Why engagement remains fragile: A qualitative comparison of principal investigators’ and patient organisations’ perspectives in Italy

Background: Patient engagement and Patient Public Involvement are increasingly promoted to enhance the relevance, feasibility, and ethical grounding of clinical research, particularly in oncology, where trials can be demanding, and quality-of-life trade-offs are substantial. Despite this, engagement often remains fragile and inconsistently embedded in routine trial practices, especially where shared operational standards are limited. This study examines why engagement remains difficult to institutionalise in Italy by comparing perspectives from principal investigators and patient organisation representatives. Methods: We conducted semi-structured remote interviews with principal investigators involved in oncological clinical research and representatives of patient organisations engaged in advocacy and research-related activities. Interviews were audio-recorded with consent, transcribed verbatim, and analysed using an iterative qualitative process focused on barriers to meaningful engagement. Coding and thematic clustering were performed to identify recurring patterns and areas of convergence and divergence across the two stakeholder groups. In a subsequent interpretive step, the resulting barrier themes were organised into four cross-cutting dimensions—cultural, organisational, operational, and institutional—to support comparison and reporting. Results: Participants in both groups described a shared set of interrelated barriers but interpreted and prioritised them differently. Cultural barriers centred on tensions around expertise, authority, and the perceived legitimacy of experiential knowledge in trial design. Organisational barriers included fragmentation within the patient organisation landscape and misalignment of priorities between scientific endpoints and patient-relevant concerns. Operational barriers reflected workload pressure, limited integration of engagement into trial workflows, and asymmetries in language and expertise that constrained informed participation. Institutional barriers included discontinuity, limited feedback to patients and organisations, and the absence of clear guidance on when and how to engage patients consistently. Together, these factors contributed to engagement being late, episodic, and dependent on individual initiative rather than routine practice. Conclusions: PE and PPI in Italian oncology research remain fragile because multiple barriers intersect across culture, organisation, operations, and institutions, while stakeholders often hold different assumptions about roles and value. Strengthening engagement requires more explicit operational guidance, dedicated resources, and shared capacity-building to support earlier, more consistent, and more sustainable collaboration.