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Home>Health>Genetics and Genomics for Patients and the Public>Genetic and Genomic Science and Research >Frequently Asked Questions About Clinical Research

Frequently Asked Questions About Clinical Research

What is clinical research?
What is a protocol?
What is a clinical trial?
What are clinical trial "phases?"
What are "blind" or "masked" studies?
Should you volunteer for clinical studies?
How do I find information about clinical trials for specific conditions?

What is clinical research?

Clinical research enables doctors and researchers to find new and better ways to understand, detect, control and treat illness. A clinical research study is a way to find answers to difficult scientific or health questions. For example, the study might explore the best ways to counsel people with a genetic mutation for colon cancer.

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What is a protocol?

All clinical studies are based on a set of rules called a protocol. A protocol describes what types of people are eligible to participate in the study; determines the schedule of tests, procedures, medications, and dosages; and sets the length of the study.

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What is a clinical trial?

If a clinical research study involves testing or studying a drug or medical device to see if it is a safe and effective treatment for people, it is called a "trial." For example, a clinical trial may test the effectiveness of a new drug for treating Parkinson's disease.

Many new medicines and drugs are found to work in the researcher's lab, and to be safe and effective in animal tests. But drugs and devices must be proven to be safe and effective for people before the Food and Drug Administration (FDA) can approve them and doctors can prescribe them. The FDA has strict rules that govern how clinical trials are conducted. These rules are designed to ensure the safety of those who participate.

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What are clinical trial "phases?"

Clinical trials of experimental drugs proceed through four phases:

In Phase I clinical trials, researchers test a new drug or treatment for the first time in a small group of people - about 20 to 80 - to evaluate its safety, determine a safe dosage range and identify side effects.

In Phase II clinical trials, the study drug or treatment is given to a larger group of people, about 100 to 300, to see if it is effective and to further evaluate its safety.

In Phase III studies, the study drug or treatment is given to large groups of people - from 1,000 to 3,000 - to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.

Phase IV studies are done after the drug or treatment has been marketed. These studies continue testing the study drug or treatment to collect information about its effect in various populations and gather data on any side effects associated with long-term use.

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What are "blind" or "masked" studies?

In many clinical trials, one group of patients will be given an experimental drug or treatment, while a control group is given either a standard treatment for the illness, or a placebo (a harmless "fake" drug), or no treatment at all.

In a blinded or masked study, participants do not know whether they are getting the drug being tested, or whether they are in the control group. Sometimes, clinical trials are "double-blind" or "double-masked." That means that neither the participants, nor the study staff members know who is receiving the experimental treatment and who is in the control group receiving either a standard treatment or a placebo. Studies are performed in this way so that neither the patients' nor the doctors' expectations about the experimental drug can influence the results.

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Should you volunteer for clinical studies?

Clinical studies are a vital part of finding new treatments and cures for diseases. Carefully conducted clinical trials are the fastest way to find treatments that work and that are safe. By volunteering for a clinical trial, you are participating in research that may result in a new treatment for a deadly or debilitating disease.

Before you agree to participate in a study, you must be given complete information about the study, known as "informed consent." The informed consent must include information about the purpose of the research as well as possible benefits and risks. The Food and Drug Administration (FDA) provides details about informed consent with the information page: Clinical Trials of Medical Treatments: Why Volunteer? [fda.gov].

Because participating in a trial is an important decision, there are many questions that you should consider before agreeing to participate. The Centers for Disease Control (CDC) has prepared a list of questions, Taking Part in Research Studies: What Questions Should You Ask? [cdc.gov], that can help you get the information you need to make a decision about participating.

Clinical Research at NHGRI

Researchers at the National Human Genome Research Institute (NHGRI) are developing advanced methods for studying the fundamental mechanisms of inherited and acquired genetic disorders. Their goals include both discovering the molecular basis of human genetic diseases, and creating new technologies to accelerate further genetic research.

NHGRI investigators are working to uncover the genetic components of common disorders such as cancer, diabetes and heart disease, as well as lesser known conditions such as Pallister-Hall Syndrome and Proteus Syndrome.

To that end, NHGRI scientists often study families with a history of inherited diseases. This helps to unravel the complex roles that multiple genes and environmental factors play in disease. Such studies will enable the development of effective and reliable gene-based diagnostic tests, and can lay the foundation for genetic treatments.

Additional Information About Clinical Trials

An Introduction to Clincial Trials [clinicaltrials.gov]
Comprehensive information about participating in clinical trials, including how they work, what patients should know, what are the benefits and risks, and how volunteers are protected. Hosted by the National Institutes of Health (NIH) and the National Libraries of Medicine (NLM).

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How do I find information about clinical trials for specific conditions?

  • Current NHGRI Clinical Studies
    A listing of NHGRI investigators' clinical studies that are currently recruiting.

  • ClinicalTrials.gov
    A comprehensive database of about 5,700 current clinical studies sponsored by the federal government and the pharmaceutical industry. Search by disease, treatment, sponsor or keyword. Hosted by NIH and the NLM.

  • Search the Studies at NIH [clinicalstudies.info.nih.gov]
    Database of all clinical studies being conducted at the NIH Clinical Center, Bethesda, Md. Search by diagnosis, signs and symptoms, or key words or phrases.

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Last Reviewed: February 20, 2009




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See Also:

Talking Glossary
of Genetic Terms

Definitions for genetic terms found on this page

Current NHGRI Clinical Studies

Clinical Research
Program Overview

On Other Sites
ClinicalTrials.gov: Search for current clinical trials.



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