So, you’ve come across a clinical trial that sounds interesting-or maybe one that could offer a potential treatment option for your condition-and you’re curious about what happens next.
Before you’re officially enrolled in a clinical trial, you’ll go through a screening process. This is not just about the researchers deciding if you’re the right fit-it’s also about you deciding whether the trial is right for you.
If you’ve never participated in a clinical trial before, this guide will walk you step-by-step through what to expect during the screening and medical evaluation process in Canada, including a detailed look at one of the most important steps: informed consent.
1. The Initial Sign-Up or Phone Call: First Contact
What Happens:
Once you’ve identified a trial that interests you-either through Research Connect CTR, your doctor, a hospital, or a clinical trial registry-you’ll either:
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- Fill out an online form
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- Call a research coordinator directly
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- Be contacted by the study team if you were referred
The first phone call is typically brief, lasting 10–20 minutes. This is known as a pre-screening.
Purpose of the Call:
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- To determine if you meet the basic eligibility criteria (age, sex, diagnosis, medications, lifestyle, etc.).
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- To explain the goal of the study in general terms.
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- To describe what participation would involve (e.g., visits, procedures, time commitment).
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- To see if you’re interested in proceeding.
Sample Questions They Might Ask:
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- Do you have any known medical conditions (e.g., asthma, diabetes)?
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- Are you currently taking any prescription or over-the-counter medications?
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- Do you smoke, drink alcohol, or use recreational drugs?
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- Are you pregnant, breastfeeding, or trying to conceive?
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- Are you available to come to the clinic at specific times?
Your Role:
This is your opportunity to ask any questions-about the study, the time commitment, risks, or even compensation. Don’t be shy; it’s your body, your time, your decision.
2. Invitation for Screening: Next Steps
If the pre-screening call goes well, you’ll be invited for an in-person (or occasionally virtual) screening visit.
The screening visit is like a thorough health check-up combined with a decision-making meeting. It ensures:
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- You consent voluntarily with all your questions answered.
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- You qualify for the trial based on your health, lab work, and personal history.
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- You’re fully informed before you agree to participate.
3. Informed Consent: The Most Important Document You’ll Sign
Before anything medical happens, you’ll be introduced to the Informed Consent Form (ICF).
What Is It?
The Informed Consent Form is a detailed, legally required document that explains:
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- The purpose of the study
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- How long it will last
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- Any possible risks, side effects, or discomforts
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- The potential benefits (if any)
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- Your rights as a participant
Signing It Doesn’t Mean You’re Locked In
Informed consent is not a contract-it’s an agreement that you understand everything and agree to move forward. You can withdraw your consent at any time, even after signing and even after starting the trial.
Your Rights During Informed Consent:
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- You can take as long as you need to review the document.
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- You can ask unlimited questions.
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- You can bring a family member, friend, or legal advisor with you.
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- You must be given a copy of the signed document.
Tip: Don’t just skim the consent form. Take your time. Highlight things. Ask questions. This is your body and your health-you deserve clarity.
4. The Screening Visit: Your Medical Check-Up
Once you’ve signed the Informed Consent Form, you’ll move into the medical screening phase. The study team needs to make sure you’re medically eligible to participate.
What Happens During Screening?
The specific tests and assessments vary depending on the trial, but they usually include:
A. Medical History Review
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- Your past diagnoses, surgeries, medications, and treatments
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- Family history of major illnesses
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- Vaccination status
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- Allergies
Be honest-even small things like vitamins, birth control, or recreational cannabis use may be relevant.
B. Physical Examination
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- Height, weight, body mass index (BMI)
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- Blood pressure, heart rate
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- Respiratory rate and temperature
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- General health check (e.g., eyes, ears, throat, reflexes)
C. Laboratory Tests
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- Blood work: CBC (complete blood count), liver/kidney function, cholesterol, blood sugar, etc.
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- Urine test: For kidney function, drug screening, or pregnancy
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- Optional tests: Depending on the study-this could include saliva, stool, or genetic testing
If the trial is testing a new drug, researchers may need to understand how your metabolism or DNA might influence your response.
D. Imaging or Diagnostic Tests (if applicable)
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- ECG (electrocardiogram) to check your heart rhythm
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- X-rays, MRIs, or ultrasounds
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- Pulmonary function tests (PFTs) if it’s a respiratory study
E. Cognitive or Psychological Screening
If the study involves the brain, memory, or mental health, you might be asked to complete:
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- Mood or anxiety questionnaires
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- Memory or attention tests
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- Interviews with a psychologist or psychiatrist
F. Exclusion Criteria Check
Some conditions automatically disqualify you from participation for your own safety or for scientific reasons. This could include:
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- Certain chronic illnesses
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- Abnormal lab results
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- A history of substance abuse
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- Recent participation in another trial
Important: Being excluded doesn’t mean you did something wrong. It just means the study needs a very specific type of participant, and you may not meet that profile right now.
5. Time Commitment and Logistics: What to Prepare For
During the screening process, the study team will also go over the time commitment required if you’re enrolled.
They’ll discuss:
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- How many clinic visits are required
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- How long each visit will last
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- If there are overnight stays
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- Whether you’ll need to take medication at home
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- Dietary or lifestyle restrictions (e.g., no alcohol, no grapefruit, etc.)
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- Reimbursement for travel, time, or childcare
At this point, you’re still free to say yes, no, or “maybe later.”
6. Screening Outcomes: What Happens After the Visit
Screening is not a guarantee of enrollment.
After your screening visit:
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- Your results are reviewed by the study team and possibly the sponsor.
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- You may be approved and officially enrolled.
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- You may be excluded (and told why).
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- You may be placed on a waitlist or offered a future study.
If you qualify and choose to move forward, you’ll typically receive a study calendar, instructions, and a dosing schedule if the trial involves medication.
7. Tips for a Smooth First Experience
Here’s how to prepare for your screening visit and make it as stress-free as possible:
Bring ID and medical records (if available)
Write down all your medications and supplements
Arrive early and well-rested
Eat and drink as instructed (some tests may require fasting, but drink plenty of water!)
Bring a support person-especially if the form is long or technical
Be completely honest-this protects your safety.
8. The Importance of Informed Consent (Again!)
Let’s return to the Informed Consent Form, because this is where ethical clinical research begins and ends.
Informed consent is not a checkbox; it is a process.
It’s your assurance that:
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- You are volunteering freely
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- You know the risks and benefits
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- You have no obligation to participate
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- You can withdraw anytime
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- Your data and privacy are protected
Every participant, no matter their background, age, or education, deserves to fully understand what they’re signing up for.
If something in the consent form confuses you-ask. If it feels rushed-ask to slow down. If you’re unsure-take it home to review. Your informed consent is a partnership, not a permission slip.
9. You’re Not Alone: Support During Screening
Most Canadian clinical trial sites have:
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- Study coordinators to guide you through logistics
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- Nurses and physicians trained in clinical research
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- Ethics boards overseeing your rights and safety
You’ll never be left to figure it out on your own. Ask questions. Voice concerns. Be heard. It’s your trial experience.
Lastly-Screening Is a First Step, Not a Commitment
Joining a clinical trial isn’t like joining a gym. It’s a meaningful decision about your health and your role in scientific discovery.
The screening process exists to:
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- Protect you
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- Educate you
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- Help you decide with confidence
Whether you go on to participate or not, the screening visit itself is a valuable, eye-opening experience that many find empowering and educational.
Key takeaway: Screening isn’t about jumping into a study-it’s about gathering all the information you need to make an informed choice about your health, your time, and your contribution to medicine.
References
Canadian Cancer Society. (n.d.). Understanding the clinical trial and informed consent. Retrieved from Canadian Cancer Society website Canadian Cancer Society
Health Canada (2024, April 5). Research Ethics Board: Consent process. Government of Canada. Retrieved from Health Canada website Canada
National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health. (n.d.). Clinical research regulation for Canada. ClinRegs. Retrieved from ClinRegs website clinregs.niaid.nih.gov
McGill University Health Centre (MUHC). (n.d.). A guide to understanding informed consent. Retrieved from Research website Wikipedia+4rimuhc.ca+4Canadian Cancer Society+4
Canada Council of Research (Treasury Board of Canada Secretariat). (2023, January 11). TCPS 2 (2022) – Chapter 3: The consent process. In TriCouncil Policy Statement: Ethical conduct for research involving humans (TCPS 2). Government of Canada. Retrieved from ethics.gc.ca Verywell Health+13ethics.gc.ca+13Canada+13
Multiple Sclerosis Canada. (n.d.).
Introduction to clinical trials. Retrieved from MS Canada website Wikipedia+6mscanada.ca+6Health+6
Merck Clinical Trials. (n.d.). How to take part in a clinical trial. Retrieved from Merck Clinical Trials website Merck Clinical Trials
Horizon Health Network. (2015). General information you need to know when participating in a research study [PDF]. Retrieved from Horizon Health Network website Horizon Health Network
Genesis Research Services. (2018, May 10). Clinical trials – the screening process. Retrieved from Genesis Research Services website Wikipedia+15Genesis Research Services+15mscanada.ca+15
AbbVie Clinical Trials. (n.d.). Screening visit virtual tour. Retrieved from AbbVie Clinical Trials website abbvieclinicaltrials.com+1 AbbVie Clinical Trials. (n.d.). Clinical trial journey. Retrieved from AbbVie Clinical Trials website abbvieclinicaltrials.com
College of Physicians and Surgeons of Canada (CMPA). (n.d.). Consent: A guide for Canadian physicians.
Hinterhaus Productions/Getty Images. (2023, September 6). What are clinical trials? Health.com. Retrieved from Health.com Health
StatPearls Publishing. (2022). Informed consent. In StatPearls. Retrieved from StatPearls Wikipedia
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