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Research Studies and You

A clinical study involves research using human volunteers (also called participants) that is intended to add to medical knowledge. There are two main types of clinical studies: clinical trials and observational studies.

Interventional Studies and Observational Studies

Interventional studies are also known as clinical trials. Participants in this type of study receive specific interventions according to the research plan or protocol created by the investigators. These interventions may be medical products, such as drugs or devices; procedures; or changes to participants' behavior, for example, diet. Clinical trials may compare a new medical approach to a standard one that is already available or to a placebo that contains no active ingredients or to no intervention. Some clinical trials compare interventions that are already available to each other.

In observational studies, investigators assess health outcomes in groups of patients. They also follow a protocol or research plan. Participants may receive interventions, which can include medical products, such as drugs or devices, or procedures as part of their routine medical care. Participants are not assigned to specific interventions by the investigator (as in a clinical trial). For example, investigators may observe a group of older adults to learn more about the impact of bone marrow failure diseases on their quality of life.

What are the different types of clinical trials?

There are many types of clinical trials.

  • Treatment trials test new treatment options. For example, treatment trials for bone marrow failure may study a new medicine. Or, the study may look to find a new use for one or more drugs that are already being used. Treatment trials make sure a treatment is safe and effective before it is approved for wider use.
  • Diagnostic trials test and evaluate new ways to diagnose a disease.
  • Screening trials test the best way to detect a disease or health problem.
  • Quality of life trials are also called supportive care trials. They study ways to improve the comfort and life quality of people with a long-term illness.
  • Prevention trials look for better ways to prevent disease in people who have never had the disease. They may also explore ways to stop a disease from coming back. These trials may include using medicines, vaccines, or vitamins, or making changes in lifestyle.

What are the phases of clinical trials?

Clinical trials are carried out in phases, each designed to find out certain information. These phases are defined by the Food and Drug Administration (FDA). A new drug treatment must first be tested in a lab or in animals before it is tested in people. Then, before a drug can become part of standard treatment, it must first go through 3 or 4 clinical trial phases. Each phase has a different purpose and helps scientists answer different questions.

  • Phase I – Is the drug safe? These studies are often conducted with healthy volunteers. Safety is important in these studies.
  • Phase II – Does the drug treatment work? Does the new drug have a positive effect on people with a certain disease or condition?
  • Phase III – Is the new drug treatment better than the standard treatment? These studies look at the safety and effectiveness of a new treatment compared to the standard treatment for a disease or condition.
  • Phase IV – What is the long-term impact of the new drug treatment? How safe and effective is the new drug or treatment once it has been approved to enter the market by the Food and Drug Administration (FDA)?

You do not have to take part in all the phases. The early phases of a research study make sure the drug or treatment is safe. The later phases of the study show if it works better than the treatment used now.

Phases of Clinical Trials

Number of People Who Take Part in Each Phase

Phase I – Is the drug safe? These studies that are often conducted with healthy volunteers . Safety is important in these studies.
  • To find a safe dosage range
  • To decide how the new treatment should be given and how a drug or treatment is used by the body
  • To see how the new treatment affects people and what the side effects are
  • Note: If the medicine or treatment is found to be safe, the study moves on to Phase II
Often 20 – 80
Phase II – Does the drug treatment work?
  • To find out if the new drug treatment has a positive effect on people with a certain disease or condition
  • To continue to assess the safety of the drug
  • To gather more information about how the new treatment affects people
Note: It is usually in Phase II trials when the researchers find out if the drug is not working as planned or has toxic effects.
Often 100 - 300

Phase III – Is the new drug treatment better than the standard treatment?
  • To compare the safety and effectiveness of the new treatment with the standard treatment
  • To compare how the treatment works in different populations, or with what treatments.
  • To continue to watch for side effects and collect information that will allow the treatment to be used safely
Note: Some Phase III trials use a method called "randomization." This means people in the study are placed in different treatment groups by chance or at random. One group may get the new treatment, one group may get the standard treatment, and one group may not get any treatment.
Often 1,000 - 3,000
Phase IV – What is the long-term impact of the new drug treatment?
  • To look at how safe and effective the new drug or treatment is over the long term once the drug has been approved to enter the market by the Food and Drug Administration (FDA)
Often several hundred to several thousand


Who sponsors or provides funds for clinical trials?

They can be sponsored or funded by:

  • Medical or health institutions
  • Foundations
  • Pharmaceutical companies
  • Voluntary groups
  • Federal agencies, such as the National Institutes of Health, or NIH for short

How is my safety protected if I join a clinical trial?

In the United States, there are strict guidelines to make sure that people who agree to be in a clinical trial are treated as safely as possible. These guidelines apply to all medical research involving human participants. The guidelines require the following:

  1. An institutional review board, also called an IRB, must review and approve every clinical trial plan. Every place doing a clinical trial must have an IRB. This review helps make sure that the risks of the study are small and are worth the possible benefits.
  2. Informed consent must be given by a patient before being in the study. Informed consent can be confusing. It means that you agree (consent) to be in the study and you understand all the facts about the being in the study, including any possible harm it may cause you.

What is an Institution Review Board (IRB)?

An institutional review board, also called an IRB, is a committee that makes sure a clinical trial is safe for patients in the study. Each medical center, hospital, or research facility doing clinical trials must have an active IRB.

Each IRB includes a diverse group doctors, faculty, staff and students at a specific institution. An IRB must also have at least one person from the community who is not connected to the institution. This board goes over each study plan and makes sure that the highest standards are met to protect the rights of the study participants.

What is Informed Consent?

Informed consent is a process in which researchers provide potential and enrolled participants with information about a clinical study. This information helps people decide whether they want to enroll, or continue to participate, in the study. The informed consent process is intended to protect participants and should provide enough information for a person to understand the risks of, potential benefits of, and alternatives to the study. Informed consent for a clinical trial is much more than just reading and signing a piece of paper. It involves two essential parts:

  • An informed consent document
  • A process that includes many conversations with the medical team doing the clinical trial

The informed consent document reviews all the information about the clinical trial. This document includes:

  • The purposes of the research study
  • How long the study will last
  • The tests and treatments you will get
  • The possible risks
  • The potential benefits of being in the study
  • Your rights as a participant. For example, you have the right to leave the study at any time

If there is even a small risk of your getting injured by being part of the research study, the informed consent document must also include:

  • Who to contact if you are injured by being in the study
  • A list of health treatments to treat an injury and how to get more information about these treatments
  • Whether or not you are able to get any money (compensation) if you are injured and how this money can be obtained

Reading the informed consent document begins the informed consent process. This process includes a series of conversations between you and the research team. During these conversations the study researchers may also explain:

  • Other treatments, if any, that you might use instead of the treatment being used in the study (This allows you to know all your treatment options before joining the research study.)
  • How your records identifying you will be kept private
  • Who can answer your questions about the research

Informed consent continues after you are in a clinical trial. It includes ongoing talks with the doctors and nurses doing the clinical trial. These conversations will help you make good decisions about whether to stay in the trial. Before, during, and even after the trial, you can ask questions and raise concerns. So informed consent is an ongoing and interactive process. It is not just a one-time information session or a form you read and sign.

How do I decide whether or not to participate?

You will want to look at all the pros and cons of any research study before choosing to be part of the study. Take the time to talk about the risks and benefits with others. Talk to your doctors and family to decide if being in the study is right for you.

Kristin Dodd, RN, a member of the AA&MDSIF Nursing Network from the Cleveland Clinic Foundation shared some reasons for patients to consider becoming involved in clinical trials. First, patients in a clinical trial are likely to be monitored more closely.  There is an increase in lab draws and tests such as EKGs, CT scans or MRIs as well as an increased number of clinic visits with the doctor and nurse, compared to the standard of care visits when not involved in a clinical trial. Because of this more intense schedule and level of monitoring, clinical trial participants often indicate they feel more secure. 

During a clinical trial, participants receive the study drug at no cost to them.  All of the study-related services are often covered in full by the sponsor conducting the clinical trial.  Participants may even be able to recoup out-of-pocket expenses, such as parking, travel, and food or hotel costs.  Some patients experience a sense of relief when these burdens of cost are lifted from their shoulders. Contrary to what many think, standard-of-care aspects of a clinical trial are still covered by a patient’s health insurance.

When a patient participates in a clinical trial, other available FDA-approved therapies are still available later on, in case a trial medication doesn’t work.  Some trials may exclude patients previously treated with currently available drugs.  In this case, if a patient participates in a clinical trial that does prove effective, he or she can then move on to another clinical trial or pursue FDA-approved treatment. 

In conclusion, having the opportunity to participate in clinical trials enables you to make informed decisions about your health. You may get access to experimental drugs that may not become widely available for years, and if the trial drug does not work, there are other trials out there.  If clinical trials are not a good fit for you, then you can turn to FDA-approved therapies.  To find out where to look for clinical trials in your area contact our patient educator, ask your doctor, contact any major medical center in your area, or visit

Take this information with you when you talk with the research team. Use the questions below as you decide.

Questions to ask about a clinical trial

About the study:

  • What is the purpose and phase of this study?
  • Who is going to be in this study?
  • Why do researchers believe the new treatment being tested may be effective? Has it been tested before, and if so, what were the findings?
  • Who is sponsoring this study?
  • Who has reviewed and approved the study?
  • How long will the study last?
  • Who will be in charge of my care during the study?
  • Will I have to travel to be part of this study? If so, who will pay for travel?

About tests or treatments in the study:

  • What kinds of tests and treatments are involved?
  • What tests will I get as part of this study?
  • Will I have to pay for any treatment or test?
  • How do the possible drawbacks and benefits compare with those of my current treatment?
  • What are the known short-term and long-term side effects of the treatment?
  • How might being in this study affect my daily life?
  • Will I need to go into the hospital to get the treatment or drug? If so, how often and for how long?
  • How will I know that the treatment is working? Will results of the study be shared with me?
  • If the treatment being studied is found to be harmful or not working, will I stop taking it?

After the study is over:

  • Will I be able to still get this treatment after the study ends?
  • What type of long-term follow-up care is part of this study?

Myths vs Facts

The Seattle Cancer Care Alliance has an article discussing some of the Myths vs. Facts About Clinical Trials.