Comparing Three GIS Techniques for Modelling Geographical Access to General Practitioners

Accessibility to health services is a social and economic issue that has many dimensions. This article compares three techniques for measuring geographical accessibility to general practitioners (family doctors). These techniques can be described as ratio, least-cost path, and allocation methods. The ratio method is the most common and simply measures the population-to-GP ratio for a given area. The least-cost path and allocation techniques rely on GIS network analysis and provide information on travel times and distances. The allocation analysis differs from least-cost path analyses because it considers the number of GPs available and this acts as a capacity constraint. The use of GIS network analysis can produce a number of different statistics on accessibility that can be visualized as a map. This article will argue that the use of a capacity constraint is important and that the population further than 30 minutes from a GP is an effective statistic for comparing the accessibility of different managemen...