Based on extensive questionnaire data, this paper focuses on parents’ views about children’s right to decide about participation in research. The data originates from 4000 families participating in a longitudinal prospective screening as 1997. Although current regulations and recommendations underline that children should have influence over their participation, many parents in this study disagree. Most (66%) were positive providing information to the child about relevant aspects of the study. However, responding parents were split about whether or not children should at (...) some point be allowed decisional authority when participating in research: 41.6% of the parents reported being against or unsure. Those who responded positively believed that children should be allowed to decide about blood-sampling procedures (70%), but to a less extent about participation (48.5%), analyses of samples (19.7%) and biological bank storage (15.4%). That as many as possible should remain in the study, and that children do not have the competence to understand the consequences for research was strongly stressed by respondents who do not think children should have a right to decide. When asked what interests they consider most important in paediatric research, child autonomy and decision-making was ranked lowest. We discuss the implications of these findings. (shrink)