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Clinical Trials (cont.)

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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 before the patient has any symptoms of the disease.
  • 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.
Medically Reviewed by a Doctor on 11/4/2016


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