Learn What Clinical Trial Studies Are

Clinical research is medical research that involves humans. There are two kinds of research: observational studies and clinical trials.

  • Observational studies look at people in their natural surroundings. Researchers collect data, categorize participants based on broad traits, then compare changes across time. For example, researchers may collect data on a group of older persons over time using medical exams, tests, or questionnaires to learn more about the effects of varied lifestyles on cognitive health. This research may aid in the identification of new clinical trial sites.
  • Clinical trials are human research studies that evaluate a medicinal, surgical, or behavioral intervention. They are the primary means by which researchers determine whether a novel treatment, such as a new medicine, diet, or medical equipment (such as a pacemaker), is safe and effective in humans. A clinical trial is frequently performed to determine whether a novel treatment is more successful and has fewer harmful side effects than the current treatment.

Other clinical studies look for techniques to detect an illness early, sometimes before symptoms appear. Others are experimenting with techniques to avoid a health problem. A clinical trial may also investigate how to improve people’s lives who have a life-threatening condition or a chronic health problem. Clinical studies may also investigate the role of carers or support groups.

Before the U.S. Food and Drug Administration (FDA) allows a clinical trial, scientists conduct laboratory tests and animal studies to assess the safety and efficacy of a prospective medication. If these studies yield positive results, the FDA grants permission to study the intervention in humans.

What are the four clinical trial phases?

Clinical trials go through four stages to evaluate a medication, determine the proper dosage, and examine negative effects. If researchers find medicine or other intervention safe and effective after the first three phases, the FDA approves it for clinical use and continues to evaluate its effects.

Drug clinical trials are typically defined in terms of their phases. For example, to assess if a medicine can be approved for use, the FDA normally requires Phase I, II, and III trials to be undertaken.


A Phase I study evaluates an experimental treatment on a small sample of often healthy people (20 to 80) to determine its safety and adverse effects, as well as the appropriate drug dosage.

More participants are used in a Phase II trial (100 to 300). While Phase I is focused on safety, Phase II is focused on effectiveness. This Phase seeks preliminary evidence on whether the medicine works in persons with a specific disease or condition. These trials are also studying safety, including short-term negative effects. This stage can endure for many years.

A Phase III trial collects further information regarding the medicine’s safety and effectiveness by evaluating different populations and dosages and utilizing the drug in conjunction with other medications. The number of subjects typically ranges from a few hundred to around 3,000. If the FDA agrees that the trial results are positive, the experimental medication or gadget will be approved.

After the FDA has approved the use of a medicine or device, it is subjected to a Phase IV trial. The effectiveness and safety of a gadget or medicine are evaluated in broad, diverse groups. It is not uncommon for the adverse effects of a drug to become apparent only after many people have used it for an extended length of time.

Why should you take part in a clinical trial?

People opt to participate in clinical trials for a variety of reasons. Some people join a clinical study because the treatments they’ve tried for their health problems haven’t worked. Others engage since there is no cure for their medical condition. Participants in clinical trials may learn about novel medicines before they are generally available. Finally, some studies are intended for or include healthy people but want to contribute to discovering strategies to prevent disease, such as one that runs in their family.

Many people believe that taking part in a clinical trial allows them to take a more active role in their health treatment. Others say they want to help researchers understand more about specific health issues. However, when you choose to enroll in a clinical trial, you become a collaborator in scientific discovery, regardless of your motivation. Furthermore, your gift has the potential to assist future generations in enjoying healthier lives. Major medical advances would not be possible without the generosity of clinical trial participants, whether young or old.