A participant who cannot read or write can still give valid consent when an impartial witness is present. Capture supports an optional witness co-signature in the eConsent workflow, between the participant’s signature and the investigator’s countersignature.
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Form read aloud to the participant
Witness present for the whole discussion
Participant gives consent and signs
On-screen signature, email one-time code
Witness co-signs
Added to the signature record
Investigator countersigns
Password re-authentication, meaning statement
Fully Executed
PDF with signatures and audit trail
Witness signatures in brief
Optional
witness co-signature in the signing workflow
Hashed
every signature linked to the exact document text
export with signature data, timestamps and audit trail
Free
sandbox to rehearse a witnessed consent, no time limit
The rules
Three frameworks mention witnesses, and they are not the same. ICH E6 (GCP) defines the impartial witness as a person independent of the trial who cannot be unfairly influenced by people involved with it, who attends the consent process if the subject or the legally acceptable representative cannot read, and who reads the consent form and other written information. Section 4.8.9 asks for the witness to be present during the entire consent discussion. After the participant has orally agreed and signed, the witness signs and dates the form, which is commonly worded as attesting that the information was accurately explained, apparently understood and freely agreed.
The EU Clinical Trials Regulation (Regulation 536/2014, Article 29) requires consent to be written, dated and signed. Where the subject cannot write, consent may be given and recorded by appropriate alternative means in the presence of at least one impartial witness, who signs and dates the document. In the US, 21 CFR 50.27(b)(2) allows a short form method: a short written document says the elements of consent were presented orally, the participant signs the short form, a witness to the oral presentation signs both the short form and the written summary, and the person obtaining consent signs the summary. The IRB must approve the summary.
Two points trip teams up. First, the witness has to be present for the discussion itself, not only for the signature. A name added afterwards is not witnessing. Second, a witness in the ordinary sense, someone who watches a person sign, is not the same as the impartial witness of ICH E6. Some institutions also ask for a witness on every consent for local reasons, which is a different requirement. Your IRB or ethics committee decides which applies, which is why this page stays at the level of how the software supports the process. See the glossary entry on IRBs and good clinical practice for context.
Side by side
| Framework | Trigger | Witness does | Who signs |
|---|---|---|---|
| ICH E6 4.8.9 | Subject or representative cannot read | Attends the whole discussion, hears the form read, attests accuracy and free consent | Subject or representative, witness, person conducting the discussion |
| EU CTR Article 29 | Subject cannot write | Is present when consent is given by alternative means, signs and dates | Person conducting the interview, witness, and the subject or representative where able |
| 21 CFR 50.27(b)(2) short form | Short form method chosen and IRB approved | Witnesses the oral presentation, signs short form and summary | Subject on short form, witness on both, person obtaining consent on the summary |
| Local institutional rule | Site policy, for example every consent | Confirms the signature was made by the participant | Per the institution |
A summary of general rules, not legal advice. National law, IRB policy and the protocol can add or change requirements.
In Capture
Capture’s eConsent signature workflow is participant signature, optional witness co-signature, then investigator countersignature. The document becomes Fully Executed only once the required parties have signed. Each signature is hashed to the exact text signed, so a later change to the consent document is detectable.
Participant signature
Signed and email one-time code verified
Witness co-signature
Added to the signature record
Investigator countersignature
Awaiting review
Document hash
Linked to the exact text signed
Build a consent form, run the participant, witness and investigator steps, and review the signed PDF in the free sandbox.
Practical points
The witness requirement is about presence, so the hardest question for electronic consent is where the witness is. If the participant is at the site with the study nurse and an independent witness beside them, the participant signs on the site’s device or their own, and the witness co-signs in the same session. If the consent is taken remotely, ethics committees differ on whether a witness joining by phone or video call is enough. Capture does not provide video consent, so agree the arrangement with your ethics committee first and describe it in the consent SOP.
A participant who cannot read can usually still understand a form that is read aloud, and may be able to sign or mark. A participant who cannot write at all poses a different question: how the agreement is recorded in the electronic record, and what the witness adds to it. Agree the wording of the witness attestation and the source note with your IRB, and keep the note in the investigator site file, since the electronic form records signatures and times but not what happened in the room.
Do not use the witness as a substitute for the participant’s own understanding. If a participant cannot follow the information even when read aloud, the question is capacity, and the route is the legally authorized representative workflow. The two can apply together: a LAR who cannot read can consent in the presence of an impartial witness. For the broader picture of consent software, see eConsent software for clinical trials.
Audit readiness
Source note: participant could not read or write, or the short form method was approved.
Name, relationship to the participant and confirmation of no role in the trial, per SOP.
Note by the person conducting the discussion that the witness attended throughout.
Participant first, witness after the participant has agreed, countersignature last; timestamps in the audit trail.
Document hash linking every signature to the consent text.
Signed PDF given to the participant, hand-over noted in source.
A person who is independent of the trial, cannot be unfairly influenced by people involved in it, and attends the consent process when the participant or their representative cannot read. They hear the information read, and later attest that it was accurately explained and consent was freely given.
Yes. eConsent has an optional witness co-signature in the signing workflow, between the participant’s signature and the investigator’s countersignature. It is recorded in the signature record and the audit trail.
No. ICH E6 asks for one when the participant or representative cannot read, the EU CTR when a subject cannot write and consents by alternative means, and 21 CFR 50.27(b)(2) for the short form method. Some institutions require one for local reasons. That is why it is optional in Capture.
Usually an adult with no role in the trial. Whether a relative or a member of site staff outside the study team is acceptable depends on the ethics committee and the site SOP. The investigator and study team members should not be the witness unless explicitly accepted.
It depends on the rules you work under. The witness must be present for the whole discussion, and ethics committees differ on remote presence. Capture does not provide video consent, so agree the arrangement in advance.
Every signature is cryptographically linked (hashed) to the exact document content at signing time, so a change to the document changes the hash. All signature events are in the audit trail, which cannot be modified through the interface.
Yes. The signed consent exports as a PDF with embedded signature data, timestamps and the audit trail.
Yes. The free sandbox includes eConsent with the full signing workflow. There is no credit card and no time limit.
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