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NIH MedlinePlus the Magazine, Trusted Health Information from the National Institutes of Health

Clinical Trials: A Crucial Key to Human Health Research

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Photo: PhotoDisc

At the forefront of human health research today are clinical trials—studies that use human volunteers to help medical professionals observe and test new treatments for a wide array of health products and practices


A clinical trial is a research study designed to answer specific health questions by using human volunteers to help test those answers. Carefully conducted clinical trials are the fastest and safest way to find treatments that work in people, and there are clinical trials going on all the time in virtually every area of medical research. People who volunteer to take part in clinical trials do so for several reasons, including the chance to play a more active role in their own health care, gain access to new research treatments before they are widely available and help others by contributing to medical research.

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Photo: PhotoDisc

There are several different kinds of clinical trials, including:

  • Treatment trials to test experimental treatments, new combinations of drugs or new approaches to surgery or radiation therapy.
  • Prevention trials that look for better ways to prevent disease in people who have never had the disease, or to prevent a disease from returning. These approaches may include medicines, vitamins, vaccines, minerals or lifestyle changes.
  • Diagnostic trials to find better tests or procedures for diagnosing a particular disease or condition.
  • Screening trials that test the best way to detect certain diseases or health conditions.
  • Quality of Life trials (or Supportive Care trials) that explore ways to improve comfort and the quality of life for individuals with chronic illnesses.

How to Participate

Clinical trials are sponsored or funded by a variety of organizations or individuals, such as physicians, medical institutions, foundations, voluntary groups and pharmaceutical companies, in addition to federal agencies such as the NIH, the Department of Defense (DOD) and the Department of Veterans Affairs (VA). Trials can take place in different locations, such as hospitals, universities, doctors' offices and community clinics.

If you would like to participate in a clinical trial, you can find opportunities and more information at government Web sites such as:

The latest and most complete information about clinical trials today is available at the ClinicalTrials.gov Web site (http://clinicaltrials.gov). This is a free, confidential online resource from the National Institutes of Health (NIH), which anyone with a computer and Web browser can tap into for a comprehensive listing of clinical studies—in the U.S. and abroad—sponsored by the NIH and other federal agencies, pharmaceutical companies, universities and nonprofit organizations.

Here's how it works. After you enter the ClinicalTrials.gov Web site, you can search for a trial by the name of the disease, the location of the study, the type of treatment or the sponsoring institution. The results will show you what studies are under way, whether a trial is actively recruiting, the purpose of the study, where and when it will take place and whom to contact for more information.

"From the very beginning, ClinicalTrials.gov has been designed for use by patients," observes Donald Lindberg, M.D., director of the National Library of Medicine (NLM), the coordinating agency for NIH. "With patients taking an increasingly active role in their own healthcare, they now have a chance to learn more about clinical studies on everything from Alzheimer's disease to zinc supplementation. Without question, it has helped investigators with their research recruiting efforts, too."

Launched in February 2000, ClinicalTrials.gov currently contains information on more than 27,000 trials. The site has proven very popular with the public, logging approximately 8 million page views monthly and hosting over 20,000 visitors daily. The site is updated regularly, with new information added every day.

ClinicalTrials.gov has many helpful features for the consumer. If you are checking out trials on breast cancer, for example, the site also links you to the NLM's MedlinePlus (www.medlineplus.gov), with in-depth information on the topic, including recent news articles and an interactive tutorial. ClinicalTrials.gov also points you to NLM's Genetics Home Reference site (www.ghr.nlm.nih.gov), helping you understand possible genetic factors that can increase the incidence of the disease. It allows you to search medical journal references via NLM's PubMed (www.pubmed.gov) and links to the National Cancer Institute (www.nci.nih.gov), the lead NIH institute on this particular topic.

"It's really one-stop shopping, allowing the user to dig deeper for information on the disease or condition after viewing the list of clinical trials," says Dr. Lindberg. "ClinicalTrials.gov is a powerful tool for the individual health care consumer, and it has untold benefits for the public health, too, as new drugs and therapies evolve from these important studies."

Summer 2006 Issue: Pages 4 - 5