Do they understand? (part II): assent of children participating in clinical anesthesia and surgery research.

BACKGROUND: Participation of children in clinical research requires not only parental permission but also the assent of the child. Although there is no fixed age at which assent should be sought, investigators should obtain assent from children considered able to provide it. This study was designed to determine children's understanding of the elements of disclosure for studies in which they had assented to participate.
METHODS: The study population included 102 children aged 7-18 yr who had given their assent to participate in a clinical anesthesia or surgical study. Children were interviewed using a semistructured format to determine their understanding of eight core elements of disclosure for the study to which they had agreed to participate. Two independent assessors scored the children's levels of understanding of these elements.
RESULTS: The children's perceived level of understanding of the elements of disclosure was significantly greater than their measured understanding (7.0 +/- 2.4 vs 5.3 +/- 2.7, 0-10 scale; P< 0.0001). Complete understanding of the elements of disclosure for all children ranged from 30.4 to 89.4%. Children aged more than 11 yr had significantly greater understanding compared with younger children, particularly with respect to understanding of the study protocol, the benefits, and the freedom to withdraw.
CONCLUSIONS: Children approached for their assent to participate in a clinical anesthesia or surgery study have limited understanding of the elements of disclosure and their role as a research participant, particularly if they are aged less than 11 yr.