Background A family-centered pediatric ACP intervention (FACE) was developed in the US, which demonstrated feasibility, acceptability and safety. The aim of this study is to evaluate the effectiveness of an ACP intervention, adapted from the FACE intervention, for pediatric oncology in Flanders, Belgium.

Methods A total of 93 dyads of parents and adolescents (age 10 – 18) receiving care in pediatric oncology wards will be recruited. Intervention dyads (N=46) will receive three weekly 60-minute sessions. Control dyads (N=46) will receive care as usual. Primary outcome is congruence in treatment preferences between adolescent and parent, measured by the Statement of Treatment Preference. Secondary outcomes are: quality of communication, decisional conflict for adolescents, and quality of life of adolescents and parents. Outcomes will be measured at baseline (T0) and 3 months after the intervention (T1). A process evaluation will be done by documentation of recruitment, analyzing audio recordings of the intervention, and post-trial qualitative interviews with adolescents (n=10) and parents (n=10) and focus groups with the involved healthcare professionals.

Discussion This will be the first pACP intervention in Europe and will provide evidence on the effectiveness of an ACP intervention in adolescents with cancer. A process evaluation will provide in-depth insight into how the pACP intervention was delivered in practice and contribute to understanding the underlying mechanisms of the intervention.