Investigating place effects on health: A spatial approach vs. a conventional contextual approach

Basile Chaix, PhD¹, Juan Merlo, MD PhD Asso Prof², and Pierre Chauvin, MD, PhD, DSc¹. (1) Research team on social determinants of health and utilization of care, National Institute of Health and Medical Research, INSERM U444, Faculté Saint-Antoine, 27 rue Chaligny, Paris Cedex 12, 75571, France, 33144738443, chaix@u444.jussieu.fr, (2) Department of Community Medicine (section of Preventive Medicine), Malmö University Hospital, Faculty of Medicine, Lund University, S-205 02, Malmö, Sweden

Past studies that have investigated place effects on health have been conducted with the contextual approach where variations in a space fragmented into areas are investigated with multilevel analyses. Conversely, we operationalize a continuous concept of space with a geographic information system, and propose to use spatial modeling techniques and place indicators that continuously consider the space around the individuals’ place of residence. To compare this spatial approach with the more conventional contextual approach, we investigated geographic variations of healthcare utilization behavior in France. Spatial mixed models indicated that the correlation in the risk of not having a regular primary care physician was 0.028 for individuals located at the same place, but only 0.015 for individuals located 10 kilometers away (figures were 0.029 and 0.026 for having a high percent of consultations with specialists). Spatial models had a better fit to the data than multilevel models. The socioeconomic level in the place of residence and the supply of physicians were independently associated with healthcare utilization behavior. Associations were stronger when measuring place indicators within a continuous space than within the usual administrative areas. These different approaches for measuring place effects also lead to different pictures when identifying places at risk on a geographical information system. Considering the space in its continuity may be promising for investigating place effects on health with individual data.

Learning Objectives:

At the conclusion of the session, the participant in this session will be able to

3. List the different drawbacks of the usual multilevel analytic approach based on the conception of an area divided into often arbitrary subareas.
6. Recognize the advantages of spatial regression techniques for analyzing geographic variations of health-related outcomes.
9. Assess the usefulness of geographical information systems for defining place explanatory characteristics.

Keywords: Geographic Information Systems, Biostatistics

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.

Recorded presentation

Information and GIS Systems for Public Health Practice

The 132nd Annual Meeting (November 6-10, 2004) of APHA