This section provides answers to some frequently asked questions about clinical trials. If you think something is missing or if you know of something helpful that should be part of this section, please let us know.
We have tried to make the language on this site as easy to understand as possible. There are still some terms that you might find helpful to have defined, so we have included those in alphabetical order below. We will add more terms and definitions if we get feedback from you about this.
Biologics are drugs that are made by a living organism such as cells or animals. They can include blood and blood products, micro-organisms, vaccines, hormones and cell-based products.
Blinding is when you do not tell someone which treatment they will receive, for example the treatment being tested or a placebo. Single-blinded means that the participants do not know which treatment they receive in a clinical trial, but the investigator or person running the clinical trial does know. Double-blinded means that both the participant and investigator/person running the clinical trial do not know which treatment is being used. Blinding helps makes sure that personal opinions or perceptions do not affect the clinical trial results (this is called bias).
A case control study allows a comparison of people who have a specific disease with a group of people without a disease. The people with the disease being studied are called the cases and the people without the disease are called the controls.
Clinical research is research that involves people who voluntarily participate, or research that is done on samples provided by volunteers such as blood or tissues. Clinical trials are a type of clinical research that involve an intervention that could be a drug, a procedure or a device, or a change to someone’s lifestyle such as exercise or diet. Clinical trials are used to determine safety and effectiveness of treatments, devices and procedures and this website focuses mainly on clinical trials. Observational studies are a type of clinical research in which researchers observe health over time in people without an intervention, for example, how smoking affects blood pressure or quality of life.
The diagram here shows the relationship between clinical research and clinical trials and observational studies. Terms that are used in the diagram are defined for you in this glossary.
A cohort study is where a group of people called a cohort is observed over time. A cohort is a group of people who are similar in some way, for example they have the same disease, are the same age, or the same gender. Cohort studies allow researchers to gather information on a large group of people and to follow them over a long period of time.
A control group is the group that the experimental group is compared to and may also be called the control arm. The control group may receive a placebo and be compared against the experimental group that received the experimental treatment. Or the control group may receive the standard treatment while the experimental group receives the standard treatment and the experimental treatment. By looking at the differences between the control and experimental groups, researchers can understand the effect(s) of the experimental treatment.
Database research involves the review and analysis of information that is stored in a database. For example, a researcher may be interested in seeing how many people over the age of 80 who live in a certain area have gone to the ER with a complaint of chest pain in the last year. In this case, hospital databases would be able to provide this information.
Decision rule research aims to create a better way of diagnosing and/or treating certain conditions so that healthcare providers can provide consistent care to specific groups of people or to predict better outcomes for their patients.
A device trial is research in which an instrument or device is being tested for safety and effectiveness. Devices may be used to diagnose diseases, treat diseases, or repair or replace part of the body.
A drug trial is a set of procedures followed in medical research and drug development to determine the safety of a product and obtain information about any reactions that a person may have to the drug being tested. Drug trials determine if a drug is effective in treating certain conditions or certain populations such as children or the elderly.
Eligibility criteria are characteristics that possible participants must meet in order to participate in the clinical trial. Inclusion criteria are the reasons that allow a person to participate in a clinical trial, for example, they are a certain age range and have a specific medical condition. Exclusion criteria are the reasons that do not allow a person to participate, for example, a clinical trial may only be for males, so an exclusion criterion would be ‘female.’
An experiment is a study that is done that follows a ‘recipe’ by changing one thing at a time so that you can determine cause and effect. Experiments are done to confirm an assumption or idea.
Good Clinical Practice (GCP) guidelines are an internationally accepted set of standard rules for conducting clinical trials. These guidelines ensure that all clinical trials follow the same rules, no matter where they are done in the world. GCP guidelines provide assurance that the rights, safety, and well-being of clinical trial participants are protected, and that clinical trials are done with a high level of quality.
Research in drugs, biologics, devices and natural health products that is done with human participants is overseen or regulated by Health Canada. Health Canada has a set of rules that must be followed when conducting clinical trials in addition to following GCP guidelines. These rules ensure the safety of all participants in clinical trials. Health Canada inspectors may visit clinical trial sites to review ongoing research and to ensure that regulations are followed.
Informed consent is the process where you learn details about the clinical trial before deciding whether or not you wish to take part. This includes learning about the clinical trial’s purpose, who is sponsoring the clinical trial, who has reviewed and approved the clinical trial, how long it will last, possible benefits and risks, how the clinical trial might affect your daily life, potential reimbursement of costs, additional tests and treatments, the criteria that define if you are eligible for the clinical trial, and who will be in charge of the clinical trial and your care.
Anyone who decides to take part in a clinical trial must provide their consent before the clinical trial begins by signing a consent form. You will be given a consent form with all of this information on it to keep and to go back to if you need it at some point. This aims to make sure that you understand the clinical trial’s purpose, what will happen when the clinical trial is underway, and are kept informed as the clinical trial progresses. The consent form will also have important study information listed in case you need it.
In some cases, a legally appointed guardian will be asked to provide informed consent, for example, the parent of a child or a guardian of someone who cannot make their own decisions.
Interim analysis is when data collected in the clinical trials are analyzed before a clinical trial is complete. If the researchers find that the new treatment is especially beneficial or harmful to participants compared to the placebo or standard treatment, they are obligated to stop the clinical trial.
Natural health products are vitamins, minerals, herbal medicines, probiotics, energy drinks, and other homeopathic supplements that may be used to treat a medical condition.
Non-regulated research is clinical research considered to have less risk. This research is often observational which means that information is collected by reviewing medical charts or from questionnaires or surveys. An interventional study using exercise or diet as the intervention would also be considered non-regulated research. These studies do not require approval from Health Canada.
People who volunteer to participate in clinical trials are called participants. Participation in clinical trials is strictly voluntary, and you can read other parts of this website to understand a participant’s rights and role in the clinical trial.
Clinical trials are usually done in a series of steps or phases so researchers can learn about new medications, treatments and devices in a gradual and safe way. Information and results from one phase are used to help design the next phase. No treatment moves from one phase to another unless the previous phase’s results were successful.
Phase 1 studies involve 20-80 people. This is generally the first time these medications are given to people. Healthy people take the treatment to ensure it is safe, determine how much is needed, and to determine side effects. Sometimes this phase occurs in people with a disease such as cancer.
Phase 2 studies involve 100-300 people. People with the medical condition being studied are watched to see if the treatment works as expected and further evaluate safety and dose.
Phase 3 studies involve 1000-3000 people. Larger groups of volunteers are monitored to continue observing side effects and to see how well a treatment works in the long-term, how long its effects last, and how it compares to current treatments or a placebo.
Phase 4 studies involve a large population. After a treatment is shown to work and is approved, the long-term effects and safety are studied and to determine if existing therapies should be replaced.
A placebo is a pill, liquid or powder that has no treatment value – that is, it has no medicinal ingredient in it, but it looks just like the medicine that is under investigation. In clinical trials, experimental treatments are sometimes compared with placebos to see how well the experimental treatment worked or did not work. Not all clinical trials use placebos since sometimes it is considered unethical or harmful to participants if they are taken off of a medication to take a placebo instead. Placebos are not usually used for participants with life-threatening illnesses such as cancer or for participants who may suffer very serious consequences if they are taken off their medications (such as people who have rheumatoid arthritis).
You can think of the protocol as the study or project plan, study instructions or the how to manual. It includes information about the reason for doing the clinical trial, who can participate in the clinical trial, how many people are needed, what medication(s) or treatments will be given, how they will be given, the dose and how often they will be given, what medical tests will be done and how often, and what types of information will be collected. The protocol will also outline who is in charge of the study and the roles and responsibilities of the participants and healthcare professionals who are part of the clinical trial team. The protocol is not usually given to the participants in a clinical trial.
Often as part of clinical research and trials, researchers measure quality of life or QoL and how a treatment or medication affects this. Quality of life is a person’s opinion of the overall quality of their daily life. Participants are asked to answer questionnaires that help researchers understand how a treatment or medication affects them emotionally, socially and physically.
Randomization is when participants are assigned by chance alone, that is randomly, to different treatment groups, just like flipping a coin or taking a number out of a hat. For instance, in a clinical trial one group would receive the standard treatment (control group) and the other group would receive the experimental treatment. Individuals are assigned to groups by chance to help prevent bias in results that may occur if participants were assigned to a group by a person.
A registry is a system for collecting and storing information about people who have a disease, have been exposed to a certain medical intervention, or have something that puts them at risk for developing a disease or condition. Information is registered and collected to learn more about how this affects a person’s health and/or lifestyle.
The Research Ethics Board is an independent group that reviews the ethics (the right and wrong) of a research study or clinical trial and ensures the participants are protected. In the United States REBs are called Institutional Review Boards or IRBs.
In Canada an REB has at least five members, including both men and women, of whom:
The REB tries to make sure that:
Approval to begin a clinical trial is given only when the REB is satisfied that all of its questions have been answered. Participants have the right to contact the REB at any time if they are uncomfortable with any aspect of the clinical trial, have any questions about their role and rights, or have concerns or complaints about the clinical trial.
Being recruited to participate in a clinical trial means that you meet the list of requirements to participate and you have decided to participate in the clinical trial. For example, you may have to be a certain age, on certain medications already, or have a certain chronic illness to participate in the study. Recruitment for a clinical trial is the process of approaching participants to take part in the clinical trial and getting their consent to participate.
Experts review protocols before clinical trials start to make sure that they are based on good science and will actually measure what they set out to measure or compare. This step is done before the REB reviews the clinical trial.
The person, company or organization that starts and manages a clinical trial, and if required, applies for permission (e.g., from Health Canada) to conduct the trial. The sponsor may or may not provide financing for the clinical trial. The sponsor can be a pharmaceutical or biotech company and sometimes it is also a disease foundation or a charity.
Surveys and interviews provide information to researchers about how people think about the world, how they act and behave in it, and how and why people interpret and understand what they say and do.
Sometimes as part of a clinical trial or research project, a participant will be asked to donate tissue, for example from a tumour or a biopsy. This sample may be studied with different methods, such as genetic or genomic methods, or even made available to other researchers at a later date to study with technologies that may currently be unknown. Any information about the intended use for this sample will be in the informed consent form provided to participants.
Here we have tried to answer some common questions that people ask about participating in clinical trials.
There are many ways you can get in to a clinical trial. For example, your physician may approach you or you can ask your physician or your healthcare team yourself if there is a clinical trial that they can help you find. If you find a clinical trial that you would like to be in that is not in your location, you can also ask your physician if it is possible for him or her to open the clinical trial at their centre, or you can ask them to refer you to another centre that is conducting a clinical trial. It is important to know that even though you wish to be in a clinical trial, you must meet the eligibility criteria to be part of the clinical trial and it is sometimes not possible for your physician to open the clinical trial at his or her centre.
Here are some trustworthy resources to help you find a clinical trial.
You may also find out more about how to be in a clinical trial by asking your doctor or another member of your healthcare team.
The drug, treatment or device in a clinical trial is usually free, however sometimes the drug, treatment or device it is being compared to is not free. Costs you might also need to consider are for travel (to and from the clinical trial site), childcare, lost income due to time away from work, parking, and others. A clinical research coordinator can help you determine your costs over the clinical trial and if they are reimbursed by the sponsor. This might help you decide if participating in the clinical trial will work for you or not.
Clinical trials can last for different amounts of time. The length of time for a participant (the time that a single person is involved in a trial) is different from the entire duration of the clinical trial (the amount of time it takes for the trial to reach its enrollment number). You can ask how long a clinical trial will be before you start it to help you determine if it is right for you. Some clinical trials last for years.
Yes, you can choose to leave a clinical trial at any time – this is completely up to you. Leaving the clinical trial will not affect your usual medical care that you receive outside of the clinical trial. This is also called withdrawing from a clinical trial.
Yes, you will still be seen by your regular attending physician (this might be your family doctor, a specialist, etc.) as well as by the clinical trials team while you are in the clinical trial.
You will still receive your regular medical care while you are in a clinical trial. You will also receive additional care and tests that are part of the clinical trial. This additional care will depend on what the clinical trial is and will be different for different trials. This additional care will not cost you anything, except for your time to receive it or perhaps travel costs (which may be reimbursed).
These are some things you may wish to do when you are participating in a clinical trial – these have been provided by people who have either been in a clinical trial or had a family member in a clinical trial:
Clinical trials sometimes end early. This may be because:
There are many safeguards in place to protect you and other participants in clinical trials, and as much as possible, attempts are made to minimize risks. Some of the safeguards to protect participants in clinical trials include:
Side effects are consequences of a treatment that are not related to the original intended benefit of the treatment. Side effects can be both positive and negative.
Adverse effects or events are consequences of a treatment that are not related to the intended benefit of the treatment and are harmful.
Both side effects and adverse effects are not always predicted by researchers carrying out clinical trials and must be reported as part of the clinical trial results. Sometimes these side effects or adverse events are very minor but they can even be life-threatening, and in this case they are called serious adverse events. Serious adverse events are reported to REBs and Health Canada and may stop a clinical trial until it is understood how they are properly dealt with and if it is safe to proceed again. Any future or current participants are told about adverse side effects if they happen during a clinical trial.
It is possible that you will experience side effects when you participate in a clinical trial. Your clinical trial team will discuss with you what you may expect and the informed consent form you sign will include this information. The Research Ethics Board will review the potential side effects in great detail to ensure the risks to you are minimized and that mechanisms are in place to manage the side effects. This will include providing you with contact information and where to seek help. In all cases, you should follow the informed consent form instructions on side effects including the contact information provided.
When you are participating in a clinical trial, personal health information from your original medical records and all data resulting from your participation is collected. Your personal health information may include physical exam details, blood test results, x-rays, other medical procedures, or tissue samples. Your identity is always protected through a system that de-identifies participants: your name and contact details will never be disclosed, unless required by law.
One of the key ethical challenges for the health research community is to protect the privacy of individuals whose information is used for research purposes. Safeguards and procedures are put in place, such as:
There are very strict guidelines around information and privacy in a clinical trial – all members of the clinical trial team have obligations.
Keep in mind that most clinical trials take time to complete – often years. This is because a clinical trial may be run at a number of different sites, across different phases, and with a large number of participants. So even if your participation in the clinical trial has ended, the clinical trial may still be ongoing. You can ask the clinical trial team for the results or sometimes you can find the results published online.
Accessing a phase 1 or 2 clinical trial for treatment in another province for which you meet the eligibility criteria may require the approval from your provincial health jurisdiction in order for medical expenses to be paid by the provincial body and not by you yourself. For example, if you live in BC and are eligible for and accepted in to a clinical trial in Ontario, you may need to receive approval from the Medical Services Plan in BC before going to Ontario to start the clinical trial. The application for out of province treatment is usually submitted by your physician or another member of your healthcare team. It is important to speak up for yourself to ensure that the proper paperwork is submitted and done in a timely manner. You may need to help with gathering medical records or other health related information for the application.
Provinces may have regulations about accessing early phase (1 and 2) trials and often consider these to be “experimental.” Accessing a phase 3 or 4 clinical trial that is out of province may be funded without much delay as long as the need for it can be justified.
If there is a clinical trial in another part of the world that you would like to access, for which you meet the eligibility criteria, and which has accepted you as a participant, you must follow a similar process as outlined above. There may be more work required on your behalf, such as providing related articles from peer reviewed medical journals, letters of support from your home and treating hospitals, and other documentation. It may also be valuable to have your home and treatment hospitals work together so components of the treatment and diagnostic testing may be done at your home hospital to reduce costs and the amount of time that you must be away from home.
Specific to clinical trials, it is important to note that if approval is given to access treatment through a clinical trial in another province or outside of Canada, only the costs of the actual treatment will be covered. Travel to and from the treatment hospital, lodging costs, food, and any other non-treatment related expenses are typically not covered by your provincial health body. These costs and the time that you will be away from home and work, are factors to weigh when considering a clinical trial that is not in your home province.
If a clinical trial is not available for your illness or medical condition, this is a very difficult situation. However, there may be an opportunity to advocate for research to be done. Speak to your healthcare team, ask questions, find out if there is research currently being conducted in a laboratory, ask if there is anything promising on the horizon, and find out if there is anything that you can do to help bring a clinical trial to your province, or to Canada. Connect with organizations that are supportive of your disease or medical condition.
There also are other possible risks associated with taking part in a clinical trial, for example in a clinical trial that includes genetic testing there can be a risk in knowing genetic information. New health information about inherited traits that may affect you or your blood relatives could be found during a study.
In some cases these results could be used to make it harder for you or your relatives to get or keep a job or to have insurance. The chance that these things will happen is very small, but researchers cannot promise that they will not occur, and employers or insurance providers may ask if you have had these genetic tests done.
Often clinical trials take place in more than one country at the same time. So although you are participating in one location, the data collected from you and others participating at that location may be combined with participants from many other locations around the world who are all taking part in the same clinical trial.
This section answers some questions about who comes up with the ideas for clinical trials and general information on running clinical trials.
Ideas for clinical trials come from researchers, scientists, physicians, and sponsors who may work at universities, who are independent researchers, or who work for pharmaceutical or biotech companies. After researchers test new therapies or procedures in the laboratory and in animal studies, the experimental treatments with the most promising results are moved into clinical trials.
Clinical trials are designed by doctors, researchers, scientists, sponsors, and other specialists with input from many people, and sometimes from patients. First they decide what questions need to be answered, and then they design a protocol that they believe will answer these questions.
Under Health Canada’s regulations, a qualified physician or dentist can conduct a clinical trial.
Clinical trials are sponsored or funded by a variety of organizations or individuals, such as physicians, medical institutions, foundations and charities, pharmaceutical and biotech companies and federal agencies.
Clinical trials are overseen by a number of different bodies that focus on different aspects of the study. In Canada, Health Canada is the regulatory agency that evaluates the science and study design, and has the final say on whether or not a treatment meets their criteria for it to be approved for use and sale in Canada.
This section includes more information for you about clinical trials, including ideas for you on how to reach out to other groups that conduct clinical trials.
The British Columbia Clinical Research Infrastructure Network (BCCRIN), the Canadian Clinical Trials Coordinating Centre, and N2 are working to engage and learn from patients and the public about the clinical trial process. Through a survey, we are reaching out to the public to provide input and advice on their experience with clinical trials, especially people who have declined to participate in a clinical study. To participate in the survey, please click here.
Click here to see N2’s pamphlet about clinical trials.
Many health charities and disease organizations can help you if you are interested in participating in a clinical trial and are not sure how to get in to one. Some disease organizations or foundations fund their own clinical trials and this information will be on their website.
There are many groups that work together (sometimes they are academics and industry) to do clinical trials. Some of them are listed here and feel free to contact them for information on how to be in a clinical trial that they are undertaking: