Once researchers have tested new molecules, treatments, products, or procedures in the laboratory and then on animals, the most promising ones move on to clinical trials. Why do clinical trials? What is the importance of these investigations? If you want to discover the answer to these questions, stay with us until the end of this post.

Why do Clinical Trials ?


What is a clinical trial?

A clinical trial is a scientific investigation aiming to better understand the actions, effects, and other properties of a medicine, vaccine, diagnostic technique, or therapeutic, diagnostic, etiology, and prognostic procedures, to verify if it is effective and safe in humans and compare its action with that used up to that moment in clinical practice. For this reason, it is a necessary procedure in medical and pharmaceutical research through which all treatments must pass before being marketed and used in patients.


What are clinical trials done for?

According to their purpose, methods, extension, or size, there are five types of clinical trials. Discover below what they are and what each one of them is made for:

  1. Diagnostic Clinical Trials: Designed to find new diagnostic medical tests. It determines the degree to which the treatment is feasible and clinically practical in order to determine if the patient will benefit from it.
  2. Treatment clinical trials: Evaluate new therapeutic procedures to cure a disease. It determines which treatment to give and the outcome of different treatment options.
  3. Screening clinical trials: Evaluate new methods to diagnose a disease early. Sometimes, it identifies the relationship between a disease and a possible cause.
  4. Preventive clinical trials: study new tools for diseases. They answer questions about the patient’s future health, life expectancy, and quality of life.
  5. Quality of life trials: their objective is to design strategies that improve the quality of life of people with chronic diseases.


What are the phases of clinical trials?

These clinical trials go through several phases, and each of them has a different objective:

  1. Phase I: It checks whether the treatment is safe and what is the best way to administer it. In general, the study is conducted with a small number of participants.
  2. Phase II: In this stage, the effectiveness of the treatment is analyzed with a broader group of participants.
  3. Phase III: Safety and efficacy aspects of the drug are verified and, if possible, compared with other treatments used. The number of participants is much larger. After this phase and according to the results, drug regulatory agencies can grant authorization and marketing of the drug under specific indications.
  4. Phase IV or Follow-up Studies: These examine the long-term effects of the treatment once it is on the market.


What is the importance of clinical trials?

Due to their objectives and characteristics, clinical trials are procedures of great importance for the development of science, medicine, and, ultimately, humanity’s well-being.

  • They are the last step in scientific research: clinical trials allow to validate the results obtained during preclinical research.
  • They can specify the best way to apply the treatment, the appropriate dose as well as the possible adverse effects that patients may experience.
  • They can transform the evaluated treatment into a new standard of medical practice. Once the safety and efficacy of therapy have been demonstrated in a clinical trial, it becomes a reference in its area.
  • They make treatment registration and approval possible: In some countries, such as the United States, the authorities require that researchers test the new products and treatments used in the country in clinical trials to guarantee their effectiveness and safety.


What are the benefits and drawbacks of doing clinical trials?

Clinical trials have a group of benefits and drawbacks that people must consider.


  • Your results are accurate
  • They allow demonstrating the validity of new treatments for diseases or treatments for diseases that had no cure
  • They constitute a contribution to science and medicine


  • They are expensive
  • In most cases, they require a lot of time to develop
  • There is always the risk that the results will differ from what is expected


Why do clinical studies?

After having analyzed the objectives, importance, benefits, and drawbacks of clinical trials, we can answer why to do this type of research:

  • They are a safe way to validate new treatments or procedures for diagnosing, preventing, and solving diseases.
  • Ensure that new treatments are safe and effective.
  • They allow to identify the best way to apply a treatment (dose/form of administration/duration of treatment)
  • Its results are necessary for the marketing authorization and use of new products or treatments.
  • They favor the development of science and research applied to people’s health.

For the reasons mentioned above, there is no doubt that conducting clinical studies is a prevailing need to guarantee better health for all people. With them, finding viable solutions to humanity’s health problems would be easier.


Frequent questions

What do clinical trials pay?

Although not all clinical trials pay their participants, a good part of them does so as compensation for the time the subjects have to dedicate to these processes and the risk they may run. As simple as it may be, participating in a clinical trial can require time and related travel and expenses. Well, yes, those who participate in the trials will usually have to make numerous visits to the doctor and use apps or phone calls for regular monitoring, and all this comes with expenses. The total value of the payment is generally determined by the number of visits to the research center where the trial is carried out, the time of the examinations related to the study, the phase of the study, and the type of research carried out.

What is an example of a clinical trial?

An excellent example of a clinical trial is those that were carried out after the start of the pandemic caused by COVID-19. Given the need to discover effective vaccines to control the epidemiological situation in the country, companies such as Pfizer and Moderna conducted clinical trials to validate their vaccine candidates. Due to the results obtained, the United States Food and Drug Administration (FDA) approved these drugs, which were applied to millions of people, which has helped reduce the incidence of this disease.

Who cannot participate in clinical trials?

Each clinical trial establishes specific eligibility criteria that must be met by people who are interested in participating in the study. Likewise, if necessary and for safety reasons, exclusion criteria are also established, and those volunteers who meet them cannot access the study. These criteria are informed before starting the research and are generally published together with the calls for trials.

What are the risks of clinical trials?

Those who participate in clinical trials should be aware that they will be exposed to certain risks:

  1. Side effects from using the new treatment
  2. The possibility of receiving a placebo, so you will not benefit from the new treatment. However, patients receiving a placebo are often given the treatment after the end of a trial.
  3. The treatment may not be effective for you.

There are also specific risks according to each trial. For this reason, it is important that you request all the information on this subject before deciding whether or not to participate in the study.

However, all these risks are mitigated from the very conception of the study design and later during the follow-up of the evolution of the participants.


Who are clinical trials run by?

Clinical trials are designed by experts in the diagnosis and treatment of patients with a particular disease. They are usually carried out by research centers, hospitals, universities, the National Institutes of Health (NIH), and other specialized institutions. In addition, they are submitted for the evaluation and approval of the health authorities. For example, in the case of the United States, before a clinical trial of a new medicine can start, it must receive authorization from the Medicines and Healthcare products Regulatory Agency (MHRA). Each country has an authority of this type.

What is the difference between a clinical trial and a clinical study?

A clinical trial is a component of a clinical study. A clinical study or clinical research is a process by which experts investigate different conditions and treatments. There are two main types of clinical studies: observational and studies clinical trials. 

How to participate in a clinical trial?

In the United States, most ongoing clinical trials appear in ClinicalTrials.gov, a database administered by the US National Library of Medicine. In the database appear all the information about the clinical studies carried out in the country and worldwide financed with public and private funds.

Some websites help match people to specific trials. Such is the case of the National Institutes of Health (NIH), which have an Internet-based registry called Research Match. People can use this resource to connect with researchers looking for trial participants. CenterWatch is an additional service that lists thousands of trials currently recruiting people.

In addition, it is possible to find clinical trials available through the Internet, the press, and radio. Generally, centers dedicated to clinical trials use these media to launch clinical trial recruitment notices. Furthermore, you can receive a direct invitation or suggestion from your doctor.

In this way, we come to the end of this post dedicated to discovering why clinical trials. We hope that you found them interesting and that you can clearly understand the importance of studies of this type. Undoubtedly, this is a fascinating topic. If you want to know more about it, we invite you to consult all the articles our team has prepared on clinical trials and their characteristics.


Having a successful clinical research site is one of the most rewarding businesses out there.  You are at the forefront of the pharmaceutical industry’s development of potentially life saving treatments.  When a trial participant benefits from a breakthrough medication you are responsible in part for that.  The keys to a successful site have been laid out above. With good management and building a long-lasting relationship of trust with your patients and in your community, your site will ensure long term financial success.