258339 More than distance: Novel techniques for measuring access to built environment assets

Tuesday, October 30, 2012 : 12:50 PM - 1:10 PM

Megan Wall, MPH , Program on Health, Equity, and Sustainability, San Francisco Department of Public Health, San Francisco, CA
Rajiv Bhatia, MD, MPH , Occupational and Environmental Health, San Francisco Department of Public Health, San Francisco, CA
Erika Rincon Whitcomb , School of Public Health; Department of City & Regional Planning, University of California Berkeley, San Francisco, CA
The quality and accessibility of built environment infrastructure, including public schools, parks, grocery stores, and transit, are increasingly recognized as important determinants of health. However, measures of access to such built environment assets often rely on simple counts of resources within a defined geographic boundary or buffer analysis to determine whether a population is or is not within a distance of an asset. These methods do not account for artificial borders, such as neighborhoods, which people travel between, or do not allow for quantification of the volume, quality, or relative proximity of multiple assets.

In many urban areas, sufficient data exist to create spatially refined measures of accessibility that account cumulatively for quality, relative distance, and total volume of assets. For example, retail food establishments within a defined distance of an intersection can each be weighted for their healthfulness and distance from the intersection. The sum of the assets, weighted for healthfulness and distance, can then be normalized to create an access score for each intersection. These intersection access scores can be interpolated onto a continuous surface, describing relative access to different types of resources at any point across the city. The resulting maps provide understandable and compelling portraits of which parts of the city are amenity rich or amenity poor.

This session will discuss the application of this methodology to measuring relative access to schools, parks, transit, and healthy food retail in San Francisco, California. We will provide results from our analyses and interpretation of their implications. We will then review some strengths and limitations of this approach to understanding current environmental deficiencies and utilizing this information for future planning. This session will end with a discussion of how various stakeholders might use the results from these analyses to advance equity in access to high quality environmental resources.

Learning Areas:
Environmental health sciences
Other professions or practice related to public health

Learning Objectives:
1) Describe how the San Francisco Department of Public Health has used analysis of environmental assets and hazards to influence built environment decision-making. 2) Explain novel methodological approaches to defining relative access to schools, parks, transit, and retail food over a continuous surface in a manner that accounts for quality, quantity, and distance. 3) Identify how this new methodology might be useful for various stakeholders in advancing equity in access to important environmental assets.

Keywords: Access, Environment

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I manage the San Francisco Department of Public Health's Healthy Development Measurement Tool (HDMT), a comprehensive, web-based toolkit for the consideration of health in urban development. I have facilitated the update of over 100 indicators of community health and sustainability and have spearheaded the creation of new indicators to measure food, school, open space, and transit access in San Francisco, CA.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.