Effect on background checks of newly-enacted comprehensive background check policies in Oregon and Washington: a synthetic control approach

Table 2 Change in handgun background check rate (per 100,000 People) after implementation of CBC policies in Oregon and Washington, January 1999 to December 2018

Measure	Oregon^a	Washington
Observed mean rate of BCs in treated states following implementation	349.9	237.7
Counterfactual mean rate of BCs following implementation	297.1	228.6
Absolute difference in BC rate following implementation^b	52.8	9.1
Estimated % difference in BC rate following implementation^c	18.0	4.0
N states in the donor pool with change ≥ treated state (n = 28)^d	2	9

CBC comprehensive background checks, BCs background checks
^a Permutation test for Alaska did not converged, resulting in 27 control states. ^b Mean difference in background check rate between the treated states and their synthetic control after policy implementation. ^c Percentage difference in background checks rate in reference to BC rate of the synthetic controls after policy implementation. ^d Results from permutation test, measured as the post-intervention RMSPE/pre-intervention RMSPE

ISSN: 2197-1714