Census tract measures, definition, data source and year
| Measure | Definition | Data source | Year |
|---|---|---|---|
| Social disorder component | |||
| Per cent vacant housing units | Per cent vacant residential housing units | USA Department of Housing and Urban Development and US Postal Service | 2013 |
| Violent crime rate | Total murder, non-negligent manslaughter, forcible rape, robbery and aggravated assaults per 1000 tract residents* | Law Enforcement Agencies (ie, police department, Sheriff's Office) | 2013 |
| STI prevalence | Prevalence of newly reported STIs (ie, chlamydia, gonorrhoea and primary and secondary syphilis) per 1000 tract residents aged 15–64 years† | State Department of Health | 2013 |
| Per cent poverty | Per cent residents with annual income below poverty level | American Community Survey (ACS) | 2009–2013 |
| Per cent unemployment | Per cent unemployed residents aged ≥16 years | ACS | 2009–2013 |
| Social disadvantage component | |||
| Per cent renter-occupied housing units | Per cent renter-occupied housing units | ACS | 2009–2013 |
| Alcohol outlet density | The number of businesses with a license to sell beverages containing alcohol (eg, liquor, beer, wine) for off-premise consumption per tract square mile*‡ | State Licensing Agencies (eg, Department of Revenue, Alcoholic Beverage Control Commission) | 2014 |
*Addresses were obtained from state agencies and geocoded to tracts; addresses within a 100-foot buffer of the tract boundary were included in the tract's calculation.
†In Alabama, the number of newly identified STIs was available by ZIP code, but not census tract. ZIP-level STI counts were allocated to tracts based on the proportion of residential population using the 2015 boundaries USPS-HUD ZIP to tract crosswalk file. Twelve ZIP code-census tract combinations were not included in the crosswalk file. For these 15 participants (17% of participants with available census tract data at site), ZIP code STI prevalence was assigned to the participant census tract. We conducted sensitivity analyses, removing these participants from the analytic data set, to explore potential bias introduced by this substitution. The rounded Full Model OR estimate with and without these 15 participants was the same.
‡In Mississippi, off-premise liquor licensing data were available (liquor can only be purchased at package/liquor stores), but licensing data for sale of beer and wine off-premise were not publicly available. As a proxy, we used non-restaurant businesses with permits to sell eggs or milk (eg, convenience stores, pharmacies) under the oversight of the Mississippi Department of Agriculture and Commerce because these types of businesses would have refrigerated display cases and likely have the capacity to sell beer and wine.