Clinical research and clinical trials facts
- "Clinical" as a term refers to the medical care of real patients.
- Clinical trials are a form of medical research that follow a defined protocol that has been carefully developed to answer a specific patient care question.
- Clinical trials are in use to test cancer therapies, treatments for cardiovascular disease, the safety and efficacy of new drugs, and a number of other conditions.
- Clinical trials may investigate the effectiveness of new drug treatments, new combinations of drugs, surgical procedures, or behavioral and lifestyle modifications.
- Clinical trials are broken down into phases, with each phase having a different purpose within the trial.
- An Institutional Review Board (IRB) consisting of physicians, statisticians, researchers, patient advocates, and others must preapprove every clinical trial in the U.S. This ensures that the trial is ethical and protects patients' rights, and is appropriate to answer the question asked from a scientific and statistical viewpoint.
- Every clinical trial follows a protocol that describes what types of people may participate in the trial; outlines the exact schedule of tests, procedures, medications, and/or dosages involved in the trial; and specifies the length of the study.
- Each trial has specific inclusion and exclusion criteria to determine the exact patient populations that may participate. Inclusion criteria may be based on age, gender, underlying disease, health history, or other factors.
- Double-blinded trials offer the advantage of allowing the treating health-care team and the patient to make unbiased observations about patient progress and the effectiveness of the treatment being evaluated.
- Clinical trials may be sponsored and funded by government agencies, institutions, hospitals, physicians, pharmaceutical or biotechnology companies, advocacy groups, or other organizations.
- 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?
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. Clinical research studies are planned in advance and follow a defined protocol. Epidemiologic studies examine specific populations to clarify how often a disease occurs or is found in a given group (the incidence and prevalence), 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 begin and progress. 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. In cancer treatment, virtually all advances in the care of cancer patients has occurred as a result of clinical research.
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.
What are the phases of a clinical trial?
Clinical trials are broken down into phases, with each phase having a different purpose within the trial. Phase I trials involve a small group of people (20-80) and are concerned with determining a safe dose of the drug being studied as well as its potential side effects. In Phase II, the treatment or drug is tested in more people (100-300) for further evaluation - this time, determining the time of the drug or treatment's effectiveness against the disease for which the patient is being treated. Even more people (1,000-3,000) are participants in Phase III of a trial, when the intervention is compared to standard treatments and further information is collected about safety and side effects. In Phase IV trials, conducted after a treatment has been approved for specific indicated conditions by the FDA, post-marketing studies are carried out to collect more information about the optimal use of the drug or treatment and to further evaluate its side effects.
Clinical trials may be carried out in different locations, including hospitals, clinics, individual physician practices, university health centers, or community health centers.
How can one find out what clinical trials are currently being conducted?
The web site http://clinicaltrials.gov is a searchable database of federally and privately funded clinical trials being conducted in the U.S. and around the world. Your doctor or health-care team may also offer information about clinical trials that are currently under way for your specific condition.
How is a clinical trial performed, and what sort of preparation is needed?
Before a clinical trial can be carried out, thorough preparation is necessary, including extensive reviews of the proposed trial, its methodology, and the goals of the trial. An Institutional Review Board (IRB) consisting of physicians, statisticians, researchers, patient advocates, and others must pre-approve every clinical trial in the U.S. The job of the IRB is to ensure that the trial is ethical, legal, and that the rights of those participating are fully protected. For example, individual participants' names are kept secret and not included in the results or publicly available information about a trial.
Every clinical trial has a strictly defined protocol that is approved by the IRB. A protocol describes what types of people may participate in the trial; outlines the exact the schedule of tests, procedures, medications, and/or dosages involved in the trial; and specifies the length of the study. Generally, doctors check the patient thoroughly at the start of the trial, provide instructions and directions for participation in the trial, monitor the patient during the actual trial, and remain in contact, sometimes with further monitoring after the trial is completed.
In many clinical trials, patients will be randomly assigned to a test group or a control group. The control group receives the standard and accepted treatment for a given condition, while the test group receives the experimental medication or treatment to be evaluated. When a trial is "double-blinded," neither the participants nor the treating doctors know if an individual patient is receiving the standard treatment versus the experimental treatment. Double-blinded trials offer the advantage of allowing the treating health-care team and the patient to make unbiased observations about patient progress and the effectiveness of the treatment being evaluated. A double-blind study is also referred to as a double-masked study. Results obtained from a randomized, double blind clinical trial are considered the most accurate and reliable types of results, and help those conducting the trial to draw the most accurate conclusions.
What is informed consent?
Informed consent is giving your consent to participate in the clinical trial after having learned about the trial and having had the opportunity to ask questions. You should be fully aware of all the details, risks vs. benefits, and expectations of the trial before agreeing to participate. When you give informed consent, you sign a document - which should be in a language that you understand - that describes the rights of the participants as well as gives details of the study and names of the investigators who are conducting the study and contact information for these people.
Is patient privacy maintained in a clinical trial?
Clinical trials are required to maintain strict patient privacy. Your name will not be published anywhere that data about the trial are published or included in any publicly available information. Some clinical trials may require that you be seen and examined by a larger treatment team than would typical medical care. For example, this may include research nurses who only see patients enrolled on clinical trials.
Who can participate in a clinical trial?
Each trial has specific inclusion and exclusion criteria to determine the exact patient populations that may participate. Individuals who fit the predefined and preapproved inclusion criteria for a trial may participate if the trial is currently accepting participants. Inclusion criteria are based on factors such as patient age, gender, the type and stage of a disease, previous treatment history, and other medical conditions. Some clinical trials seek participants with illnesses or conditions to be studied in the clinical trial, while others need healthy participants.
Are people paid for participating in clinical trials?
Some clinical trials offer monetary compensation for participants. Other trials may offer their participants free health care that is related to the condition being studied, or screening examinations. There are no requirements for those who sponsor clinical trials to pay or otherwise compensate participants.
What are the pros and cons of participating in a clinical trial?
The benefits of clinical trials are many and range from taking an active role in the management of one's own health care, helping others by aiding the process of knowledge acquisition and development of enhanced treatments, being cared for by - or in accordance with the protocol which has been developed by - leading health care teams in a given field, and in some cases, receiving access to new treatments before they are approved. However, there are also risks, including side effects of drugs and risks of any procedures that may be performed. In some cases, clinical-trial participation may require more frequent doctor visits or hospitalizations than standard care, and you may have to travel to a study site that is farther away than your local health-care practitioner's office.
Some questions you may want to ask before participating in a clinical trial include the following:
- What is the purpose of the trial?
- Is a new type of treatment being tested? How does this differ from the accepted or standard therapy for my condition?
- Has the drug or treatment ever been tested before?
- How will participation impact my daily life and schedule? Will it be necessary to be in the hospital?
- What are the risks and possible side effects of the treatment?
- Who will pay for the treatments? Will I receive reimbursement or any type of compensation for my time or expenses?
- How long is the trial expected to last?
- How will I receive results of the trial, and how will I know if the treatment is successful?
Can a person leave a clinical trial once it has started?
An informed consent document is not a legal contract that requires participation in a study for the length of a study. A participant is free to leave a clinical trial at any time without prejudice to their ongoing medical care. They will not have access to the experimental medicine being studied if they leave the trial.
Who sponsors clinical trials?
Clinical trials can be sponsored or funded by a variety of organizations or individuals. Federal agencies such as the National Institutes of Health (NIH), the Department of Defense (DOD), and the Department of Veteran's Affairs (VA) frequently fund and sponsor clinical trials. Additionally, clinical trials may be sponsored by medical institutions, charitable foundations, advocacy groups, physicians, and/or biotechnology or pharmaceutical companies.
What happens after a clinical trial is completed? Is there follow-up care?
The researchers in the trial will stay in contact with participants and inform them of the conclusions of the trial. In some cases, you may be asked to provide long-term follow-up in the form of patient surveys or periodic health examinations. Since most clinical trials provide short-term treatments related to a specific condition, they are not a substitute for primary health care. Your regular health-care provider should be aware of the trial and will work with the researchers during the trial. When the trial is over, you will continue to receive care through your primary care provider and any other practitioners required for your condition.
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