Skip to main content

Clinical research involves clinical trials performed in humans that are intended to increase knowledge about how well a diagnostic test or treatment works in a particular patient population.

Clinical trials are research studies where people help doctors find ways to improve health and care. Each study tries to answer scientific questions and to find better ways to prevent, diagnose, or treat diseases.

The Neuroimaging & Child Psychiatry Research Center’s (NCPRC) researchers must follow specific guidelines to ensure study participants’ safety and privacy. Before a new treatment is tested in people, scientists perform studies in research labs, often carrying out experiments in animal and human cells.

Typically, testing in animals comes after these tests. NCPRC’s researchers do not conduct animal research. If the research is successful and safe in animals, the Food and Drug Administration (FDA) can approve the treatment for testing in humans.

Researchers must also design a study protocol. This is a plan and outline that maps out the criteria for participation, schedule of procedures and treatments, and length of the study.

The researchers also design a consent form for study participants to sign providing their permission to be in the study.

The University of Utah has an Institutional Review Board (IRB) that reviews and approves the protocol, consent form, and all other documents for each study. In addition, the IRB re-evaluates each study at least yearly while the study is active. To receive approval from the IRB, researchers must demonstrate how they plan to protect the rights of study participants and ensure that the study does not present undue risks to the participants.

Three Phases

Most clinical research that involves testing a new treatment progresses in phases. This allows researchers to ask and answer questions in a way that yields reliable information about the treatment and protects the patients.

Clinical trials are usually classified into one of three phases:

  1. Phase I trials are the first step in testing a new treatment in humans. In a phase I study, researchers evaluate how a new drug should be given (by mouth, injected into the blood, or injected into the muscle), how often, and what dose is safe.

    A phase I trial usually enrolls only a small number of patients, sometimes as few as a dozen. About 70 percent of experimental drugs pass this initial phase of testing.

  2. Phase II trials focus on evaluating how well a new treatment works. They also continue to test the safety of the treatment. The second phase of testing may last from several months to two years, and involves up to several hundred patients. About one-third of experimental drugs successfully complete both phase I and phase II studies.
  3. Phase III trials compare the results of people taking the new treatment with results of people taking standard treatment. Investigators usually assign participants to the standard treatment group or the new treatment group at random (called randomization).

    Phase III trials often enroll large numbers of people and may be conducted at many sites across the nation.