How Clinical Trials Are Conducted

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Clinical trials are usually conducted at cancer centers, universities, hospitals, or clinics. Most studies are available at local community hospitals. Exceptions arise if a very scarce piece of equipment is required by the study, or if the trial involves a new specialized technique familiar to only a few doctors.

The researchers who would like to conduct the clinical trial write a plan for how the trial will be done and what they hope to find out. This plan is known as a protocol. The protocol is a very technical document and contains details of the dosage level of each treatment that will be given, as well as how often and for how long each treatment will be given. The protocol also lists all the lab work and tests that will be done to figure out how each person in the trial is reacting to the treatment.

The protocol is reviewed by an institutional review board, which either approves or rejects the trial. The review board considers several questions when making its decision:

  • Is it ethical to ask people to volunteer for this experimental treatment?
  • Has the study been designed to make sure the people involved will be safe?
  • Will the participants receive a treatment that is at least as good as or better than what they'd get if they weren't in the study?

This review board is made up of scientists, physicians, and nurses who are not involved with the clinical trial. If the clinical trial is approved, the review board monitors the trial and formally reviews it each year.

After the protocol is approved, the researchers begin asking people to be part of the trial. Clinical trials usually have between one and four different treatment plans. In most cases, people who enroll in a clinical trial are randomly assigned to receive one of the treatment plans. This is called a "randomized" trial. Many clinical trials are "double-blinded." This means that neither the participant nor the researcher knows which treatment plan the participant is following. Double-blinded clinical trials help researchers see the actual benefits and side effects of a treatment without bias or outside influence. Bias in this context means any preconceived ideas about a treatment that could affect how you take the medicine, which in turn could influence the study results. The medicine that you receive is labeled with a code that is held in confidence by a small group of people not involved in your treatment. The code is revealed at the end of the study when the results are evaluated. Whenever possible, clinical trials are both randomized and double-blind.

A participant has to give what's called "informed consent" before joining a clinical trial. Informed consent requires researchers to explain the clinical trial's protocol to the potential participants. The researchers also must tell the potential participant of any possible risks and benefits of participating in the trial. A person can then decide whether or not to participate in the trial. It's also important to know that people can quit a clinical trial at any time.

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