Clinical Trials (cont.)

Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• Clinical research and clinical trials facts
• What is clinical research?
• Why is clinical research important?
• What are clinical trials?
• What are the phases of a clinical trial?
• How can one find out what clinical trials are currently being conducted?
• How is a clinical trial performed, and what sort of preparation is needed?
• What is informed consent?
• Is patient privacy maintained in a clinical trial?
• Who can participate in a clinical trial?
• Are people paid for participating in clinical trials?
• What are the pros and cons of participating in a clinical trial?
• Can a person leave a clinical trial once it has started?
• Who sponsors clinical trials?
• What happens after a clinical trial is completed? Is there follow-up care?
• Clinical Trials Index

What is clinical research?

Clinical research is a type of study of clinical or biomedical questions through the use of human subjects. Clinical research studies do not necessarily all involve medical treatments or experimental therapies. Clinical research can include observational studies, in which people are followed over a period of time to determine health outcomes. Clinical research may also be used to determine the usefulness or safety of a new diagnostic procedure or drug treatment in the form of a clinical trial. Clinical research studies are planned in advance and follow a defined protocol. Epidemiologic studies examine specific populations to clarify the incidence and prevalence of diseases, the individual factors that can cause or worsen disease progression, and the types of health and lifestyle decisions that people make. Clinical trials (see below) are one important type of clinical research.

Why is clinical research important?

Clinical research is important in order to develop new therapies and diagnostic procedures as well as to understand how diseases develop. Observational studies may help identify risk factors for the development of a particular disease, such as the association between smoking and lung cancer. Outcomes-based research can help doctors identify the most effective therapies and treatments for a number of conditions. Another aspect of clinical research is the development of new technologies for use in health care, ranging from surgical tools and materials to hearing aids and artificial limbs.

What are clinical trials?

Clinical trials are a form of clinical research that follow a defined protocol that has been carefully developed to evaluate a clinical question. The U.S. National Institutes of Health (NIH) defines a clinical trial as

"a prospective biomedical or behavioral research study of human subjects that is designed to answer specific questions about biomedical or behavioral interventions (such as drugs, treatments, devices, or new ways of using known drugs, treatments, or devices)."

Although people commonly associate clinical trials with drug trials, in which new medications or combinations of drugs are tested for their effectiveness against a disease, clinical trials may also evaluate whether interventions such as counseling or lifestyle modifications have an effect on disease progression. Clinical trials may be conducted on people who have a disease or on healthy people, depending upon the purpose of the research.

The U.S. NIH describes the following types of clinical trials:

• Treatment trials test new treatments, new combinations of drugs, or new techniques in surgery or radiation therapy.
• Prevention trials are designed to identify ways to prevent disease through the use of medicines, lifestyle changes, dietary supplements such as vitamins, or immunizations.
• Diagnostic trials aim to identify improvements in tests or methods used to diagnose disease.
• Screening trials look for ways to detect specific conditions.
• Quality of life trials (also referred to as supportive-care trials) are trials that are designed to improve comfort and the quality of life for people suffering from chronic conditions or diseases.