Understanding multilevel influences on the adaptation of a complex intervention for oncology to palliative care transitions : a qualitative study across seven European countries

Adapting complex healthcare interventions for use across diverse healthcare systems requires balancing fidelity to core components with responsiveness to local contexts. The Pal-Cycles project aims to support transitions in care for patients with advanced cancer across seven European countries. Understanding the multilevel factors that influence adaptation is essential to ensure contextual fit while maintaining intervention integrity.To explore the multilevel factors that influenced the adaptation of the Pal-Cycles intervention across seven European countries.A qualitative study was conducted with purposively sampled country lead team members from all participating countries. Data were derived from focus groups, in which participants reflected on and discussed their experiences of cross-country adaptation meetings, and were analysed using framework analysis.Fourteen country lead team members participated in the study. Analysis identified five areas reflecting multilevel factors that influenced the adaptation of the Pal-Cycles intervention: (1) Organisational variability as a barrier to adapting the Pal-Cycles intervention, (2) Disparities in training and shared motivation to improve palliative care communication, (3) Multidisciplinary collaboration shaped by organisational and cultural contexts, (4) Balancing optimism and practical constraints: stakeholder views on the Pal-Cycles intervention, (5) Working together to adapt the Pal-Cycles intervention across cultures. Organisational variability influenced service availability, integration between oncology and palliative care, and communication pathways. Disparities in previous training and shared motivation shaped clinicians' engagement with the intervention's training component. Multidisciplinary collaboration varied across settings, affecting role clarity and coordination among healthcare professionals. Stakeholder perspectives, including those of cancer clinicians, general practitioners, and consortium members, informed decisions about which elements of the intervention were most relevant in each context. Finally, working together to adapt the intervention across diverse cultural and organisational settings involved iterative discussions that balanced flexibility with preservation of the intervention's core components.The adaptation of Pal-Cycles was shaped by interrelated organisational, professional, and cultural factors. Recognising how local contexts influence the prioritisation and operationalisation of intervention components is essential for achieving a balance between standardisation and flexibility in cross-national healthcare interventions.