Informed Consent

Mid-infusion, two weeks into a randomised trial, a participant mentions to her coordinator how glad she is to be getting the new drug. Nobody promised her that — no one could have — and her file holds a signed, dated, witnessed consent form saying she understood she would be assigned to an arm at random. On paper, her consent is perfect. In the room, it never happened.

That gap — between the paperwork and the decision it was supposed to record — is what this module is about. Informed consent is not the four minutes it takes to sign a form. It is a process: a conversation that has to actually work, repeated and updated for as long as someone stays in your trial, and adapted without shortcuts for the people who cannot have that conversation in the ordinary way at all.

Learning Objectives

After this module, you can:

• Apply the three-part test for valid consent, and know who is allowed to run the consent process
• Assemble a compliant consent process — what must be disclosed, in what form, and how it is documented
• Apply the incentive rules and spot undue influence before it compromises a decision
• Decide when re-consent is required, and act on it
• Apply the consent rules for people who cannot consent for themselves, and for emergency and deferred situations

Here is the shape of what follows. The first three sections build the ordinary case — what makes consent valid, what has to be disclosed, and how you prove it happened. The next two cover the forces that can quietly undo a compliant process — money and power, and information that goes stale. The last two cover where the ordinary process doesn't fit at all: someone who cannot consent for themselves, and situations with no time to ask anyone anything.

The Three-Part Test: Why a Signature Isn't Consent

Ask most site teams what "valid consent" means and they will describe a document: signed, dated, witnessed where required, filed. Ask an ethics committee, and the document is the least interesting part of the answer.

Informed consent is valid only when three things are all true at once: the person received adequate information, they understood it, and their decision was voluntary. Miss any one of the three and the signature is worthless, however clean the paperwork looks. The coordinator in the opening scenario had a form that satisfied every box — and consent that had failed on comprehension.

Swiss law makes this a hard requirement, not a best-practice aspiration. Consent must be given in writing, and the persons concerned must receive comprehensible oral and written information — not one or the other — before deciding. HRA They must also be given an appropriate period for reflection before that decision is made. HRA ICH E6(R3) adds the operational instruction behind "comprehensible": the investigator or delegated site staff must give the participant ample time and opportunity to ask questions, and those questions must be answered to the participant's actual satisfaction — not just addressed. ICH E6(R3)

Timing follows directly from this. No study-specific procedure — including a screening assessment that goes beyond routine clinical care — may happen before consent is obtained and documented. A blood draw taken "just to check eligibility" before the form is signed is not a shortcut; it is a procedure performed on someone who has not yet agreed to be in your study.

Who is allowed to have this conversation is not open-ended either. The consent discussion must be conducted by the investigator or by site staff the investigator has specifically delegated for this task, in line with the applicable regulatory requirements — not by whoever happens to be free. ICH E6(R3) That is a narrower question than who is on the trial team, which is Module 3's territory. Here the question is: within that team, who has actually been named and trained to run this specific conversation, and can the delegation log show it? Where the participant cannot give consent themselves — a minor, an adult who has lost capacity — a legally acceptable representative gives it on their behalf; that entire mechanism has its own section near the end of the module, not this one.

Tuskegee (Module 2 tells the full story) is the reason this module exists at all: the investigators there did not obtain flawed consent, they obtained none, by lying to participants about what was actually being done to them. Deception and a genuine but poorly-run conversation are different failures, but they land in the same place — a person who never actually agreed to what happened to them.

What the Participant Must Actually Understand

An ethics committee reviewing a new participant information sheet (PIS) — the document that carries this disclosure, alongside the consent form itself — rarely rejects it for saying too little. Almost as often, it rejects one for saying too much: sixteen pages of dense text that satisfies every checklist item and leaves the reader no wiser than when they started. Disclosure and understanding are not the same target, and chasing only the first one can defeat the second.

The list of what the PIS must disclose is genuinely long, because Swiss law and ICH-GCP both build it from real experience of what participants later say they wished they'd known. It groups into five clusters:

• What the study actually is and does — that it is research and participation is voluntary; its purpose, nature and expected duration; the procedures involved, including any invasive ones and the probability of random assignment to a given arm; what alternatives exist if the person doesn't join.
• The risk–benefit picture — foreseeable risks and burdens; the benefits reasonably expected, and an explicit statement if there is no intended clinical benefit at all; compensation or treatment available for trial-related injury.
• Rights and choices — that participation is voluntary and can be withdrawn at any time without penalty or effect on their medical care; the right to ask further questions at any time; the right to be told about incidental ("surplus") findings, and the right to choose not to know; the right to receive the study's results and their own actual treatment assignment when available.
• Money and practicalities — the sponsor and main funding sources; any expenses or prorated compensation for participation; the approximate number of participants and expected duration; the circumstances under which their participation could be stopped.
• What happens to their data — the personal-data protection measures in place; that the sponsor's and authorities' representatives may access source records to verify the trial, with confidentiality otherwise maintained; that the trial will be registered and a public summary of results eventually published. HRA KlinV ICH E6(R3)

That is a lot of ground — which is exactly why how you deliver it matters as much as what's in it.

Wording and format are a legal requirement, not a style preference. The information has to be as clear and concise as the content allows, in plain language, without unnecessary volume or complexity — the test is genuine understanding, not technical completeness. ICH E6(R3) ICH E6(R3) explicitly opens the door to formats beyond a printed sheet: text, images, video, and other interactive methods may all be used, and should be chosen with the trial population in mind — a population unfamiliar with computerised systems should still be offered a paper-based route. ICH E6(R3) Choosing a format is not decoration; it is part of discharging the comprehension requirement from the three-part test.

There is one narrow case where you may tell participants less than everything. Some studies break if people know exactly what is being watched — tell them you are measuring how honestly they fill in a symptom diary, and the diary changes. For precisely this problem, Swiss law permits incomplete information before a study begins, on two conditions that must both hold: withholding that specific detail is methodologically essential, and the project carries no more than minimal risks and burdens. And the debt comes due: participants must be told the whole story as soon as possible, and until they have been — and have then said yes — nothing collected in the meantime may be used for the study. HRA

After the Trial: Post-Trial Access

The participant information sheet's rights run mostly to the trial's edge — voluntary participation, withdrawal at any time, the results when they come. One duty reaches past that edge, to what a participant is owed once the trial is over.

If the trial identifies an intervention as beneficial and reasonably safe for the people in it, participants who still need it should not lose access the day the study closes. The Declaration of Helsinki makes this a provision arranged in advance: before the trial begins, sponsors and researchers must arrange post-trial access — provided by themselves, by healthcare systems, or by governments — for all participants who still need an intervention the trial found beneficial and reasonably safe. It is planned before the first participant enrols, not negotiated at close-out, and any exception must be approved by the ethics committee rather than decided by the sponsor alone.

For the consent process the consequence is concrete: those provisions are themselves a required disclosure. What post-trial access a participant can expect must be explained as part of informed consent, alongside the forward-looking rights the sheet already carries — so that someone deciding whether to join knows not only what the trial asks of them, but what they can rely on afterward if the intervention works for them. Declaration of Helsinki

Proving It Happened: Documentation, Witnesses, Electronic Consent

An inspector does not ask whether the consent conversation happened. They ask you to show them it happened — and "I'm sure it did" is not evidence.

The signed, dated consent form is the anchor, but it is not the whole record. By signing it, the investigator or delegated site staff attest that consent was freely given and that the information was accurately explained to, and apparently understood by, the participant — the signature is a statement about the process, not only a receipt of the participant's agreement. ICH E6(R3)

Two situations require an extra signature. If the participant cannot read, an impartial witness — someone with no role on the trial team — must be present for the entire discussion; once the information has been read and explained and the participant has given oral consent, the witness signs, attesting that the information was accurately conveyed and the consent freely given. ICH E6(R3) If the participant doesn't speak the language of the consent materials, Swiss law allows the written-form requirement to be waived where translation would demand disproportionate effort, provided an independent, qualified translator gives the information orally and confirms this in writing. KlinV Neither exception is a workaround — both exist precisely because the three-part test's comprehension requirement doesn't disappear when reading or language is the barrier.

Electronic and remote consent are permitted, on conditions. ICH E6(R3) allows computerised systems and remote consent processes, provided a paper-based alternative remains available to anyone who wants it, and the investigator confirms the participant's identity whichever way the discussion is conducted. ICH E6(R3) Swiss law sets the technical bar for the electronic route specifically: the method must unambiguously identify the person consenting, be designed to prevent a rushed decision, and be protected against later modification — and how each of those is achieved has to be described in the trial's application dossier. KlinV An electronic signature is not a lesser form of consent; it is consent that has to clear a specific, documented technical bar instead of a paper one.

Beyond the form itself, three more things belong in the record:

• The discussion itself — a note in the medical record or study file that the conversation took place, who was present, and that questions were answered — not just that the form exists.
• The version in force — participants must consent to the specific PIS and consent-form version the ethics committee has currently approved. Signing an outdated version, even one that was compliant when superseded, is a GCP deviation.
• Withdrawal — documented with the date and, if the participant offers one, their stated reason. Withdrawing consent has a concrete data consequence: once the data already collected has been evaluated, the participant's biological material and personal data must be anonymised — unless the participant explicitly waives that right when withdrawing, or was told at enrolment that anonymisation wouldn't be possible and consented on that basis. KlinV

Payment, Power, and the Limits on Voluntariness

A cardiologist who is also a trial investigator mentions to her own patients that a new drug "looks very promising," then asks if they'd like to join her study. Nobody threatened anyone. That is exactly the problem — the pressure here doesn't need a threat to work.

The three-part test named voluntariness as one of the required elements of valid consent. Two forces most often undermine it without anyone intending harm: money, and the relationships in the room.

On money, Swiss law is stricter than most people expect. Where a research project has an expected direct benefit to the participant, no one may receive payment or any other non-cash advantage for participating — not a small one, not a large one, none at all. Where a project has no expected direct benefit, appropriate remuneration is permitted, and the appropriateness of the amount is one of the things the ethics committee explicitly reviews. HRA KlinV That is a bright line, not a proportionality test: the question for a direct-benefit study is never "is the payment reasonable?" — it's "is there a payment at all?"

On power, the recurring patterns are:

• Dual roles — when the investigator is also the participant's treating clinician, the participant may feel unable to decline without jeopardising their care. Neither the investigator nor site staff may coerce or unduly influence a participant to join or continue. ICH E6(R3) Where the potential participant is in a dependent relationship with the person seeking consent, or could reasonably feel unable to refuse, someone independent of that relationship must be the one to seek consent instead. Declaration of Helsinki
• Dependency — prisoners, employees of the institution running the study, students of an instructor who is also the investigator, and residents of care facilities can all feel pressure to agree that has nothing to do with the study's merits.
• Therapeutic misconception — patients, especially, tend to read "research participation" as "personalised treatment." The participant in this module's opening scene, glad to be "getting the new drug" she was in fact randomised to receive or not, is this misconception in action. The no-intended-benefit disclosure from the PIS content list exists specifically to correct it; describing an unproven drug as "very promising" undercuts that disclosure even if it's technically true.

When Consent Runs Out: Re-Consent Triggers

A protocol amendment lands in the sponsor's portal on a Tuesday, adding an extra imaging visit and naming a newly identified drug interaction. Everyone currently enrolled consented to the trial as it existed before that email arrived. Their consent, as things stand, is now out of date — and nobody has told them.

Consent is not a single event you complete once and file away. When new information emerges that could plausibly change a participant's willingness to continue — a new safety signal, a substantial protocol amendment that adds procedures or risk — the investigator must assess whether re-consent is needed, considering the trial's stage and whether the new information affects only future enrolees or everyone already in the study. ICH E6(R3) Not every change clears this bar: a purely administrative amendment with no bearing on risk, burden, or the participant's decision doesn't trigger it. What does is anything that could plausibly change the answer to "would I still say yes?"

Where re-consent is needed, the mechanism is exact: the new information is clearly identified in revised consent materials, those materials receive the ethics committee's approval before use, and the re-consent conversation is documented separately from the participant's original consent — using the same "prove it happened" documentation standard as the original, not a lesser one. ICH E6(R3)

Consent for Someone Who Can't Give It: Capacity, Representatives, Assent

A participant who signed a dementia trial's consent form at baseline eighteen months ago can no longer follow the study visit's questions today. Nobody revoked anything. The person who agreed to this trial, in the sense that matters, is not entirely the person sitting in the room now — and someone still has to decide, correctly, who speaks for her from here.

Capacity, in this sense, is not a label like "a minor" or "has dementia." It is the ability, for this specific decision, to understand the relevant information, weigh the risks and benefits, and communicate a choice. A person can lack capacity for one decision and retain it for another; capacity is assessed against the decision in front of them, not assigned once for life.

Module 6 covers why this population gets extra protection at all — the subsidiarity principle, and the ethical case for protecting rather than excluding. Here is how that protection actually works when someone is in front of you.

The starting principle applies to everyone who might lack capacity, regardless of why: children, adolescents, and adults lacking capacity must be involved in the consent procedure as far as they are able, and increasing weight must be given to their own views the older and more mature they are. HRA That involvement is not a courtesy.

Swiss law sets tiered conditions by population and by whether the research offers the person any direct benefit: HRA

Who actually signs, in order, is: a prior directive the person gave while still capable, if one exists; failing that, their legal representative, a designated trusted person, or the next of kin. HRA Whichever of these applies, the person's own visible opposition — not just a formal refusal, but resistance shown through behaviour — is never overridden by someone else's signature.

This is also where assent operates, and it is not the same thing as the representative's consent. A minor who can form and express a view gets age-appropriate information and is asked for their own agreement — in addition to, never instead of, the legal representative's consent. The same logic extends to anyone who cannot give full legal consent but can meaningfully engage with the decision. ICH E6(R3) Assent is an affirmative agreement — silence or the absence of an objection is not assent. ICH E6(R3) Where the participant is capable of doing so, they should sign and date the assent form or the consent form itself, alongside the representative. ICH E6(R3)

A trial that enrols minors also has to plan for a moment many protocols miss: a participant who reaches the legal age of consent partway through the trial. ICH E6(R3) requires a process to be considered for exactly this — obtaining the participant's own consent as an adult, in their own right, rather than continuing indefinitely on a representative's original signature. ICH E6(R3) This is a fresh consent event, run on the same documentation standard as any other re-consent — not a new rule, just this section's trigger for it.

Emergency and Deferred Consent

A patient arrives in cardiac arrest. There is a trial actively recruiting exactly this presentation, and the intervention window is minutes. There is no representative in the room, no time to find one, and the patient obviously cannot answer any questions. If research can happen here at all, it cannot start with a conversation.

Swiss law allows it — carefully. Three things stand in for the conversation that cannot happen. Someone must be actively working to establish what this person would want, as soon as that becomes possible. The person must not be visibly resisting the intervention — unconscious is not the same as willing. And a physician with no part in the research must be brought in to look after the person's interests before enrolment — or, exceptionally and for good reason, as soon as possible after. HRA If the project offers the person no direct benefit, the familiar bar from the capacity section rises on top of all this: minimal risk and burden only, and substantial expected findings for others in the same situation. HRA The Declaration of Helsinki runs on the same logic, and adds a test worth keeping in your head: the very condition that stops this patient from consenting must be the thing the study exists to investigate. An emergency is never a recruitment convenience — only research into unconsciousness gets to enrol the unconscious. Beyond that, the research must genuinely be unable to wait, no representative is reachable, the ethics committee approved the approach in advance, and the protocol states the specific reasons. Declaration of Helsinki

None of this replaces consent — it defers it. As soon as it becomes possible, the person must be informed about the project and may then give or withhold post hoc consent; if they withhold it, their data and biological material may no longer be used for the research. HRA For clinical trials, Swiss law turns that principle into a procedure — one the protocol must spell out in advance, not improvise on the day. The sponsor and investigator must make sure post hoc consent is sought as soon as possible: from the participant themselves, or, where the participant is a child, an adolescent, or an adult permanently lacking capacity, from their legal representative. KlinV If the participant dies before consent or refusal was obtained, the material and data may only be used for research if the person had, in an advance directive or otherwise, consented to that use; absent such a statement, the next of kin or a designated trusted person may consent instead. KlinV

Handling the material collected before consent exists is itself tightly bounded. It may only be evaluated once consent has actually been obtained — except, narrowly, where the material can only be used within a limited window, or evaluation is necessary for the participant's own safety. KlinV If post hoc consent is refused, the material and data must be destroyed. If destroying them would compromise the trial's validity in an essential way, their use is still permitted despite the refusal — but only once anonymised without delay, and the person's right to object is preserved regardless. Any scenario where this exception might apply has to be anticipated and stated in the protocol in advance, not improvised afterward. KlinV

Module Summary

The signed form is the record. The conversation before it — repeated whenever something changes, adapted without cutting corners for the person who cannot have it in the ordinary way — is the actual safeguard. One can be perfect while the other has failed, and only one of those failures shows up in a chart audit.

You can now:

• Apply the three-part test for valid consent, and know who is allowed to run the consent process.
• Assemble a compliant consent process — what has to be disclosed, in what form, and how it is documented, on paper or electronically.
• Apply the incentive rules and spot undue influence before it compromises a decision.
• Decide when re-consent is required, and run it to the same documentation standard as the original.
• Apply the consent rules for people who cannot consent for themselves, and for emergency and deferred situations — including the one rule that overrides every tier: a participant's own visible refusal wins.