Before joining a clinical study, you must first qualify for the study. All clinical studies have guidelines about who can participate to ensure it is for you. The use of inclusion/exclusion criteria is an important principle of clinical research that selects the proper participants. The factors that allow you to participate in a clinical study are called “inclusion criteria” and those that disallow you from participating are called “exclusion criteria.”

These criteria are based on such factors as age, the type and stage of disease, previous treatment history, and other medical conditions. Some research studies seek subjects with illnesses or conditions to be studied, while others need healthy subjects. It’s not personal! Inclusion and exclusion criteria are not used to reject potential participants. Instead, they are used to identify the right subjects and keep them safe.

The criteria help ensure that researchers will be able to answer the questions posed in the study.


Clinical studies are designed and executed to allow eligible subjects to:

  • Play an active role in their own healthcare
  • Gain access to new research treatments before they are widely available
  • Obtain expert medical care at healthcare facilities during the study
  • Help others by contributing to medical research


There are risks to clinical studies, including:

  • Possible unpleasant, serious or even life-threatening side effects from the experimental treatment
  • Ineffectiveness: the experimental treatment may not be effective for you
  • Time spent: The study may require your time and attention, due to multiple visits to the study site, frequent treatments or hospital stays, etc.

The ethical and legal codes that govern medical practice also apply to clinical studies. In addition, most clinical research is federally regulated with built-in safeguards to protect participants.

The study follows a carefully controlled protocol—a study plan that details what researchers will do in the study. As a clinical study progresses, researchers will report any unexpected events of the study to various government agencies and ethics boards, who will in turn, decide if the study should continue or not. Individuals’ names will remain confidential and will not be mentioned in these reports.

It is important that you feel informed and comfortable about clinical trials before participating. You are encouraged to ask the members of the healthcare team questions about the study and the treatment you will receive while you’re in a study. The following questions might be helpful for you to discuss with the healthcare team.

Some of the answers to these questions are also found in the informed consent document.

Side effects are any undesired actions or effects of the experimental drug or treatment. Negative or adverse effects may include headache, nausea, skin irritation, or other physical problems. Experimental treatments must be evaluated for both immediate and long-term side effects.

Before agreeing to participate in a clinical study, you should first examine all available information on the study and, where appropriate, on the medication being tested. This information is presented in a written document, also known as the “informed consent form,” given to each person who wishes to participate in the clinical study and must be signed if you choose to participate.

This form includes information about the study, such as its purpose, duration, required procedures, and key contacts.

The risks and potential benefits are explained in the informed consent form. You can then decide whether or not to sign the document. The informed consent form is not a contract, and you may withdraw from the study at any time.

Your participation is valued and important to us so that we can collect important information on the tested product. However, you have the right to leave a clinical trial at any time, without justification and without penalty or loss of benefits assigned to you, even if you have already signed the consent form.

When withdrawing from the study, you need to inform the research team. You may be compensated for the visits you made and could be recalled later for long-term monitoring for safety purposes.

Financial compensation may be offered to clinical study participants for travelling expenses and the time allocated to their participation in the study. This amount is usually paid at the end of the clinical study when all visits are completed. This may vary from one study site to another and depending on the study duration. For long studies, interim payments may occur.

Some clinical studies are only carried out to evaluate harmlessness (safety) and tolerance of the tested product. Other clinical studies also aim to evaluate the effectiveness of the product. Some information on the effectiveness of the product being studied is found in the informed consent form.

Any clinical trial may start only once the given country regulatory body (or health authorities) has approved and authorized the study, and once the ethics committee approvals are obtained.

Government agencies tasked with clinical trial oversight have the mission to improve and maintain the health of their population. Their evaluations focus on the product, the rationale of the study and examinations to be carried out during the study.

The Ethics Committee independently reviews all the ethical aspects of the study to protect the rights and well-being of research subjects.

Any change to an on-going study must be approved by an ethics committee and, depending on the type of change, the regulatory body, before being implemented.

It is the duty of the company developing the medication, the organisation managing the study, and the study doctor, to report to the ethics committee and to the country regulatory body, any new information that may have an impact on the proper study conduct or on the safety and well-being of the subject.

Before starting a clinical trial, a form confirming the selection of the study doctor must be forwarded to Health authorities. This document states that the physician will conduct the study in accordance with Good Clinical Practice (GCP), a standard that ensures that the rights, the safety and well-being of subjects are respected. Moreover, in order to monitor and ensure compliance of GCP and compliance with legal requirements, inspections at clinical sites can be conducted at any time by a government agency, either domestic or foreign.