Background Advance/Anticipatory Care Planning (ACP) for people with terminal illnesses helps deliver personalised care, support wellbeing, and reduce healthcare crises. Patient and family acceptability/engagement, timely approaches from professionals, and sensitive communication are key. The 4ACP study evaluates integrated ACP in Scottish primary care. Four ACP steps use nationally recommended interventions; ‘AnticiPal’ primary care electronic record search (READ code-based screening), GP review (identification and assessment); ACP public information from NHS Inform (https://www.nhsinform.scot/acp) plus professional education (REDMAP framework for ACP discussions – https://ihub.scot/acp), and electronic care planning records (Key Information Summary care coordination system).

Methods A mixed-method, healthcare implementation study following StaRI guidelines implements the four ACP steps. National primary care datasets from approximately 5,800,000 GP-registered patients screened using the AnticiPal search conducted before and after ACP implementation case studies with 16 diverse GP practices in four Scottish Health Boards (study population approximately 100,000). Practice case study data include; AnticiPal screening outputs, GP ‘Thinking Aloud’ interviews of AnticiPal list assessments, patient-carer and linked GP interviews following ACP conversations, ACP plans recorded, screened cohort outcomes.

Results Approximately 0.6% of GP registered patients in Scotland who had not previously identified for palliative care screened positive for ACP. Of these, 61.6% had no Key Information Summary or documented ACP. Practices found 4ACP straightforward to implement with potential to improve ACP for significant numbers of deteriorating patients known to clinicians who had not previously been identified for ACP or palliative care. Qualitative interviews with patients, families and primary care clinicians identified areas of acceptability and concern.

Conclusions Effective ACP depends on implementation into routine practice of a feasible intervention acceptable to patients, families, and professionals alike. 4ACP provides robust implementation of national ACP programmes in Scotland and informs refinement and implementation at scale of the AnticiPal search tool and outputs for GP practices.