What are the different types of clinical research?

Different types of clinical research are used depending on what the researchers are studying. Below are descriptions of some different kinds of clinical research.

Treatment

Treatment research (also called “clinical trials”) generally involves an intervention such as medication, psychotherapy, new devices, or new approaches to surgery or radiation therapy.

Prevention

Prevention research looks for better ways to prevent disorders from developing or returning. Different kinds of prevention research may study medicines, vitamins, vaccines, minerals, or lifestyle changes.

Diagnostic

This refers to the practice of looking for better ways to identify a particular disorder or condition.

Screening

Screening research aims to find the best ways to detect certain disorders or health conditions.

Quality of life

Also known as “supportive care,” this research explores ways to improve comfort and the quality of life for individuals with a chronic illness.

Genetic studies

Genetic studies aim to improve the prediction of disorders by identifying and understanding how genes and illnesses may be related. Research in this area may explore ways in which a person’s genes make him or her more or less likely to develop a disorder. This may lead to development of tailor-made treatments based on a patient’s genetic make-up.

Epidemiological studies

Epidemiological studies seek to identify the patterns, causes, and control of disorders in groups of people.

An important note: some clinical research is “outpatient,” meaning that participants do not stay overnight at the hospital. Some is “inpatient,” meaning that participants will need to stay for at least one night in the hospital or research center. Be sure to ask the researchers what their study requires.

Phases of clinical trials: when clinical research is used to evaluate medications and devices

Clinical trials are a kind of clinical research designed to evaluate and test new interventions such as psychotherapy or medications. Clinical trials are often conducted in four phases. The trials at each phase have a different purpose and help scientists answer different questions.

Phase I trials

Researchers test an experimental drug or treatment in a small group of people for the first time. The researchers evaluate the treatment’s safety, determine a safe dosage range, and identify side effects.

Phase II trials

The experimental drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.

Phase III trials

The experimental study drug or treatment is given to large groups of people. Researchers confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the experimental drug or treatment to be used safely.

Phase IV trials

Post-marketing studies, which are conducted after a treatment is approved for use by the FDA, provide additional information including the treatment or drug’s risks, benefits, and best use.

Examples of other kinds of clinical research

Many people believe that all clinical research involves testing of new medications or devices. This is not true, however. Some studies do not involve testing medications and a person’s regular medications may not need to be changed. Healthy volunteers are also needed so that researchers can compare their results to results of people with the illness being studied. Some examples of other kinds of research include the following:

• A long-term study that involves psychological tests or brain scans
• A genetic study that involves blood tests but no changes in medication
• A study of family history that involves talking to family members to learn about people’s medical needs and history.

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