If a subject is unable to read or if a legally authorized representative is unable to read, an impartial witness should be present during the entire informed consent discussion.

The impartial witness should sign and personally date the consent form after:

• the written informed consent form, and any other written information to be provided to participants, is read and explained to the participant or the participant’s legally authorized representative,
• the participant or the participant’s legally authorized representative has orally consented to the participant’s participation in the trial, and
• the participant or participant’s legally authorized representative (if capable of doing so) has signed and dated the informed consent form

By signing the consent form, the impartial witness attests that the information in the consent form and any other written information was accurately explained to the participant or the participant's legally authorized representative and that informed consent was freely given by the participant or the participant’s legally authorized representative.