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Questions About Clinical Research

Clinical Research

What is clinical research?
MRIClinical research enables researchers and doctors to find new and better ways to understand, detect, control and treat human diseases. A clinical research study is a way to find answers to difficult scientific or health questions. For example, a clinical study might be conducted to identify what causes people to get a disease (observational study) or test whether a new treatment, surgical procedure or lifestyle change can cure or prevent a disease from occurring (interventional study).

Who can participate in a clinical research study?
All clinical research studies have guidelines called inclusion/exclusion criteria that determine who can participate. These guidelines are based on such factors as age, type of disease, medical history, current medical condition and exposure history. These criteria are used to identify appropriate participants and keep them safe as well as to ensure that researchers will be able to answer the questions being asked.

What is the difference between an observational clinical research study and a clinical trial?
Some clinical research studies are purely observational. Although the subjects may be required to donate a blood specimen or undergo a diagnostic procedure, no treatment will be administered to them to try to change the course of their disease. In this type of study, data will be collected from the subjects through clinical testing or questionnaires. The data will be analyzed to try to determine what caused the disease or why some people are more likely to develop it than others. Blood is often collected to test for a genetic predisposition for the condition. Different types of data are collected to determine what other factors might have contributed to the disease. Examples of some of the types of data that might be collected for an observational clinical research study include family, medical, occupational and geographical history, ethnicity, toxicant exposure, diet and lifestyle.

If a clinical research study involves studying a drug, a new medical procedure or device, it is called a clinical trial. For example, a clinical trial may test the effectiveness of a new drug for treating diabetes or asthma. 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 they can be routinely used in people.

What are the benefits to me if I participate?
The benefits to you depend on the particular study you participate in. The largest benefit by far is that you are helping others with similar conditions by contributing to health research. Other benefits may include:

  • modifying your lifestyle for the better
  • obtaining medical care
  • taking an active role in your own health care
  • gaining access to new treatments that are not available to the general public

What are the risks of participating in a clinical research study?
There is very little risk associated with participating in an observational clinical research study but there are some risks associated with participating in a clinical trial. Risks may include:

  • side effects or adverse reactions to medications or treatments
  • the treatment may not be effective for you
  • your time and extra trips to the study site

What is an informed consent?
Informed consent is the process of learning the key facts about a clinical research study before you decide whether or not to participate. The facts include: why the research is being done, what the researchers want to accomplish, what will be done during the study and for how long, what risks are involved in the trial, what benefits can be expected from the study, and what other treatments are available. A written consent form will also tell you your rights as a research subjects, i.e. that you have the right to leave a study at any time. It will also describe how your privacy will be protected during the study. You will receive an informed consent document, given an opportunity to read it and ask any questions, and then asked to sign it. A copy of the form will then be given to you.

What protections are there for participants in a clinical research study?
The government has strict guidelines and safe guards to protect people who choose to participate in clinical research studies. All clinical studies in the US must be approved and monitored by an Institutional Review Board (IRB) to make sure risks are as low as possible and are worth any potential benefits.

Will it cost me to participate?
There will be no cost to you by participating in a NIH-sponsored clinical research study. This will be clearly outlined in the informed consent.

Can I leave a clinical study after it has begun?
Yes. You can leave a clinical research study at any time. At the beginning of a study, you will be given information on whom to contact if you decide to withdraw. You should let the research team know why you are leaving a study.

Should you volunteer for clinical research studies?
Clinical studies are vital for determining what causes human disease and for finding new cures and treatments. They are also necessary for developing new diagnostic and screening tests for a condition or identifying people who are at a higher risk. By volunteering for a clinical study, you are participating in research that may result in a new treatment for a deadly or debilitating disease. You may be helping scientists prevent future generations from developing the disease.

What types of diseases does the NIEHS study?
The NIEHS focuses on environmental diseases. These are conditions that occur due to a complex interplay between genetic susceptibility and environmental factors. Almost all common diseases are environmental including cancer, heart disease, diabetes, neural tube defects, asthma, and Alzheimers. These conditions develop because people have certain genes that predispose them towards the condition and are also exposed to certain environmental factors that trigger the condition. NIEHS researchers conduct many different types of clinical research studies to identify the genes that cause disease and investigate how our environment (toxic exposures, tobacco, lifestyle choices, exercise habits, diet, and weight control are just a few) interact with these genes. NIEHS researchers then use this information to develop new treatments and preventative strategies, and test their effectiveness in clinical trials.

Where can I find out more about clinical research and studies for specific conditions?
Here are some links that will provide you with some general information about clinical research studies, and studies for certain conditions:

Understanding Clinical Trials ( Exit NIEHS Website
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).

Search the Studies at NIH ( Exit NIEHS Website
Database of all clinical studies being conducted at the NIH Clinical Center, Bethesda, MD. Search by diagnosis, sign, symptom, or key words or phrases. ( Exit NIEHS Website
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 eyword. Hosted by NIH and the NLM. ( Exit NIEHS Website
Search the National Cancer Institute's database of more than 1,800 active cancer clinical trials. You can perform a broad search, for example, "breast cancer," or you can narrow your search by specifying other criteria such as type of trial and location. Hosted by the National Cancer Institute.

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Last Reviewed: October 30, 2008