GIS-Based Screening of Spatial Mismatch Between Primary Health Care Facility Locations and Population Need in Macao: Cross-Sectional Ecological Study (Preprint)

BACKGROUND Equitable allocation of primary health care (PHC) facilities is essential for urban health planning. Conventional accessibility assessments may overlook mismatches between facility distribution and population needs, particularly among older adults. Objective: To develop a reproducible geographic information system (GIS)–based framework for assessing PHC facility-location equity using total population and older-adult population benchmarks in Macao. OBJECTIVE To develop a reproducible geographic information system (GIS)–based framework for assessing PHC facility-location equity using total population and older-adult population benchmarks in Macao. METHODS This cross-sectional ecological study analyzed 2021 population, PHC facility-location, and outpatient service data across 23 statistical zones. Population-demand shares were compared with facility-location shares to identify allocation gaps. A demand–supply matrix identified high-need zones without facilities. Outpatient volumes provided supplementary context. RESULTS The 2021 analysis covered 681,293 residents, including an estimated 82,741 adults aged 65 years or older, and 10 PHC facilities. Hac Sa Van e Iao Hon exhibited the largest allocation deficits under both benchmarks (−10.11 and −10.16 percentage points). Five zones met the high-need/no-facility criterion: Hac Sa Van e Iao Hon, San Kio, Toi San, Horta e Costa e Ouvidor Arriaga, and Zona Central. Gap direction differed between benchmarks in two zones. Outpatient volumes varied across facility locations but did not reveal patients’ residential origins. CONCLUSIONS GIS-based population–facility comparisons can identify zones requiring further PHC planning assessment but cannot establish actual service shortages or unmet needs. Future analyses should incorporate updated demographic data, travel networks, facility capacity, and cross-district utilization.