What should be signed and dated prior to trial participation?

• A. The informed consent form by the participant or their legally acceptable representative, and possibly by a witness and the investigator.
• B. A confidentiality agreement only.
• C. An ethics committee approval letter.
• D. The sponsor authorization letter.

Answer: (A)

The key idea is that participation in a trial can only begin after documenting informed consent. The participant or their legally acceptable representative must sign and date the informed consent form to show they understand the study and agree to participate. A witness may also sign if required by local rules to confirm the consent was given voluntarily, and the investigator signs to confirm the consent process was properly conducted. Other documents like confidentiality agreements or letters of ethics committee approval or sponsor authorization are not the same as the participant’s signed consent for trial participation.