TABLE 1—
Variables and Data Sources in Study of Gun Ownership and Firearm Homicide Rates: United States, 1981–2010
| Variable | Definition | Source | Notes |
| Firearm homicides | Rate/100 000 population, adjusted to 2000 age distribution | WISQARS8 | Missing data for NH 2008–2010; ND 2008–2010; VT 2008–2010; WY 2008, 2010; HI 2010; SD 2010 |
| Prevalence of gun ownership | Proportion of suicides committed with a firearm | WISQARS8 | Complete panel seriesa |
| Age | Percentage of population aged 15–29 y | WISQARS8 | Complete panel seriesa |
| Gender | Percentage of population aged 15–29 y who are male | WISQARS8 | Complete panel seriesa |
| Race/ethnicity | |||
| Black | Percentage of Blacks in population | WISQARS8 | Complete panel seriesa |
| Hispanic | Percentage of Hispanics in population | US Census Bureau58 | Complete panel seriesa |
| Poverty | Percentage of population living in poverty | US Census Bureau61 | Complete panel seriesa |
| Unemployment | Percentage unemployed among civilian labor force, aged ≥ 16 y | US Bureau of Labor Statistics62 | Complete panel seriesa |
| Household income | Median household income (in 2010 dollars) | US Bureau of the Census63 | Data extrapolated for 1981–1983 |
| Educational attainment | Percentage of adults aged ≥ 25 y with college degree (≥ bachelor's) | US Census Bureau60 | Data interpolated for 1981–1988 and 1992 |
| Income inequality | Gini coefficient | US Census Bureau64 | Data interpolated for 1981–1988, 1990–1998, 2000–2005; variable rescaled in final model to ease interpretation of parameter estimate |
| Urbanization | Percentage of population living in urbanized area or urban cluster | US Census Bureau59 | Data interpolated for 1991–1999 and 2001–2009; data extrapolated for 1981–1989 because 1980 Census definition of urban was different |
| Alcohol | Per capita alcohol consumption among persons aged ≥ 14 y | National Institute of Alcoholism and Alcohol Abuse65 | Complete panel seriesa |
| Violent crime | Rates of aggravated assault, robbery, and forcible rape/100 000 population | Federal Bureau of Investigation66 | Complete panel seriesa; variable rescaled in final model to ease interpretation of parameter estimate |
| Nonviolent crime | Rate of property crime (burglary, larceny–theft, and motor vehicle theft)/100 000 population | Federal Bureau of Investigation66 | Complete panel seriesa; variable rescaled in final model to ease interpretation of parameter estimate |
| Hate crime | Rate of hate crimes against persons/1 000 000 population | Federal Bureau of Investigation67 | Data available for 1995–2010; data from 1995 used for 1981–1994 |
| Divorce | Rate/1000 population | National Center for Health Statistics69; US Census Bureau59 | Data interpolated for 1986 in all states, interpolated for many years for CA, GA, HI, IN, LA, and MN |
| Hunting licenses | Proportion of population aged ≥ 15 y licensed | US Fish and Wildlife Service68 | Complete panel seriesa |
| Region | Census region | US Census Bureau70 | Complete panel seriesa |
| Nonfirearm homicides | Rate/100 000 population, adjusted to 2000 age distribution | WISQARS8 | Missing data for NH 2008–2010; ND 2008–2010; VT 2008–2010; WY 2008, 2010; HI 2010; SD 2010 |
| Incarceration | Prisoners with sentence of > 1 y/100 000 population | Bureau of Justice Statistics71 | Data interpolated for 1981, 1982, and 1992 |
| Suicide | No./100 000 population | WISQARS8 | Complete panel seriesa |
Note. WISQARS = Web-Based Injury Statistics Query and Reporting Systems.
a
All 50 states, 1981–2010.