Estimating spatial accessibility to facilities on the regional scale: an extended commuting-based interaction potential model.

Université de Strasbourg; Image, Ville, Environnement, Strasbourg, France.
International Journal of Health Geographics (Impact Factor: 2.62). 01/2011; 10:2. DOI: 10.1186/1476-072X-10-2
Source: PubMed

ABSTRACT There is growing interest in the study of the relationships between individual health-related behaviours (e.g. food intake and physical activity) and measurements of spatial accessibility to the associated facilities (e.g. food outlets and sport facilities). The aim of this study is to propose measurements of spatial accessibility to facilities on the regional scale, using aggregated data. We first used a potential accessibility model that partly makes it possible to overcome the limitations of the most frequently used indices such as the count of opportunities within a given neighbourhood. We then propose an extended model in order to take into account both home and work-based accessibility for a commuting population.
Potential accessibility estimation provides a very different picture of the accessibility levels experienced by the population than the more classical "number of opportunities per census tract" index. The extended model for commuters increases the overall accessibility levels but this increase differs according to the urbanisation level. Strongest increases are observed in some rural municipalities with initial low accessibility levels. Distance to major urban poles seems to play an essential role.
Accessibility is a multi-dimensional concept that should integrate some aspects of travel behaviour. Our work supports the evidence that the choice of appropriate accessibility indices including both residential and non-residential environmental features is necessary. Such models have potential implications for providing relevant information to policy-makers in the field of public health.

1 Bookmark
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In many countries, financial assistance is awarded to physicians who settle in an area that is designated as a shortage area to prevent unequal accessibility to primary health care. Today, however, policy makers use fairly simple methods to define health care accessibility, with physician-to-population ratios (PPRs) within predefined administrative boundaries being overwhelmingly favoured. Our purpose is to verify whether these simple methods are accurate enough for adequately designating medical shortage areas and explore how these perform relative to more advanced GIS-based methods. Using a geographical information system (GIS), we conduct a nation-wide study of accessibility to primary care physicians in Belgium using four different methods: PPR, distance to closest physician, cumulative opportunity, and floating catchment area (FCA) methods. The official method used by policy makers in Belgium (calculating PPR per physician zone) offers only a crude representation of health care accessibility, especially because large contiguous areas (physician zones) are considered. We found substantial differences in the number and spatial distribution of medical shortage areas when applying different methods. The assessment of spatial health care accessibility and concomitant policy initiatives are affected by and dependent on the methodology used. The major disadvantage of PPR methods is its aggregated approach, masking subtle local variations. Some simple GIS methods overcome this issue, but have limitations in terms of conceptualisation of physician interaction and distance decay. Conceptually, the enhanced 2-step floating catchment area (E2SFCA) method, an advanced FCA method, was found to be most appropriate for supporting areal health care policies, since this method is able to calculate accessibility at a small scale (e.g. census tracts), takes interaction between physicians into account, and considers distance decay. While at present in health care research methodological differences and modifiable areal unit problems have remained largely overlooked, this manuscript shows that these aspects have a significant influence on the insights obtained. Hence, it is important for policy makers to ascertain to what extent their policy evaluations hold under different scales of analysis and when different methods are used.
    BMC Family Practice 08/2013; 14(1):122. · 1.61 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Improving access to healthy foods is a promising strategy to prevent nutrition-related chronic diseases. To characterize retail food environments and identify areas with limited retail access, researchers, government programs, and community advocates have primarily used secondary retail food outlet data sources (e.g., InfoUSA or government food registries). To advance the state of the science on measuring retail food environments, this systematic review examined the evidence for validity reported for secondary retail food outlet data sources for characterizing retail food environments. A literature search was conducted through December 31, 2012, to identify peer-reviewed published literature that compared secondary retail food outlet data sources to primary data sources (i.e., field observations) for accuracy of identifying the type and location of retail food outlets. Data were analyzed in 2013. Nineteen studies met the inclusion criteria. The evidence for validity reported varied by secondary data sources examined, primary data-gathering approaches, retail food outlets examined, and geographic and sociodemographic characteristics. More than half of the studies (53%) did not report evidence for validity by type of food outlet examined and by a particular secondary data source. Researchers should strive to gather primary data but if relying on secondary data sources, InfoUSA and government food registries had higher levels of agreement than reported by other secondary data sources and may provide sufficient accuracy for exploring these associations in large study areas.
    American journal of preventive medicine 10/2013; 45(4):462-73. · 4.24 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Empirical evidence is mounting that good urban design fosters the formation of social fabric. Existing evidence is however limited in at least two respects. First, empirical studies have focused largely on social interactions taking place within the residential neighborhood, while leaving social encounters near the workplace unconsidered. Second, while various studies have examined the impact of the built environment on realized social behavior, there is as yet no empirical research on the potential for having social contact. A deeper understanding of the geography of social interaction potential is nonetheless important, for it is individuals’ social opportunities rather than their preferences and actual choices that are most directly amenable to policy intervention. This paper seeks to address both issues in an empirical case study in Flanders and Brussels (Belgium). An exploratory spatial analysis is conducted to uncover spatial trends in the potential for social interaction in order to better understand the role of urban spatial structure in the production of social interaction potential.
    Computers Environment and Urban Systems 09/2013; 41:318-331. · 1.79 Impact Factor

Full-text (2 Sources)

Available from
Jun 5, 2014