Abstract
INTRODUCTION: As global populations age at unprecedented rates, nations worldwide confront the challenge of developing effective end-of-life (EoL) care systems. While advance directives (ADs) represent a cornerstone of patient-centered dying, their adoption varies dramatically across jurisdictions. This study introduces a novel dual-dimensional analytical framework-"Resilience from Scale" and "Resilience from Structure"-to explain cross-national variations in EoL care policy effectiveness among China, South Korea, the United States, and the United Kingdom. METHODS: Using a comparative, secondary-data-based design, we apply a Most Similar Systems Design to the East Asian cases and comparative institutional analysis to the Western cases. We employ semi-quantitative, ordinal coding of "Scale" and "Structure" indicators to assess how resource capacity and institutional configurations align with divergent policy outcomes. RESULTS: The comparative evidence suggests that higher structural resilience-operationalized through national legislation, insurance integration, and state capacity/legitimacy-tends to be more consistently aligned with higher AD implementation than cultural explanations or resource availability alone. South Korea's post-2018 shift following the Life-Sustaining Treatment Decision Act provides a salient within-case contrast, supporting the comparative plausibility that institutional design can coincide with substantial changes in advance care planning uptake even where cultural constraints are often assumed to be strong. CONCLUSION: These findings challenge culturally deterministic interpretations in EoL policy research and propose a "Structural Adaptation Model" as a heuristic for jurisdictions seeking to develop effective advance care planning systems.