equity

Opioid treatment deserts

The latest outcome from our opioid overdose mapping project: we find disparities across neighborhoods and racial groups in access to opioid treatment providers:

Hyder A, Lee J, Dundon A, Southerland LT, All D, Hammond G, and Miller, H.J. (2021) Opioid Treatment Deserts: Concept development and application in a US Midwestern urban county. PLoS ONE 16(5): e0250324. https://doi.org/10.1371/journal.pone.0250324

Abstract

Objectives.  An Opioid Treatment Desert is an area with limited accessibility to medication-assisted treatment and recovery facilities for Opioid Use Disorder. We explored the concept of Opioid Treatment Deserts including racial differences in potential spatial accessibility and applied it to one Midwestern urban county using high resolution spatiotemporal data.
Methods

We obtained individual-level data from one Emergency Medical Services (EMS) agency (Columbus Fire Department) in Franklin County, Ohio. Opioid overdose events were based on EMS runs where naloxone was administered from 1/1/2013 to 12/31/2017. Potential spatial accessibility was measured as the time (in minutes) it would take an individual, who may decide to seek treatment after an opioid overdose, to travel from where they had the overdose event, which was a proxy measure of their residential location, to the nearest opioid use disorder (OUD) treatment provider that provided medically-assisted treatment (MAT). We estimated accessibility measures overall, by race and by four types of treatment providers (any type of MAT for OUD, Buprenorphine, Methadone, or Naltrexone). Areas were classified as an Opioid Treatment Desert if the estimate travel time to treatment provider (any type of MAT for OUD) was greater than a given threshold. We performed sensitivity analysis using a range of threshold values based on multiple modes of transportation (car and public transit) and using only EMS runs to home/residential location types.

Results. A total of 6,929 geocoded opioid overdose events based on data from EMS agencies were used in the final analysis. Most events occurred among 26–35 years old (34%), identified as White adults (56%) and male (62%). Median travel times and interquartile range (IQR) to closest treatment provider by car and public transit was 2 minutes (IQR: 3 minutes) and 17 minutes (IQR: 17 minutes), respectively. Several neighborhoods in the study area had limited accessibility to OUD treatment facilities and were classified as Opioid Treatment Deserts. Travel time by public transit for most treatment provider types and by car for Methadone-based treatment was significantly different between individuals who were identified as Black adults and White adults based on their race.

Conclusions.  Disparities in access to opioid treatment exist at the sub-county level in specific neighborhoods and across racial groups in Columbus, Ohio and can be quantified and visualized using local public safety data (e.g., EMS runs). Identification of Opioid Treatment Deserts can aid multiple stakeholders better plan and allocate resources for more equitable access to MAT for OUD and, therefore, reduce the burden of the opioid epidemic while making better use of real-time public safety data to address a public health epidemic that has turned into a public safety crisis.

Virtual workshop on Geospatial Needs for Environmental Justice

The Mapping Science Committee of the National Academies of Science, Engineering and Medicine is hosting a virtual workshop on Geospatial Needs for Environmental Justice on May 21st, 2021. This workshop will explore how geospatial data and techniques can be used to analyze and mitigate geographic sorting of social groups within communities and differential exposure to toxins and risks in built and natural environments.  It is free and open to the public.

We have a great line up of speakers!  Please join the discussion.  More information and registration: https://mscspring2021.splashthat.com/

Analyzing collective accessibility using average space-time prisms

New publication:  Lee, J. and Miller, H.J. (2019) “Analyzing collective accessibility using average space-time prisms,” Transportation Research Part D: Transport and Environment, 69, 250-264.

Abstract:  The space-time prism (STP) is the envelope of all possible travel paths in space and time between two anchor locations and times, measuring accessibility for an individual given a designated travel and activity episode. Although the STP provides a powerful measure of individual accessibility, transportation researchers often need to analyze accessibility at collective-levels for planning and policy analysis. Deriving a representative STP of a set of individual STPs would provide a general idea of how collective members’ accessibility is performing. However, there is no analytical time geographic method to calculate a collective-level representative STP that is consistent with individual STPs. To fill this gap, this research develops the concept of average space-time prism (ASTP). The ASTP is a representative STP of a group of individual STPs with respect to size, shape, and location. We develop methods for calculating an ASTP using analytical time geography and elliptic Fourier shape analysis techniques. The ASTP provides a geometric and visual summary of collective accessibility: it can be used to generate representative STPs for aggregate geographic units such as neighborhoods and cities based on individual-level data. A possible application of the ASTP is the spatial equity analysis of accessibility. The ASTP can be located at individuals’ anchor locations and overlaid with opportunities, enabling in-situ comparisons between individual versus collective accessibility and accessibility equity analysis considering geographic contexts. We illustrate this ASTP’s capability when measuring the impacts of new transit service on healthcare access equity in a neighborhood in Columbus, Ohio, USA.