethics is that no person should be included in any sort of experiment without his or her agreement. This agreement is called consent. In the past, heinous examples of medical experiments occurred where people were given injections of experimental drugs or even diseases without knowing it. However, since the Nuremburg trials in the 1940s and particularly since the 1970s, experimenting on people without their agreement and consent has been considered unacceptable in the U.S. and the rest of the civilized world.

Informed consent refers to the idea that not only should people know they are in a clinical trial, but that they also must understand what will happen to them during the trial.

Informed consent is a process that involves both talking to someone involved in running the trial to learn about the trial and signing a paper, called the consent form, that explains the trial. The process of informed consent should include:

  • What is known about the experimental treatment.
  • What will happen during the clinical trial, including what medicines will be taken, when and how they will be taken, and what and when tests or procedures will be done.
  • What parts of the trial are considered standard, i.e., they would happen even if you are not involved in the trial, and what parts of the trial are experimental. Experimental parts of the trial can be treatments, office visits, tests, etc.
  • What the alternative is to being in the trial and what the treatment and testing would be like if you do not participate in the trial.
  • Whether there will be any financial costs to participate in the trial.
  • Whether the trial is expected to benefit the participants personally or whether it is to benefit patients in the future.
  • Whom to contact if you have questions or complaints about the trial.
  • What the procedure is to stop participating in the trial.

All clinical trials are overseen by an Institutional Review Board (IRB), which is a group of scientists and non-scientists that ensure that clinical trials are done in an ethical manner. Each university or cancer center has its own institutional review board. The institutional review board approves all aspects of clinical trials, including what is included in a consent form. The consent form should have contact information for the institutional review board in case you ever feel uncomfortable with what is happening in a clinical trial.

Giving informed consent requires that someone has the mental capacity to understand his or her options and to make a rational and consistent choice. Some patients, such as children or people with mental impairments, are thought to need special protection because they may not understand enough to give informed consent. In that case, two things are needed. First, the person’s guardian, such as the parent for a child, must give informed consent. Second, if possible, the child or impaired person needs to agree to the trial, which is called giving assent.

If possible, the child or impaired person needs to agree to the trial, which is called giving assent.

Sometimes this is impossible, for example for young infants or people who cannot communicate. The age at which assent is required will vary from trial to trial, but national groups such as the American Academy of Pediatrics, and the Children’s Oncology Group recommend that children 7 years of age or older not be enrolled in clinical trials without their assent. Requiring assent allows a child to say no and to have some control over what happens to his or her body. Not only are uncooperative children difficult to get useful scientific results from, but some children may tire of participating in medical research before parents, who naturally hope for a miracle.