Meta Data Name: Access to Pharmacies
Date Added: January 6, 2021
Author: Susan Paykin
Date Last Modified: January 3, 2024
Last Modified By: Wataru Morioka
Environment
You can find the variables described in this document in the CSV files here.
CSV files are organized by year and spatial scale. For example, county-level variables from 2000 will be found in C_2000.csv.
Note: Every variable can be found in the Latest files.
Pharmacy locations were sourced from the InfoGroup (now Data Axle) 2019 Business and Consumer Historical Datafile, available through the University of Chicago Library.
Zip code tract area (ZCTA) and Census Tract files were sourced from the US Census Bureau, TIGER/Line Shapefiles 2018.
The source InfoGroup dataset includes the business name, location (address, city, state, census tract, latitude, longitude), NAICS Code, and NAICS Code Description variables.
Data was downloaded and sourced from InfoGroup's historical dataset, filtered for pharmacies via NAICS class code 4461100, cleaned, and then converted to spatial data.
Next, the nearest resource analysis was conducted using minimum Euclidean distance as a proxy variable for access. This analysis included calculating centroids for all U.S. census tracts and ZCTAs, identifying the nearest pharmact to each tract/ZCTA centroid, then measuring the distance in miles.
We calculated travel-network access metrics for the driving travel time to the nearest pharmacy location and count of pharmacies within a 30 minute driving threshold. The driving travel cost matrices were sourced from Project OSRM and are available at the Tract or ZCTA scales for mulitple transit modes via this Box folder. This analysis was conducted in Python. The script is available in code/Access Metrics - Health Resources.
County and state-level variables include the count of Census tracts and the percent of Census tracts located within a 30 minute driving threshold of an FQHC, as well as the mean (average) driving time in minutes from Census tracts within the county or state.
- Variable -- title of variable
- Variable ID -- exact name of variable in datasets
- Description -- Short description of variable
- Years Available -- years for which data exists for this variable
- Spatial Scale -- the variable exists for these levels of spatial scale
| Variable | Variable ID in .csv | Description | Years Available | Spatial Scale |
|---|---|---|---|---|
| Distance to nearest pharmacy | RxMinDis | Euclidean distance* from tract/zip centroid to the nearest pharmacy, in miles | Latest | Tract, Zip |
| Driving time to nearest pharmacy | RxTmDr | Driving time from tract/zip origin centroid to the nearest tract/zip pharmacy destination centroid, in minutes | Latest | Tract, Zip |
| Count of pharmacies | RxCntDr | Count of pharmacies within a 30-minute driving threshold | Latest | Tract, Zip |
| Variable | Variable ID in .csv | Description | Years Available | Spatial Scale |
|---|---|---|---|---|
| Count of tracts | TotTracts | Total number of tracts in county/state | Latest | County, State |
| Count of tracts within 30-min driving range | RxCtTmDr | Number of tracts with pharmacy within a 30-min driving range | Latest | County, State |
| Average time drive to nearest pharmacy | RxAvTmDr | Average driving time (minutes) across tracts in county/state to nearest pharmacy | Latest | County, State |
| Percent of tracts within 30-min driving range | RxTmDrP | Percent of tracts with pharmacy within a 30-min driving range | Latest | County, State |
*Euclidean distance or straight-line is a simple approximation of access or travel from an origin centroid to the nearest hospital. It is not a precise calculation of real travel times or distances.
The final dataset includes US states and Washington, D.C., but does not include territories (Puerto Rico, Guam, Northern Mariana Islands, American Samoa, Palau). ZCTA and tract centroids are not population-weighted.