TABLE 1.
—Crude Incidence Rate Ratios of Regional Homicide in the United States by Region-Level Proxies of Firearm Prevalence, 1988–1997
| Victim Age | Homicide (95% CI) | Gun-Related Homicide (95% CI) | Non–gun-Related Homicide (95% CI) |
| 0–4 years | |||
| FS/S | 1.11 (0.98, 1.24)* | 1.22 (1.10, 1.35)† | 1.09 (0.97, 1.24) |
| GSS ANY GUN | 1.08 (0.98, 1.20) | 1.24 (1.13, 1.36)† | 1.06 (0.96, 1.18) |
| GSS HANDGUN | 1.07 (0.97, 1.18) | 1.20 (1.07, 1.34)*** | 1.06 (0.95, 1.17) |
| 5–14 years | |||
| FS/S | 1.15 (1.02, 1.29)** | 1.21 (1.03, 1.42)** | 1.05 (0.98, 1.12) |
| GSS ANY GUN | 1.11 (0.98, 1.26) | 1.15 (0.94, 1.39) | 1.05 (0.97, 1.11) |
| GSS HANDGUN | 1.14 (1.02, 1.26)** | 1.20 (1.02, 1.41)** | 1.04 (0.98, 1.11) |
| 15–24 years | |||
| FS/S | 1.10 (0.90, 1.34) | 1.11 (0.89, 1.39) | 1.07 (0.96, 1.20) |
| GSS ANY GUN | 1.04 (0.87, 1.24) | 1.04 (0.85, 1.27) | 1.02 (0.93, 1.12) |
| GSS HANDGUN | 1.10 (0.92, 1.31) | 1.11 (0.91, 1.35) | 1.07 (0.96, 1.20) |
| 25–34 years | |||
| FS/S | 1.24 (1.00, 1.53)* | 1.26 (0.99, 1.61)* | 1.17 (1.01, 1.37)* |
| GSS ANY GUN | 1.16 (0.96, 1.40) | 1.18 (0.95, 1.46) | 1.11 (0.98, 1.26)* |
| GSS HANDGUN | 1.21 (1.01, 1.47)** | 1.24 (1.00, 1.54)** | 1.15 (1.01, 1.32)** |
| 35–44 years | |||
| FS/S | 1.35 (1.09, 1.66)*** | 1.44 (1.13, 1.84)*** | 1.19 (1.02, 1.39)† |
| GSS ANY GUN | 1.26 (1.05, 1.53)** | 1.34 (1.07, 1.67)** | 1.14 (0.99, 1.30)* |
| GSS HANDGUN | 1.31 (1.09, 1.58)*** | 1.39 (1.13, 1.73)*** | 1.17 (1.02, 1.34)** |
| 45–54 years | |||
| FS/S | 1.32 (1.10, 1.59)*** | 1.43 (1.18, 1.73)† | 1.16 (0.97, 1.38)* |
| GSS ANY GUN | 1.25 (1.05, 1.49)** | 1.35 (1.12, 1.63)*** | 1.10 (0.95, 1.28) |
| GSS HANDGUN | 1.30 (1.10, 1.54)*** | 1.40 (1.17, 1.67)† | 1.14 (0.98, 1.33)* |
| 55–64 years | |||
| FS/S | 1.35 (1.19, 1.53)† | 1.48 (1.29, 1.70)† | 1.21 (1.07, 1.36)*** |
| GSS ANY GUN | 1.27 (1.11, 1.45)*** | 1.39 (1.16, 1.63)† | 1.14 (1.02, 1.27)** |
| GSS HANDGUN | 1.32 (1.17, 1.50)† | 1.44 (1.26, 1.65)† | 1.19 (1.06, 1.33)*** |
| ≥ 65 years | |||
| FS/S | 1.38 (1.20, 1.59)† | 1.63 (1.44, 1.85)† | 1.26 (1.09, 1.45)*** |
| GSS ANY GUN | 1.31 (1.13, 1.51)† | 1.51 (1.28, 1.80)† | 1.21 (1.05, 1.38)** |
| GSS HANDGUN | 1.35 (1.18, 1.56)† | 1.60 (1.36, 1.88)† | 1.23 (1.07, 1.40)*** |
| All ages | |||
| FS/S | 1.23 (1.02, 1.49)** | 1.27 (1.02, 1.58)** | 1.16 (1.01, 1.33)** |
| GSS ANY GUN | 1.16 (0.98, 1.38)* | 1.19 (0.97, 1.45)* | 1.11 (0.98, 1.25)* |
| GSS HANDGUN | 1.21 (1.02, 1.44)** | 1.25 (1.03, 1.52)** | 1.14 (1.01, 1.29)** |
Note. CI = confidence interval. Regional household firearm ownership prevalence was estimated using 3 measures: (1) a proxy representing the percentage of suicides that are firearm suicides (FS/S), (2) household gun ownership rates as reported in the General Social Survey (GSS ANY GUN), and (3) household handgun ownership rates as reported in the General Social Survey (GSS HANDGUN). All measures are standardized at the regional level so that their mean equals 0 and their standard deviation equals 1. Incidence rate ratios correspond to the standardized proxies. Over the 10-year study period, on average, our proxies vary across regions by 3.1, 3.4, and 3.4 standard deviations for FS/S, GSS ANY GUN, and GSS HANDGUN, respectively. Longitudinal variation is an order of magnitude smaller: over time, FS/S, GSS ANY GUN, and GSS HANDGUN measures fall within 0.35, 0.33, and 0.34 standard deviations of one another. Overall, when each region assumes a distinct prevalence estimate for each year, proxies span 3.6, 4.5, and 4.7 standard deviations for FS/S, GSS ANY GUN, and GSS HANDGUN, respectively.
*P < 0.1; **P < 0.05; ***P < 0.01; †P < 0.001. All P values are two-tailed.