Audiovisual documentation of oral consent: a new method of informed consent for illiterate populations.

Informed consent is a legal and ethical requirement of most research in human beings, but obtaining proof of consent in illiterate populations can prove problematic. We used audiovisual documentation of oral consent (video and audiotape recording and photography), a new method of informed consent designed for illiterate populations, in the Guarani Indians Project, a genetic study in the Paraguayan Guarani Indians. We obtained consent from 42 of about 100 potential participants. We believe that our procedure allowed more than half the potential participants to exercise their freedom of refusal. We propose to include this new method as a standard procedure for clinical research in illiterate populations as an alternative to written and signed consent.