Using spatial accessibility to identify polyclinic service gaps and volume of under-served population in Singapore using Geographic Information System.

Primary care services in Singapore are provided by 18 Government-funded polyclinics and about 1200 private General Practitioners (GPs). This study aims to examine the spatial accessibility to polyclinics and identify service gaps, and suggest optimal sites using Geographic Information System (GIS) to aid in future planning. A national database containing 3.6 million polyclinic visits in 2006 were geo-analysed using ArcView GIS. Patients' travel impedance to the nearest polyclinic was computed using DriveTime to identify areas with the lowest spatial accessibility and highest volume of under-served population. Jurong West and Sembawang were ranked as top areas with poor spatial accessibility to polyclinic services. ArcGIS was used to identify optimal sites with the minimum accumulated distance impedance to this under-served population. If new facilities were set up at these identified sites, volume of visits by Jurong West and Sembawang patients who could access the nearest polyclinics within 4 km Euclidean distance from their residence would total at 123 000 and 93 000, respectively. Future efforts in polyclinic planning should take this into consideration to maximize patients' benefits and minimize patients' travelling costs in order to achieve social equity on healthcare access.