The clinical trial may be conducted on a randomized basis. In this situation, the patients undergoing the trial are divided into two groups. One is the control group, and the other is the group that is being treated.

The concept of a clinical trial

Before being introduced to the market, each drug or form of therapy goes through the stage of clinical trials. This type of actions aim to determine whether the preparation tested in laboratory conditions has a proper effect on people suffering from a given disease.

These types of tests are carried out by qualified persons who have undergone medical research courses and have the knowledge necessary to ensure safety to those participating in the trial. This is the basic condition set for the organizers of clinical trials – above all, trials must be safe for participants. Although the people who undergo treatment as part of the clinical trial sign documents saying that they are aware of the risks, a team of experienced specialists still supervises the well-being of the participants of the trial.

What is a control group?

For the trial to be carried out in a way that allows for an actual answer to the question of whether a given drug works, it is necessary to create two groups of patients: people who receive the drug that is the subject of a given clinical trial and a control group, that is, people who under the same conditions receive a placebo or known and proven drugs for a given disease.


Importantly, patients are assigned to groups on a random basis, and their leaders – and the subjects themselves – have no idea whether they are receiving the treatment subject to the clinical trial or just a placebo. This type of action has scientifically proven effectiveness and allows maintaining an objective and reliable assessment of all issues related to a given preparation or form of therapy.

Why are control groups created?

The control group in the clinical trial plays a vital role in the objective assessment of the product’s effectiveness. Since some respondents do not receive the tested therapy, it is possible to actually check its effectiveness and assess if it is better than the forms of therapy already available on the market. It also allows for an assessment of any slowdown in disease progression by comparing the data for both groups – both those receiving treatment and those taking a placebo.

Obtaining this kind of knowledge increases the objectivity of the trial. It is worth remembering that people who have already been refused other forms of treatment or suffer from diseases for which there is no effective therapy yet often apply to participate in clinical trials. Such patients usually treat their participation in a clinical trial as a last chance, which means they approach this type of therapy with high hopes. This, in turn, can lead to the false impression that the trial is having positive results when, in fact, the therapy is ineffective.