Children’s participation in assent to paediatric oncology research: experiences of children, siblings and parents

Abstract Background Research is essential for improving outcomes in paediatric oncology, yet decisions about research participation often occur during emotionally vulnerable periods for families. Although children’s assent is ethically required, it is not always meaningfully implemented in practice. Understanding how children, siblings and parents experience the child’s involvement in the assent process, including their attitudes towards research, is crucial for promoting ethically sound research and supporting genuine child participation. The aim of this study was to describe how children with cancer, siblings and parents experience the child’s assent process during research recruitment in paediatric oncology, with particular attention to its motivational and relational dimensions. Methods A descriptive qualitative study design. Interviews were undertaken with children with cancer ( n = 11), siblings ( n = 17) and parents ( n = 9) regarding their experiences of recruitment to various types of research in Sweden. Data was analysed using reflexive thematic analysis. Results Two main themes were identified: a moral and emotional commitment to research , and relational assent—trust, loyalty and parental mediation. Children, siblings and parents described research participation as meaningful and morally significant in a vulnerable situation. Children’s involvement in assent ranged from active participation to limited influence, with some decisions made primarily by parents. Decisions about research participation were shaped by relational dynamics, in which trust, loyalty, and emotional vulnerability and parental mediation played central roles. Conclusions Families are strongly motivated to contribute to research in paediatric oncology. However, sustaining trust and safeguarding research integrity require consistent and meaningful implementation of children’s assent. Child-centred, flexible, and context-sensitive assent processes are key, alongside ethical awareness of how relational dynamics shape children’s autonomy. Recognising parents as key partners is essential for upholding both ethical standards and children’s rights in paediatric research.