Timely short-term specialized palliative care service intervention for older people with frailty and their family carers in primary care:Development and modelling of the frailty+ intervention using theory of change

Background: Palliative care is advocated for older people with frailty and multimorbidity in the community. However, how to best deliver it is unclear. Aim: To develop and model an intervention of short-term specialized palliative care that is initiated timely based on complex care needs and integrated with primary care for older people with frailty and their family, detailing the intervention components, outcomes and preconditions needed for implementation, using a novel theoretical approach. Design: Observational study informed by the UK MRC guidance for complex interventions integrated with a Theory of Change (i.e. hypothetical causal pathway to impact) approach. We synthesized evidence from a systematic review, semi-structured interviews, group discussions and Theory of Change workshops. Setting: Primary care in Flanders, Belgium. Results: We identified patient and family carer-related long-term outcomes and preconditions to achieve them for example, service providers are willing and able to deliver the intervention. The intervention components included implementation components, for example, training for service providers, and a core component, that is, provision of timely short-term specialized palliative care by a specialized palliative home care nurse. The latter includes: short-term service delivery; collaborative and integrative working within primary care; delivery of holistic needs- and capacity-based care; person-centred and family-focussed; and goal-oriented pro-active care. Conclusions: The Theory of Change approach allowed us to identify multiple intervention components targeting different stakeholders to achieve the desired outcomes. It also facilitated a detailed description of the intervention which aims to increase replicability and effective comparisons with other interventions.