Protocol - Tobacco Retailer Density/Proximity - To Schools

Description

The Luke et al. protocol uses Geographic Information Systems (GIS) to assess the tobacco retailer proximity to schools.

Specific Instructions

Collectively, this measure for tobacco retailer density/proximity includes the following components:

Valid data sources providing the location of tobacco product retailers are required.
Proximity of tobacco retailers may be computed for residence, schools, or other locations (e.g., distance between two retailers). Both the Duncan et al., and Young-Wolff et al., protocol measure the distance from a known residence to the nearest tobacco retailer in roadway miles and the latter contains a discussion about data confidentiality.

For any density/proximity measure, the WG suggests using GIS software, such as ESRI ArcGIS version 10.1 (ESRI, Redlands, CA). Investigators without such software or expertise may employ a third party vendor to compute these measures for a nominal cost. Multiple steps are required:

Obtain address data for licensed or likely tobacco retailers: Where there are state or local tobacco retailer licensing requirements, the investigator may obtain retailer addresses from the appropriate licensing authority. When licensing is not required or unavailable to researchers, address lists for likely tobacco retailers may be obtained from commercial vendors (e.g., Dun & Bradstreet), along with some determination of whether or not they sell tobacco products, or investigators may use on-the-ground assessments to identify tobacco retailers in communities.
Geocode the latitudes and longitudes of addresses for tobacco retailers and participants’ residences (and/or schools and workplaces). Mapping rates of 90% or greater are typical, but the mapping rate depends on the individual data set and one would expect lower rates in rural areas. When geocoding residential address data to a random shift may be employed to avoid incidental disclosure for shared data.
Define neighborhood: Egocentric neighborhoods (also referred to as "egocentric buffers" and "egohoods") are defined by a radius around a particular location, such as a residence, and these definitions are preferred by both the Young-Wolff and Duncan protocols. Network-based data better captures the travel distance necessary to obtain tobacco products from retailers nearest to participants’ residence. The appropriate distance (400m, 500m, 800m, 1km) depends on the research question. Street-network buffers excluding highways and ramps are created by using software similar to ESRI’s ArcGIS 10 Buffer tool, ArcGIS 10 Data and Maps, and ArcGIS Network Analysis Extension. According to the Duncan protocol, when residential address data are unavailable, alternative definitions of neighborhood are administrative units, such as census block group, tract, zip code tabulation area, city or county.
Extract census data to characterize each neighborhood: Use data from decennial census or intercensal estimates to compute the land area (or other attribute, such as roadway miles, population size). When buffers overlap multiple tracts, buffer characteristics are weighted in proportion to tract area inside the buffer.
Compute density: Use software (such as ArcGIS Spatial Join tool) or third-party vendor to calculate the count of tobacco retailers in each neighborhood, and compute retailer density by dividing by the count of retailers by the area attribute of interest (e.g., acres or roadway miles or population size).
Compute proximity: Use ArcGIS Closest Facility tool (or comparable tool in alternate software) to determine the distance between two points, such as the straight-line distance between a school boundary and a tobacco retailer.

Availability

Available

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Protocol

Proximity of Tobacco Retailers to Schools

1. The Luke protocol obtained data for tobacco retailers from the state departments of education (school location data may also be obtained from local or federal departments of education). GIS shapefiles for parks and city schools were also obtained. The shapefiles allow mapping of the actual park and school boundaries.

2. GIS analysis was then performed by entering all data into ArcMap 9.3. A proximity analysis was conducted to assess the potential impact of the Family Smoking Prevention and Tobacco Control Act (FSPTCA) 1000-foot ban on retailers near schools and parks. Buffer zones of varying distances (350, 500, 1000 feet) around all local parks and parcels containing schools were constructed. The count and percentage of tobacco retailers falling within these buffers were then calculated. This analysis was just done for select cities because GIS shapefiles were not available statewide for all school boundaries.

3. To perform the statewide analyses (where actual school perimeter data were not available), the Luke protocol used radial buffers that were constructed around the school address center points to approximate the perimeter buffers. The recommended approach, when possible, is to use the actual school property boundary shapefile as described in the description in #2 above rather than the radial buffer approach described here.

Personnel and Training Required

Personnel must have GIS expertise as a result of training or education (e.g., GIS Specialist).

Knowledge of census data products and websites such as American Factfinder (http://factfinder.census.gov) and/or commercial geospatial data products

After extracting the necessary data, statistical methods are used (e.g., principal component analysis (PCA) and factor analysis).

Equipment Needs

Geospatial Data Prouducts

Requirements

Requirement Category	Required
Major equipment	No
Specialized training	No
Specialized requirements for biospecimen collection	No
Average time of greater than 15 minutes in an unaffected individual	Yes

Mode of Administration

Secondary Data Analysis

Lifestage

Infant, Toddler, Child, Adolescent, Adult, Senior, Pregnancy

Participants

Selection Rationale

The Luke et al. protocol provides examples of using geolocation data to measure the spatial relation of tobacco retailers to a respondent’s school.

Language

English

Standards

Standard	Name	ID	Source
caDSR Form	PhenX PX741203 - Tobacco Retailer Density School	6873883	caDSR Form

Derived Variables

None

Process and Review

Not applicable.

Protocol Name from Source

Luke, D., et al. Family Smoking Prevention and Tobacco Control Act: Banning Outdoor Tobacco Advertising Near Schools and Playgrounds, Am J Prev Med, 2011

Source

Luke D, et al. Family Smoking Prevention and Tobacco Control Act: Banning Outdoor Tobacco Advertising Near Schools and Playgrounds, Am J Prev Med. 2011; 40(3)295-302.

General References

Young-Wolff K, et al. Tobacco Retailer Proximity and Density and Nicotine Dependence Among Smokers With Serious Mental Illness, Am J Public Health. 2014;104:

1454-1463. doi:10.2105/AJPH.2014.301917.

Duncan D, et al. Examination of How Neighborhood Definition Influences Measurements of Youths’ Access to Tobacco Retailers: A Methodological Note on Spatial Misclassification, Am J Epidemiol. 2014;179(3):373-381

Frank LD, Schmid TL, Sallis JF, Chapman J, Saelens BE. Linking objectively measured physical activity with objectively measured urban form: ﬁndings from SMARTRAQ. Am J Prev Med. 2005;28(suppl 2):117---125.

Timperio A, Crawford D, Telford A, et al. Perceptions about the local neighborhood and walking and cycling among children. Prev Med. 2004;38(1):39-47.

Colabianchi N, Dowda M, Pfeiffer KA, et al. Towards an understanding of salient neighborhood boundaries: adolescent reports of an easy walking distance and convenient driving distance. Int J Behav Nutr Phys Act. 2007;4:66.

Protocol ID

741203

Variables

Export Variables

Variable Name	Variable ID	Variable Description	dbGaP Mapping
PX741203_Tobacco_Retailer_Density_School1000
	PX741203030100	What is the number of tobacco retailers more within 1000 meter service area around each local park and parcel containing schools? show less	N/A
PX741203_Tobacco_Retailer_Density_School1000_Calculated
	PX741203030200	What is the density? (Divide count by land more area for each buffer. Land area is to be extracted from Census 2010 data) show less	N/A
PX741203_Tobacco_Retailer_Density_School350
	PX741203010100	What is the number of tobacco retailers more within 350 meter service area around each local park and parcel containing schools? show less	N/A
PX741203_Tobacco_Retailer_Density_School350_Calculated
	PX741203010200	What is the density? (Divide count by land more area for each buffer. Land area is to be extracted from Census 2010 data) show less	N/A
PX741203_Tobacco_Retailer_Density_School500
	PX741203020100	What is the number of tobacco retailers more within 500 meter service area around each local park and parcel containing schools? show less	N/A
PX741203_Tobacco_Retailer_Density_School500_Calculated
	PX741203020200	What is the density? (Divide count by land more area for each buffer. Land area is to be extracted from Census 2010 data) show less	N/A

Tobacco Regulatory Research: Vector

Measure Name

Tobacco Retailer Density/Proximity

Release Date

October 17, 2016

Definition

Using geospatial data, density measures the spatial concentration of tobacco retailers in a neighborhood, defined by either an area centered on a respondent’s residence, school/workplace, or an administrative area, such as counties, school districts, or census tracts. Proximity measures distance to the nearest tobacco retailer from a point of interest (e.g., residence, school/workplace, or another retailer).

Purpose

There is growing evidence that tobacco retailers are concentrated in areas of economic disadvantage, and that greater physical access is associated with increased tobacco use, particularly among youth. There is some evidence that proximity to tobacco retailers is associated with lower efficacy to quit and less success with quitting. This measure describes the retail availability of tobacco products by characterizing the quantity and location of retailers with respect to a respondent’s residence, school or workplace.

Keywords

residence, neighborhood, Tobacco Retailer, Tobacco Advertising, Proximity, Density, retail, geocode, geocoding, geographic information systems, availability, access.

Measure Protocols

Protocol ID	Protocol Name
741201	Tobacco Retailer Density/Proximity - Administrative Neighborhoods
741202	Tobacco Retailer Density/Proximity - Known Residence
741203	Tobacco Retailer Density/Proximity - To Schools

Publications

Garcia-Cazarin, M.L., Mandal, R.J., Grana, R., Wanke, K.L., Meissner, H. (2020) Host-agent-vector-environment measures for electronic cigarette research used in NIH grants. Tobacco Control. 2020 January; 29(1). doi: 10.1136/tobaccocontrol-2017-054032