Table S8.

Alternative specifications for the effect of handgun waiting periods and background checks on violence from 1970 to 2014: Poisson

1970–20141977–2014
Type of violence(1)(2)(3)
All homicide
 Waiting period−0.153 (0.049)***−0.155 (0.050)***−0.125 (0.051)**
 Background check0.007 (0.076)−0.002 (0.084)
Gun homicide
 Waiting period−0.209 (0.064)***−0.198 (0.072)***−0.177 (0.074)**
 Background check−0.039 (0.094)−0.007 (0.112)
Non-gun homicide
 Waiting period−0.031 (0.046)−0.060 (0.050)−0.012 (0.036)
 Background check0.100 (0.072)0.001 (0.055)
All suicide
 Waiting period−0.047 (0.019)**−0.076 (0.023)***−0.032 (0.010)***
 Background check0.127 (0.070)*0.032 (0.021)
Gun suicide
 Waiting period−0.089 (0.026)***−0.116 (0.030)***−0.075 (0.017)***
 Background check0.111 (0.075)0.032 (0.030)
Non-gun suicide
 Waiting period−0.010 (0.031)−0.053 (0.053)0.001 (0.032)
 Background check0.207 (0.078)***0.088 (0.031)***
  • Coefficients are based on a Poisson model for the count of deaths using adult population as the exposure variable. All models include state and year fixed effects and mirror those of Table 1. Model 3 uses fewer years of data due to missing control variables in earlier years. The analysis covering 1970–2014 includes 2,295 state-years; the analysis with control variables covering 1977–2014 includes 1,938 state-years. SEs, shown in parentheses, are clustered by state. *P < 0.10; **P < 0.05; ***P < 0.01.