Bell Scott, Wilson Kathi, Shah Tayyab Ikram, Gersher Sarina, Elliott Tina
Department of Geography and Planning, University of Saskatchewan Saskatoon, Canada.
Spat Spatiotemporal Epidemiol. 2012 Apr;3(1):17-29. doi: 10.1016/j.sste.2012.02.003. Epub 2012 Feb 23.
Accessibility to health services at the local or community level is an effective approach to measuring health care delivery in various constituencies in Canada and the United States. GIS and spatial methods play an important role in measuring potential access to health services. The Three-Step Floating Catchment Area (3SFCA) method is a GIS based procedure developed to calculate potential (spatial) accessibility as a ratio of primary health care (PHC) providers to the surrounding population in urban settings. This method uses PHC provider locations in textual/address format supplied by local, regional, or national health authorities. An automated geocoding procedure is normally used to convert such addresses to a pair of geographic coordinates. The accuracy of geocoding depends on the type of reference data and the amount of value-added effort applied. This research investigates the success and accuracy of six geocoding methods as well as how geocoding error affects the 3SFCA method. ArcGIS software is used for geocoding and spatial accessibility estimation. Results will focus on two implications of geocoding: (1) the success and accuracy of different automated and value-added geocoding; and (2) the implications of these geocoding methods for GIS-based methods that generalise results based on location data.
在加拿大和美国，衡量各个选区医疗服务提供情况的一种有效方法是评估当地或社区层面的医疗服务可及性。地理信息系统（GIS）和空间方法在衡量医疗服务潜在可及性方面发挥着重要作用。三步浮动集水区（3SFCA）方法是一种基于GIS开发的程序，用于计算城市环境中初级卫生保健（PHC）提供者与周边人口之比的潜在（空间）可及性。该方法使用由地方、区域或国家卫生当局提供的文本/地址格式的初级卫生保健提供者位置。通常使用自动地理编码程序将这些地址转换为一对地理坐标。地理编码的准确性取决于参考数据的类型以及所投入的增值工作量。本研究调查了六种地理编码方法的成功率和准确性，以及地理编码误差如何影响3SFCA方法。使用ArcGIS软件进行地理编码和空间可及性估计。研究结果将聚焦于地理编码的两个影响：（1）不同自动和增值地理编码的成功率和准确性；（2）这些地理编码方法对基于位置数据进行结果归纳的GIS方法的影响。
