Co-designing a family-centered intervention to support home-based caregiving in advanced chronic illness: A double diamond framework-guided process.

BACKGROUND: Family caregivers of people living with advanced chronic illness experience sustained emotional, physical, and social challenges. However, existing support interventions remain fragmented, frequently individualized, and insufficiently grounded in families' lived experiences. Many focus on a single "primary caregiver," overlooking the relational, dynamic, and shared nature of caregiving within families. Participatory design approaches may help address these gaps, yet structured design thinking frameworks remain underexplored in health research, particularly in family caregiving and primary care contexts.

AIM: To describe the application of the Double Diamond (DD) framework to the development of HELP-F, a Home-based pErson-centered care to Listen and suPport Family caregiving in advanced chronic illness.

METHODS: A participatory co-design study was conducted following the four phases of the Double Diamond model. The Discover phase involved narrative family and individual interviews with 24 family caregivers providing home-based care to a relative with advanced chronic illness, analyzed using an inductive narrative approach. The Define phase integrated qualitative findings with evidence from a systematic review of home-based caregiver interventions to develop a preliminary logic model grounded in the Gothenburg Centre for Person-Centered Care framework. In the Develop phase, the logic model was refined through its presentation across nine primary care centers and a focus group involving primary care professionals, family representatives, and researchers with recognized expertise in the field. The Deliver phase comprises an ongoing pilot implementation across eight primary care centers to assess feasibility and acceptability. Data were analyzed iteratively to inform each subsequent phase.

FINDINGS: The process generated a nurse-led intervention structured around four core elements: eliciting family caregiving narratives, co-creating an individualized family care plan, providing longitudinal follow-up, and integrating support within routine primary care. Three design priorities informed the intervention: recognizing the family as the unit of care, strengthening caregivers' preparedness and emotional support, and enabling flexible delivery according to family context. Family caregiver representation was more limited in some later co-design phases, and the pilot phase is ongoing; therefore, effectiveness outcomes are not yet available.

CONCLUSIONS: This study demonstrates the value of applying a structured design thinking framework to the development of family-centered interventions in primary care. The Double Diamond model offers a transparent and flexible methodological pathway to address the complexity of family caregiving, supporting the co-creation of contextually relevant, practice-oriented interventions. The findings contribute to methodological debates on co-design in health research and support a shift towards family-oriented, primary care-based approaches in advanced chronic illness.

REGISTRATION: NCT07184216; ClinicalTrials.gov.