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What is clinical research?

Clinical research studies are the final step in evaluating new drugs, devices or procedures to establish their effectiveness and determine any risks associated with their use. It can also involve comparing healthy volunteers to individuals with specific conditions in order to learn more about what causes disease and why some people are more likely than others to experience depressive illnesses.

Clinical research is a partnership between healthcare professionals, scientists, and patients with the goal of improving medical care, curing diseases, and improving quality of life.

There are 4 different types of clinical research studies:

  • Intervention studies are used to assess the effectiveness of new drugs, devices, or procedures.
  • Prevention studies attempt to find better strategies to prevent disease. Medicines, vitamins, vaccines, and lifestyle changes are all examples of prevention strategies that could be tested.
  • Diagnostic or screening studies are conducted to improve the tests or procedures used to detect the presence of a disease or condition.
  • Quality of life (also called supportive care) studies look for ways to help people with chronic illnesses live fuller, more comfortable lives.

Clinical research studies are also categorized into 4 phases, based on the purpose of the study:

  • Phase I studies are the first opportunities to test drugs, devices or procedures with humans. Conducted with a relatively small group of people (20-80), the purpose of Phase I studies are usually limited to determining whether a drug or device is safe.
  • Phase II studies involve a larger pool of people (100-300), and are conducted to evaluate effectiveness (and to further study safety issues).
  • Phase III studies are very large-scale trials (1,000 – 3,000 people), that are used to confirm the effectiveness of a drug, device or procedure, and to understand any side effects. Successful completion of a Phase III study may open the door to approval to make the treatment available to the general public (although ongoing testing may still be required).
  • Phase IV research collects additional information about the risks, benefits and optimal usage of the treatment.

Who participates in research?

Thousands of people take part in research studies each year to test new ways to prevent, detect, or treat diseases. Research studies are conducted with every group of people- from infants to the elderly, men and women of all racial and ethnic backgrounds, and both healthy volunteers and those with serious medical conditions.

Since medications and other treatments may work differently with different groups of people, it is important that clinical studies measure outcomes for diverse populations, so that the solutions developed will work well for all groups.  

Each study has specific guidelines about who can participate so that researchers can accurately evaluate how well the treatment they are studying works. If one study isn’t a good fit for you, there are probably many others that need your help!

Is clinical research safe?

The safety of participants is the top priority in clinical research studies. Before any clinical study can begin recruiting volunteers, the design of the study (called the protocol) must be approved by a group called the Institutional Review Board (IRB), which is an independent team of doctors, experts in medical ethics, and community members. In addition, the federal government regulates most clinical research.

What is informed consent?

The “informed consent process” is how a person learns the facts about a research study before deciding whether to participate. The healthcare professionals involved in the study explain all of the details, and provide a document that summarizes the study’s purpose, length, required procedures, known risks and benefits, and key contact people. The informed consent document is not a contract— it simply ensures that all of the relevant study information has been explained. Even after you sign an informed consent document, you may still leave the study at any time.

Should I participate in a research study?

Potential advantages:

  • Provide you with new information about your condition.
  • Access and possibly benefit from new treatments before they are widely available.
  • Receive additional medical care and attention from doctors and other health professionals at a reduced cost or no cost.
  • The chance to help others by increasing knowledge.

Potential disadvantages:

  • Testing a drug that does not work, or does not work as well as anticipated.
  • Unpleasant or serious side effects of the treatment.
  • The time, energy, and resources involved in meeting all the requirements for participation in a study.
  • Costs associated with medications or procedures, which may or may not be covered by insurance.
  • There is no guarantee that you will learn the final results of the research study you participate in.
  • The possibility that, for any number of reasons, you may be removed from the study at any time.

Learn more about joining a study from several Eisenberg Family Depression Center researchers who have provided their perspectives on participation based on their many years of experience developing studies and working with participants.

If you are considering participating in a clinical research study:

  • Discuss your options in detail with your healthcare provider and with a qualified individual who can address issues related to the specific study or studies that interest you.
  • Read a blog post from a research participant with the Prechter Bipolar Research Program: Why I Participate.
  • Find out how you can participate in a study at the University of Michigan or somewhere else in the country.


US National Library of Medicine. (2015). For Patients and Families. Retrieved from