What is Clinical Research?

Clinical research, sometimes called clinical studies, is done to help researchers better understand, prevent, or test treatments for different conditions in humans.

Types of Clinical Research 

Generally, there are two types of clinical research: clinical trials and observational studies. Both are described below. For both clinical trials and observational studies, researchers set out specific criteria that people need to join their study, such as a specific age range, types of conditions, medications they are taking, etc. The research team, led by a medical doctor, will inform you of whether you are a good fit for the study based on their study plan.

Clinical Trials

Studies that test possible treatments are known as interventional studies or clinical trials. In these studies, researchers test a new treatment or 'intervention' such as a drug, medical device, technique or change in lifestyle that they think will benefit people living with a specific condition.

For instance, a clinical trial in the field of dementia may look at whether a computer game aimed at improving thinking and memory can help to prevent dementia in people with a family history of Alzheimer’s disease.

In clinical trials, participants are randomly assigned to a group and will receive either the intervention being tested or a 'placebo'. A placebo is something that seems to be an exact copy of the intervention but is not active (e.g., a sugar pill). In some cases, there are treatments available that a person could benefit from, and giving a placebo can take away that benefit and potentially cause harm. In these cases, participants will receive the typical care for that condition instead of the placebo, allowing researchers to see whether the intervention they are testing is better than what is currently available. 

Often, participants are not aware of which group they will be assigned to, which is a process known as 'blinding'. Members of the research team who interact with participants may also be blinded (i.e., they don’t know whether the participant is receiving the treatment or placebo). Blinding helps to ensure the outcomes of the study are not influenced by knowing which participant is receiving treatment or not.

The overall goal of clinical trials is to see if receiving the intervention is more effective and safe than not receiving the intervention, or than receiving the best treatment currently available. Researchers conduct these trials to find out whether the inventions are helpful, but unfortunately, they may also cause side effects or have no effect.

Clinical trials involve four different phases of studies:

Phase 1 Studies

Test the safety and ideal dose or usage of the intervention in humans for the first time. These trials are often shorter in length, generally lasting a few months, and usually in healthy volunteers (e.g., people without memory problems). Phase one studies often include about 20 to 80 participants.

Phase 2 Studies

Look at whether an intervention works and is safe in people living with the condition. Phase two studies often include about 100 participants or more.

Phase 3 Studies

Look to confirm whether an intervention is safe and effective in a larger number of participants living with the condition (around 1,000 participants or more). Outcomes are compared to a group that either receives a placebo, no treatment, or the typical care for that condition. In order to move onto phase four, the intervention must be at least as safe and effective as existing care options.

Phase 4 Studies

Occur after the treatment has been approved for use by Health Canada (i.e., the treatment is available for doctors to prescribe to patients). Phase four studies look at long-term safety, how effective the treatment is, and best practices for using the treatment in real-world settings.

It is important to know what phase a clinical trial is in and what that means for you or your loved one as a potential participant. Find out more about the different phases of testing in a clinical trial.

Observational Studies

Observational studies are designed to provide researchers with a better understanding of a condition. Participants do not receive any intervention (e.g., no drug, device, technique or lifestyle approach) in observational studies. These studies instead involve questionnaires and tests that allow researchers to gather more information on the condition and how it affects participants over the length of the study.

For instance, an observational trial may include yearly brain scans, thinking and memory tests, and blood tests for people living with different types of dementia  to identify how these conditions progress differently over time. 

Participating in Clinical Research

It is your choice whether you want to join a clinical study. You should never feel pressured to participate. All studies will ask for your informed consent before enrolling you in the study. This means that you are aware of what the study involves, potential risks and benefits, and you have a chance to ask questions. Once you are provided with this information, you can choose to enroll in the study by giving your informed consent. This may involve signing a form virtually or in person.

In cases of advanced dementia where the person is unable to provide consent, a substitute decision-maker may be asked to give consent on the person’s behalf. Substitute decision-makers are family member(s) or someone close to the person living with advanced dementia appointed to make health decisions for them.

Clinical studies can vary in length from months to years depending on the study plan created by the research team. If you no longer want to be part of the study at any point, you are free to leave and withdraw your consent.

The informed consent process, study plan, and other materials used in a study are reviewed by Research Ethics Board(s) at the hospital and/or university where the studies take place. The Research Ethics Board makes sure that participants are protected and risks are limited. Finally, it is important to note that your clinical care will never be affected by your decision to participate, or not to participate in research. 

Find out more information about clinical studies.

Why is Clinical Research Important?

Clinical research is a key way for researchers to advance our understanding of diseases. This is particularly important for conditions that we don’t know much about, or that don’t have treatments or cures. Depending on the type of study, the outcomes can help to improve the diagnosis, prevention, treatment, management and/or our knowledge of conditions. Clinical studies can also help researchers test and eventually develop new treatments, such as drugs, medical devices and lifestyle interventions.

To date, in Canada, there has not yet been an approved treatment that can stop or slow down the course of dementia. This does not mean that the field of clinical dementia research has slowed; quite the opposite. Getting involved in dementia research means that you can help researchers find new treatments and better understand dementia. Even when a treatment is found not to improve dementia symptoms in a clinical trial, it still provides researchers with key insights that can help them focus in on what might work (e.g., changing doses, length of treatment or the type of intervention).

For participants, clinical research can also provide you with access to treatments or medical testing beyond what is available from your healthcare provider. This can include interventions not approved by Health Canada, or brain scans and other tests not covered by the Ontario Health Insurance Plan (OHIP).

Why Participate in Clinical Research?

Being involved in a clinical trial can help researchers prevent, treat and/or better understand dementia. In clinical trials, you may receive a drug, medical device or lifestyle intervention that can help with your memory problems; however, there is also a chance that the treatment may not work or may lead to side effects. It is important that you understand what the study involves, the potential risks and benefits, and to have all of your questions answered before making your decision.

A number of helpful resources can help you make an informed decision about participating in clinical research, including:


Where Can I Find Out More About Clinical Research in Dementia?

The Toronto Dementia Research Alliance (TDRA) and the Alzheimer Society of Toronto have created listings of research studies that are open for participation across Toronto. These studies are looking for people with all types of memory and related problems, and for healthy volunteers too. You can find these listings on the Toronto Dementia Network (TDN) Research Studies Section.

Please note that this website currently lists clinical studies that are not sponsored by drug companies. Each study listed is led by one or more scientists affiliated with TDRA, and has been approved by a Research Ethics Board (REB).

You can also visit ClinicalTrials.gov to search through a world-wide listing of clinical studies looking for participants with many different conditions.

For more information on the TDN, read the brochure

For more information, visit the Toronto Dementia Research Alliance (TDRA) Blog! Learn more about the basics of clinical and scientific research, scientific concepts related to dementia, and TDRA researchers and their projects. You can also read about current TDRA research projects here