Systemic Health System Population Segmentation: Development and Evaluation of Systemic Needs-Based Population Segmentation Models in a Regional Population Health System in Singapore Based on the Unified Care Model

Context: Population segmentation is a critical health system planning activity that enables more integrated, needs-responsive and sustainable care. This paper describes the development and evaluation of a person-centred and needs-based Systemic Health System Population Segmentation Model by Yishun Health, a regional population health system in Singapore. Methods: Three interdependent models were developed: Lifelong Care Segmentation Model, Needs-Based Sub-Segmentation Model, and Episodic Care Segmentation Model, all underpinned by the Unified Care Model. These models systematically stratify residents into mutually exclusive and collectively exhaustive population groups based on biopsychosocial needs across different health system levels. An expert-driven design process was used, supported by integrated administrative and clinical data. Model evaluation examined the ability to stratify patients into distinct risk-groups using healthcare utilisation, costs, and readmission outcomes. Findings: In 2022, 78,810 residents were segmented into seven Lifelong Care segments, with 43,473 residents with chronic conditions further stratified into sub-segments reflecting varying complexity and psychosocial needs. Additionally, 14,335 emergency admissions were categorised into six Episodic Care segments. Healthcare utilization and annual healthcare costs differed significantly across needs-based sub-segments (p< 0.001). Higher episodic care needs were associated with longer hospital stays, higher rates of emergency readmissions, and admission costs (p< 0.001). Psychosocial issues emerged as a key determinant of poorer outcomes across segments. Conclusions: Our Systemic Health System Population Segmentation Models provided a robust framework for health systems governance and leadership system redesign. i.e., aligning service planning, care integration, and accountability with the differentiated needs of population groups. By operationalising systemic, person-centred segmentation, the models supported more effective and accountable service delivery, resource allocation, and outcome tracking at both regional and hospital system levels—forming foundational enablers of population health system transformation.