Los Angeles, CA
Prevention Institute used the USALEEP data to quantify the relationship between health outcomes and access to parks and green space at the census-tract level using associative modeling, giving them the predictive power to quantify a type of “dose-response relationship” between park access and population health. This project enabled community stakeholders to harness the data to organize, build power, and convince elected officials and other decisionmakers to prioritize parks and improvements to green infrastructure in their neighborhoods.
HOW THEY USED USALEEP DATA
The project used predictive modeling to estimate the quantitative relationship between parks, green spaces, and life expectancy. Specifically, the models estimate the relative impact that access to parks and green spaces, the "independent" variables in each model, have on life expectancy (using the USALEEP census-tract level data), which is the "dependent", or outcome variable of each model. For this analysis, the team used various census-tract level datasets including PNA mapping layers, tree canopy, normalized difference vegetation index (a measure of greenness calculated from satellite imagery), and data accounting for other social and environmental factors.
Results from the research found that increasing park acreage has the potential to increase life expectancy for LA County residents in areas that have lower tree cover or lower vegetation levels than the county median. LA County census tracts with less tree cover are typically park poor, disproportionately low income, and home to primarily people of color. If all of the census tracts in LA County with park deficits and low tree canopy levels had an increase in park acreage up to the median for LA County tracts (about 54 acres within a two-mile radius of each census tract), LA County would likely see considerable life expectancy gains for each resident living in those tracts. Increasing park acreage accessible to residents in these census tracts has the potential for considerable life expectancy gains. Approximately 164,700 years in life expectancy could be gained across the population of all people living in census tracts in LA County with park deficits and low tree canopy levels. Targeted investments in park infrastructure would significantly benefit the health of Latino and Black residents; calculating gains specifically for these two groups, targeted investments would result in an increase of almost 118,000 years of life expectancy.
In order to share their findings with the field, the Prevention Institute created the Park Equity, Life Expectancy, and Power Building Advocacy Toolkit which is comprised of documents that, together, review the evidence of park inequities, summarize new research on the relationship between park access and life expectancy in Los Angeles County, and detail the impact of these issues on three park-poor communities. These materials focus on the Los Angeles region, but are pertinent to communities throughout the US that experience similar challenges to achieving park equity. The materials in the Toolkit were designed for base-building organizations, their members, and other change agents working to build power in disinvested communities to secure equitable investments in park infrastructure.
Toolkit materials include: a project overview, research synopsis, policy brief, community profiles, and presentation materials to disseminate findings to groups advocating to prioritize public investments in communities with low life expectancy and high park need.
WHAT THEY LEARNED
The research conducted for this project is the first of its kind in the United States. Prevention Institute partnered with Dr. Michael Jerrett, Professor and Director of the Center for Occupational and Environmental Health, at the UCLA Fielding School of Public Health, and an internationally recognized expert in exposure science, built environment and environmental justice. Interestingly, one of the challenges encountered by the UCLA research team, which included doctoral student Rachel Connolly, was the profound lack of park space in Los Angeles County. With so few parks, it was initially difficult to determine the appropriate metric for park space at the census tract level to use in the statistical analysis. When confronted with this challenge in building the model, the Prevention Institute and UCLA partners engaged in a series of brainstorming sessions to identify alternative approaches for the analysis. Additionally, the UCLA partners explored and optimized a variety of different models before finalizing the model using levels of tree canopy or vegetation in relationship to lack of park space. The lesson the team learned from this was to be persistent when forging new pathways to understanding inequities in life expectancy.
The convening of a Community Advisory Board (CAB), comprised of seven base-building organizations from across Los Angeles County, provided multiple benefits that ended up being greater than the sum of its parts. Of course, the research methodology and toolkit documentation were enriched by the input of the organizers who represented these groups, but their active involvement also generated a sense of community around the issue of park inequities and power building that was new and exciting for all partners. During meetings, the discussion revealed that CAB members are very invested in the use of the life expectancy data to enable them to advocate for more equitable access to parks and open space. The conversation focused on indicators that accurately depict community environments and how the resulting statistical analysis could inform impactful advocacy materials designed for base-building and advocacy organizations and their members and constituents. CAB members expressed enthusiasm about co-creating mapping tools and advocacy materials to tell impactful stories about the essential role of parks and other green spaces in creating healthy, safe and vibrant communities. They were also excited to be part of a project that provides other community-based organizations with powerful data and materials for policy advocacy efforts to secure additional parks infrastructure improvements in high need communities throughout LA County. CAB members expressed interest in having a strategic discussion about the policy landscape to identify a platform or menu of policy advocacy opportunities that could be the focus of advocacy efforts using the Park Equity, Life Expectancy, and Power Building Advocacy Toolkit.
WHAT THEY RECOMMEND FOR SIMILAR PROJECTS
Prevention Institute has identified a few recommendations for organizations interested in conducting similar projects centering in the USALEEP data, outlined below:
- Explore the relationships between USALEEP life expectancy and multiple green space and parks metrics, including tree canopy, normalized difference vegetation index, and parks metrics. In reviewing different metrics, it is possible to find surprising results as this team did.
- Develop mapping layers with park metrics. This could include distance to parks, available park acreage, park pressure, and park amenities for the region of interest. The team was fortunate to have access to the geographic mapping tools and other data provided by the PNA. They were able to build upon the PNA and conduct analysis to explore the relationship between parks and health outcomes in LA County.
- Engage and equitably compensate power building and base building organizations in the co-creation of power building-aligned data, resources, and technical assistance. The input of CAB was invaluable to the project given their expertise in power building approaches and tactics in relation to reversing inequities and increasing park infrastructure investments in high need communities. Through funding for this project, CAB members received substantial stipends to offset CAB members’ time commitment.
To learn more, follow @preventioninst on Twitter. If you are interested in learning more about this team’s project approach or have specific questions regarding replicating their work in your community, please feel free to contact the Principal Investigator of this project, Jasneet Bains.
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