The informed consent document you sign before joining a clinical trial is legally required to answer many important questions — but it can run 20 pages of dense medical language, and it can't anticipate everything specific to your situation. Asking the right questions yourself, before you sign anything, is the most important thing you can do.
About this article: Educational and informational only. Does not constitute medical advice or eligibility guidance. Always discuss clinical trial participation with your physician before enrolling.
In This Article
- 1.Before Your First Call: Background Research Questions
- 2.Understanding the Trial Design
- 3.Safety and Risk Questions
- 4.Practical and Logistical Questions
- 5.Compensation and Cost Questions
- 6.Your Rights as a Participant
- 7.After the Trial Ends
- 8.How to Use This List
The best time to ask questions is before you agree to anything — ideally in a phone or video conversation with the research coordinator, before your first in-person screening visit. Research teams expect questions. A team that discourages them is a warning sign.
Print this list, add your own questions, and bring it to that conversation.
Before Your First Call: Background Research Questions
These you can often answer yourself before speaking to anyone, using the trial's public listing on ClinicalTrials.gov. If you can't find the answers, add them to your list.
Q1.What phase is this trial?
Why it matters: Phase 1 trials primarily test safety; Phase 2 tests whether the drug works; Phase 3 confirms efficacy in large populations. The phase tells you a lot about the risk level and what the researchers are still trying to learn.
Q2.What treatment is being tested, and what is it compared to?
Why it matters: Is the experimental arm compared to a placebo, to current standard of care, or to another active treatment? Knowing this helps you understand what you might receive.
Q3.What are the primary and secondary endpoints — what is the trial trying to prove?
Why it matters: A trial measuring "progression-free survival" is asking a different question than one measuring "symptom relief." The endpoint determines whether the trial succeeds and what it will demonstrate about the drug.
Understanding the Trial Design
Ask these questions of the research coordinator. They should be able to answer all of them clearly. If they can't, ask for time to read the protocol summary before deciding.
Q4.Is this trial randomized? If so, what are the odds I receive the experimental treatment?
Why it matters: In a 1:1 randomized trial, you have a 50% chance of receiving the experimental drug. In a 2:1 randomization, the odds are higher. Knowing this matters for your decision.
Q5.Is there a placebo arm? Could I receive only a placebo?
Why it matters: If a placebo-only arm exists, and your condition is serious, you need to understand whether that's acceptable to you and what access to treatment you'd have afterward.
Q6.Is the trial blinded? Will I or my doctor know which treatment I'm receiving?
Why it matters: Double-blind trials mean neither you nor your treating physician knows your assignment. This affects how symptoms and side effects are monitored and managed.
Q7.Is there an open-label extension? If the drug works, can I keep taking it after the trial ends?
Why it matters: Many trials offer continued access to the drug through an open-label extension (OLE) if it proves effective. This is especially important for chronic condition patients.
Safety and Risk Questions
These are the most important questions on this list. A transparent research team will give you direct, honest answers. Vague or dismissive responses are a red flag.
Q8.What are the most common side effects seen in this study so far?
Why it matters: Research teams accumulate safety data as the trial progresses. They should be able to tell you what participants have experienced — not just what the protocol predicts.
Q9.What are the most serious potential side effects? Have any serious adverse events occurred?
Why it matters: Serious adverse events (SAEs) must be tracked and reported. Asking directly shows you expect transparency, and the answer helps you weigh real — not theoretical — risk.
Q10.Is there an independent Data Safety Monitoring Board (DSMB) reviewing safety data?
Why it matters: A DSMB provides an independent check on safety separate from the sponsor. Its existence signals that the trial has rigorous safety oversight built in.
Q11.What happens if I experience a serious side effect? Who do I call, and at what hour?
Why it matters: The informed consent must include an emergency contact number. Confirm it exists and test that you can reach someone at any time — not just during business hours.
Q12.Can I continue my current medications while in the trial? Are there washout requirements?
Why it matters: Many trials require you to stop certain medications before or during the study. Stopping a medication you depend on is a significant decision that requires discussion with your regular doctor.
🛡️ Your Right to Full Safety Information
Federal regulation requires research teams to disclose all known risks before you consent. You are entitled to ask about risks discovered since the trial began — not just what was known when the protocol was written. If the research team is reluctant to share safety data that has accumulated during the trial, that is a compliance concern.
Practical and Logistical Questions
Time commitment and travel requirements cause more early withdrawals than side effects do. Know what you're committing to before you sign.
Q13.How long does the trial run? How many visits are required, and how long is each visit?
Why it matters: Phase 3 trials can run two to five years. Monthly clinic visits that each take four hours are a serious time commitment. Understand the full calendar before agreeing.
Q14.What procedures are required? Will there be biopsies, infusions, extra imaging, or blood draws beyond standard care?
Why it matters: Research procedures go beyond what your regular care would require. Some are minor; others (like repeat biopsies) are significant. You have the right to know everything that will happen to you.
Q15.Can I continue seeing my regular doctor? Will you coordinate with my care team?
Why it matters: Some trials require you to receive all care at the trial site. Others are flexible. Your regular physician should remain involved in your overall health management.
Compensation and Cost Questions
Q16.What costs will I incur? Will my insurance be billed for any trial-related care?
Why it matters: Under the ACA, insurers must cover routine care costs in qualifying trials — but the experimental drug itself is typically covered by the sponsor. Understand exactly what you'd owe out of pocket.
Q17.Is there compensation for my time and travel? How and when is it paid?
Why it matters: Most trials offer stipends for time and travel reimbursement. Know the amounts, the payment schedule, and whether compensation is taxable (it usually is).
Q18.If I am injured or experience a serious side effect, will the sponsor cover my medical costs?
Why it matters: Coverage for trial-related injury varies widely. Some sponsors provide free medical care for injuries caused by the study drug. Others do not. Get this in writing.
Your Rights as a Participant
Q19.Can I withdraw at any time? What happens to my care if I leave?
Why it matters: Participation is always voluntary. You may withdraw at any time for any reason, and your regular medical care cannot be withheld as a consequence. Confirm this explicitly.
Q20.What happens to my data if I withdraw? Will results from my participation still be used?
Why it matters: Data already collected at the time of withdrawal is typically kept for the study record. You can ask whether your data can be excluded, though this is not always possible for trials with regulatory submissions.
After the Trial Ends
Many patients focus entirely on enrollment and forget to ask what comes next. These questions matter for long-term planning.
- Will I be told my individual results? Some trials share per-patient data; others only report aggregate outcomes.
- Will I be notified of the trial's overall results? Results are typically published 1–3 years after trial completion.
- What happens to my care at the end of the trial? Especially important for effective treatments — will access continue?
- Is there a safety follow-up period? Many trials monitor participants for months or years after the active treatment phase ends.
Find trials matched to your condition
Search ClinicalTrials.gov in real time. Tidera explains each trial in plain English and generates personalized coordinator questions for your profile. Free, no account.
Search Trials Now →How to Use This List
Don't treat this as a script to read verbatim. Use it as a framework. Before your call with the research coordinator, circle the 5–8 questions most relevant to your situation and your condition. Then listen carefully — a team that answers clearly and without defensiveness is a team you can trust.
The goal isn't to find a reason to say no. It's to make sure your yes is genuinely informed.
Frequently Asked Questions
When should I ask these questions?
Before you sign the informed consent form — ideally at least a day before, so you have time to think and consult your physician. You should never feel rushed to sign.
Is it okay to ask for a second opinion before joining?
Absolutely. Discussing any clinical trial with your regular physician before enrolling is strongly encouraged. Research coordinators expect this and should support it.
What if I don't understand the answers?
Ask for clarification. Ask for written materials. Ask if there is a patient advocate or patient liaison associated with the trial. You are not obligated to understand technical terms — the research team is obligated to explain them.
Can I bring someone with me to the consent conversation?
Yes, and it's often a good idea. A family member or trusted friend can help you remember what was said, ask follow-up questions, and think through implications you might miss in the moment.
What if I have questions after I've already enrolled?
Contact your research coordinator at any time. You have the right to ask questions throughout the entire duration of the trial — enrollment does not end your right to information or to withdraw.