Rethinking pediatric assent: from requirement to ideal.

Physician-investigators are required to obtain informed consent from adult participants in their studies. Inclusion of children in research legally requires informed permission of a child's parent or guardian. It is increasingly recognized that a child need not assume a passive role when included in research, but that his or her active involvement should be sought, as expressed by the child's assent to partake in clinical research. This article briefly explores the history of assent and the central role of assessing a child's understanding of research and preference for participating in decisions related to their care, as necessary components of meaningful assent.