What to Expect at Your First Clinical Trial Screening Visit
You've found a clinical trial that looks like a good fit. You've spoken to your doctor, read the summary, and expressed interest. The next step is the screening visit — and if you've never done one before, it's natural to feel uncertain about what's actually going to happen.
This guide walks you through the entire process so you can arrive prepared, confident, and ready to ask the right questions.
What Is a Screening Visit?
A screening visit is the research team's way of checking whether you're eligible to take part in a specific trial. It's not a commitment — it's an evaluation. Both sides are figuring out if the trial is a good match for you.
The visit is usually held at the hospital or research centre running the trial. It typically lasts between one and three hours, depending on how many tests are needed.
Key point: Attending a screening visit does not mean you've joined the trial. You are still free to say no at any point — even after all the tests are done.
Before the Visit: What to Bring
The research team will usually send you a list, but here's a reliable checklist:
- NHS number and a form of photo ID (passport or driving licence)
- A list of all medications you currently take — including over-the-counter medicines, supplements, and herbal remedies
- Medical history details — previous diagnoses, surgeries, allergies, and vaccinations
- Your GP's name and contact details
- A friend or family member — you're welcome to bring someone for support. They can sit in on discussions and help you remember what was said
- A notepad and pen — there will be a lot of information, and writing things down helps
- Reading glasses if you use them — you'll be reading paperwork
If you take regular medication, bring the actual packaging or a photo of each box — including the dosage. It's more reliable than trying to remember from memory.
What Happens During the Visit
Every trial is different, but most screening visits follow a similar structure. Here's what to expect, step by step.
Welcome and introduction
You'll meet the research team — usually a research nurse or clinical research coordinator, and sometimes the principal investigator (the doctor leading the trial). They'll explain who they are, what the visit involves, and roughly how long it will take. This is a good time to mention any concerns or accessibility needs.
Detailed study explanation
The team will walk you through what the trial is testing, why it matters, and what participation would actually look like day to day. They'll explain the treatment or intervention, how often you'd need to visit, what tests are involved during the trial, and how long the whole thing lasts. If there's a chance you could receive a placebo, they'll tell you. Nothing should be vague or glossed over.
Informed consent
This is the most important part of the visit. You'll be given a consent document — often 10 to 20 pages — that covers the trial's purpose, procedures, risks, benefits, alternatives, your rights, and who to contact with questions. The team will go through it with you section by section.
Take your time. You do not have to sign anything on the day. Many people take the consent form home to read thoroughly and discuss with family or their GP before deciding.
Medical assessment
The research team will check whether you meet the trial's eligibility criteria. This usually involves:
- Physical examination — blood pressure, heart rate, weight, height, and a general check
- Blood tests — to check organ function, blood counts, and sometimes specific biomarkers
- Urine sample — common for many trials
- ECG (heart trace) — quick and painless, takes about five minutes
- Review of your medical history — they'll go through your records in detail
Some trials may require additional tests like scans (CT, MRI, X-ray), breathing tests, or questionnaires about your symptoms and quality of life.
Questions and next steps
The team will ask if you have questions — and they genuinely want you to ask. There are no silly questions. They'll also explain what happens next: how and when you'll be told if you're eligible, when the trial would start if you qualify, and who your main contact will be throughout.
Questions Worth Asking
It helps to prepare questions in advance. Here are some that are always worth raising:
- What exactly is being tested, and has it been studied before?
- What are the most common side effects, and how are they managed?
- How many visits will I need, and how long is each one?
- Will I need to stay overnight at any point?
- Can I continue taking my current medications?
- Will participating affect my normal NHS treatment?
- What happens if the treatment causes problems — who do I call?
- What happens at the end of the trial — will I still have access to the treatment?
- Is travel reimbursed?
- Can I see my test results?
After the Visit
The research team will review your test results against the trial's eligibility criteria. This can take anywhere from a few days to a couple of weeks, depending on what tests were needed.
There are three possible outcomes:
- You're eligible and want to proceed — you'll be enrolled and given a schedule for your first treatment or baseline visit.
- You're eligible but decide not to participate — that's completely fine. No explanation needed, and your regular care continues unchanged.
- You're not eligible — this is common and not a reflection on you. Eligibility criteria are strict by design. The team may be able to suggest other trials that could be a better fit.
Remember: The screening visit is as much for you to evaluate the trial as it is for the team to evaluate you. Ask questions, take notes, and never feel pressured to decide on the spot.
A Few Things That Surprise People
- It's more thorough than a regular appointment. The research team will spend significant time with you — often much more than a standard clinic visit.
- You can say no. Even after all the tests, even after the team has spent hours with you. Withdrawing interest is always your right.
- You might get paid for your time. Healthy volunteer trials and some patient trials offer compensation for travel and time. The team will tell you upfront.
- The team is on your side. Research staff chose this career because they want to help patients. They are not trying to recruit you at all costs — they want the right people in the right trial.
A screening visit is a conversation, not a commitment. Go with an open mind, ask every question you have, and take the consent form home to read properly. Whatever you decide, you'll leave knowing more about your options than you did before — and that's always a win.