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Understanding the trial and informed consent

Before you decide to join a clinical trial, you need to understand the protocol. A protocol is a written description of the trial. It explains why the trial is being done, how it will be conducted and how your safety will be protected.

The protocol will also include information on:

  • who can participate in the trial (eligibility)
  • how many people will take part in the trial
  • what type of treatment will be given and how often
  • what medical tests you will have during the trial and how often
  • how long the trial is expected to last
  • how the researchers will know if a treatment is working
  • what type of information will be collected and how the information will be analyzed

Where clinical trials are held

A clinical trial usually takes place in the same location where standard cancer treatment is given – cancer centres, hospitals, clinics or doctors’ offices. While some trials enrol people at 1 or 2 locations only, a large clinical trial may involve thousands of people at hundreds of locations across the country or around the world.

If you live in a small town or rural area, you may need to travel to a larger city to participate in the trial and take follow-up tests.

The clinical trial team

Clinical trial teams are made up of doctors, nurses, pharmacists, research assistants and other healthcare professionals who are trained in clinical medicine and in proper conduct of clinical trial research. The person in charge of the clinical trial, usually an oncologist, is called a principal investigator.

A clinical research associate or clinical research nurse on the team is there to help support you during treatment. This includes answering your questions, monitoring your health during the trial and helping you understand what will happen during the clinical trial.

Who can be in a trial?

Clinical trials often enrol people who share many of the same characteristics. This is to make sure that the trial results will be scientifically accurate. The rules about who can be in a trial are called eligibility criteria.

The eligibility criteria may include:

  • age and sex
  • the type of cancer
  • the stage of the cancer
  • the results of certain lab tests
  • your overall health and whether you are being treated for other health problems
  • how many and what types of cancer treatments you have received
  • how long it has been since you last had treatment

These criteria also help researchers understand who will benefit most from a new treatment. For example, a new treatment may work for one cancer but not another or it may work best at certain stages of cancer.

Informed consent

You should be given all the facts about a clinical trial before you decide to take part. This important process is known as informed consent.

People interested in taking part in the study receive a printed consent form that outlines key facts about the study. These include details about the treatments and tests and any potential benefits, risks or side effects.

If you agree to take part, you will be asked to sign the informed consent form. Even after you have signed an informed consent form, you can withdraw from participating in a clinical trial at any time.