Background Despite the general supportive attitude towards advance care planning (ACP) in the community, deferring discussion remains common in real situations. Little has been known about the mechanism that constitutes the transition from attitude to the action of ACP initiation. This study aims to explore the core elements in the tripartite (patient, caregiver, and health care professional) that affect this transition.

Method Participants were recruited in trios. Patients diagnosed with life-limiting or life-threatening illness, their caregiver, and their health care worker (HCW) were recruited through purposive sampling from hospitals, aged homes, and the community centres. A semi-structured triadic interview was conducted to explore the core elements and their mechanism in affecting one’s action to initiate ACP. Data were also collected from a pre-interview questionnaire. The interviews were audio-taped. Verbatim were transcribed and coded by NVivo 1.7. Multi-perspective analysis was performed on the overlap, contrast, and inflection elements in the data.

Results Twelve triadic interviews were conducted to discuss their perception of crucial elements in the three parties which facilitate the transition to ACP initiation. Among the trios, 6 physicians, 2 nurses and 1 social worker involved, and caregivers were either spouses or children. The ‘Presence of caregiver’ and ‘familiarized personnel’ were the overlap elements shared by patient and HCW. HCW attentiveness was an element shared by patient and caregiver. Contrast elements were found in patient autonomy and family decision making, patient’s competency and presence of severe symptoms. The presence of avoiding signs of a party would inflect other parties’ action, persistence and amiable attitude can inflect other parties from reluctant to receptive to ACP.

Conclusion The study is the first of its kind, offering insights from a tripartite perspective. Specific core elements of ACP initiation were proposed for further testing of their generalizability.