3.2 Secondary Cohort and Administrative Data Architecture
This study establishes a dual-layered methodological architecture to evaluate the structural effects of regional healthcare centralization across Finnish welfare boundaries. The qualitative dimension adopts systematic policy process tracing to investigate institutional governance transitions and previous reform dynamics, addressing historical structural shifts where organising responsibilities moved from municipal authorities to larger regional bodies ("Why did Social and Healthcare Services Reform Fail in Finland?", 2020). Complementing this institutional analysis, the quantitative framework utilizes a retrospective nationwide registry-based design to measure specialist care access and acute secondary care trajectory shifts. Administrative health registers maintained by the Finnish Institute for Health and Welfare provide comprehensive decedent cohorts, such as populations diagnosed with lung cancer and nonmalignant pulmonary disease, to track longitudinal patient encounters across specialized service tiers ("Specialist Palliative Care Reduces the Need for Acute Health Care Services", 2025). Specifically, the secondary data architecture captures time-stamped hospital admissions, emergency department contacts, and specialist palliative care episodes across regional boundaries. Multivariable regression protocols evaluate whether early specialist consultation mitigates acute hospitalizations and secondary care utilization, isolating regional institutional factors from underlying clinical disease trajectories. Integrating longitudinal administrative microdata with structural governance frameworks enables this methodology to control for pre-existing regional variations while assessing the empirical efficacy of service integration mechanisms across secondary sectors. Ultimately, this mixed-methods approach ensures rigorous construct validity when modeling the dynamic interface between welfare governance restructuring and specialized healthcare access.