Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Mar;33(2):237-243.
doi: 10.1038/s41370-022-00414-z. Epub 2022 Feb 10.

Impacts of the choice of distance measurement method on estimates of access to point-based resources

Amruta Nori-Sarma  1   2 , Keith R Spangler  3   4 , Biqi Wang  4   5 , Nina Cesare  4 , Kimberly A Dukes  4   5 , Kevin J Lane  3   4
Affiliations

Impacts of the choice of distance measurement method on estimates of access to point-based resources

Amruta Nori-Sarma et al. J Expo Sci Environ Epidemiol. 2023 Mar.

Abstract

Background/objective: Lack of access to resources such as medical facilities and grocery stores is related to poor health outcomes and inequities, particularly in an environmental justice framework. There can be substantial differences in quantifying "access" to such resources, depending on the geospatial method used to generate distance estimates.

Methods: We compared three methods for calculating distance to the nearest grocery store to illustrate differential access at the census block-group level in the Atlanta metropolitan area, including: Euclidean distance estimation, service areas incorporating roadways and other factors, and cost distance for every point on the map.

Results: We found notable differences in access across the three estimation techniques, implying a high potential for exposure misclassification by estimation method. There was a lack of nuanced exposure in the highest- and lowest-access areas using the Euclidean distance method. We found an Intraclass Correlation Coefficient (ICC) of 0.69 (0.65, 0.73), indicating moderate agreement between estimation methods.

Significance: As compared with Euclidean distance, service areas and cost distance may represent a more meaningful characterization of "access" to resources. Each method has tradeoffs in computational resources required versus potential improvement in exposure classification. Careful consideration of the method used for determining "access" will reduce subsequent misclassifications.

Keywords: Disparities; Exposure differences; Geospatial analysis; Resource access.

PubMed Disclaimer

References

    1. Sexton K. Socioeconomic and racial disparities in environmental health: is risk assessment part of the problem or part of the solution? Hum Ecol Risk Assess Int J. 2000;6:561–74. http://www.tandfonline.com/doi/abs/10.1080/10807030008951330 . - DOI
    1. Lee C. Environmental justice: building a unified vision of health and the environment. Environ Health Perspect. 2002;110 SUPPL. 2:141–4. - DOI - PubMed - PMC
    1. Walker RE, Keane CR, Burke JG. Disparities and access to healthy food in the united states: a review of food deserts literature. Heal Place. 2010;16:876–84. https://doi.org/10.1016/j.healthplace.2010.04.013 . - DOI
    1. Morland K, Wing S, Diez Roux A, Poole C. Neighborhood characteristics associated with the location of food stores and food service places. Am J Prev Med. 2002;22:23–9. - DOI - PubMed
    1. Phibbs CS, Luft HS. Correlation of travel time on roads versus straight line distance. Med Care Res Rev. 1995;52:532–42. http://journals.sagepub.com/doi/10.1177/107755879505200406 . - DOI - PubMed

Publication types

LinkOut - more resources