Influence of pediatric advance care planning on the secondary outcomes of the BOOST pACP trial: determinants of communication between parents and adolescents with cancer

This study explores the impact of a pediatric advance care planning program (BOOST pACP) on adolescents with cancer and their parents, focusing on behavioral determinants such as attitudes, self-efficacy, intention, and behavior regarding the discussion of ACP topics. A multi-center, parallel-group superiority trial was conducted with adolescent-parent dyads recruited from four pediatric oncology wards in Belgium. The intervention group received four structured ACP sessions facilitated by an external professional, while the control group received care as usual. The acquired insights were shared with their oncologist. The behavioral determinants were measured through self-developed questionnaires based on the Theory of Planned Behavior (TPB) at baseline (T0), 3 months (T1), and 7 months (T2). This secondary data analysis used exploratory factor analysis and linear mixed models to assess the impact of the intervention. Forty-nine families were enrolled and randomized to the BOOST pACP group (n=24) or care-as-usual (n=25). At T1, fathers in the intervention group had significantly lower negative attitudes towards discussing ACP topics than their counterparts in the control group; mothers in the intervention group had increased intentions to discuss end-of-life care topics; and adolescents had reduced intentions to discuss ACP topics with their oncologist. No significant differences between intervention and control were observed in self-efficacy and mothers’ attitudes. Conclusion: Our RCT suggests a limited effectiveness of a pediatric ACP intervention in changing behavioral determinants associated with ACP communication. As the study was eventually underpowered, these findings underscore the need for a better understanding of the mechanisms driving or hindering outcomes and impact of pediatric ACP and highlight the complexity of influencing ACP behaviors within the pediatric oncology setting. Trial registration: ISRCTN, number 33228289 10.1186/ISRCTN33228289. Registration date: 22/01/2021. (Table presented.)