Table 3. Difference-in-Differences Analyses for Proportion of Individuals With a New Suicide Prevention Safety Plan Documentation and Mortality Outcomes in Subsequent 6 Months.

Outcome	REACH VET era			Pre–REACH VET era			Difference-in-difference, mean (95% CI)a
	Risk tier, mean (SD), proportion		Difference, mean (95% CI)b	Risk tier, mean (SD), proportion		Difference, mean (95% CI)b	Unadjusted	Adjusting for age and sex
	Top 0.1%	Top 0.3%-0.1%		Top 0.1%	Top 0.3%-0.1%
With a new safety planc	0.1680 (0.3739)	0.0558 (0.2295)	0.1123 (0.1046 to 0.1199)	0.1284 (0.3345)	0.0523 (0.2226)	0.0761 (0.0702 to 0.0820)	0.0362 (0.0266 to 0.0458)	0.0768 (0.0561 to 0.0974)
All-cause mortalityd	0.0217 (0.1456)	0.0317 (0.1752)	−0.0100 (−0.0121 to −0.0079)	0.0195 (0.1381)	0.0286 (0.1668)	−0.0092 (−0.0113 to −0.0071)	−0.0009 (−0.0038 to 0.0021)	0.0000 (−0.0001 to 0.0001)
Cause-specific mortalitye
Suicide	0.0028 (0.0526)	0.0016 (0.0395)	0.0012 (0.0005 to 0.0019)	0.0025 (0.0501)	0.0018 (0.0427)	0.0007 (0.0000 to 0.0013)	0.0005 (−0.0004 to 0.0015)	0.0007 (−0.0006 to 0.0019)
Nonsuicide external cause	0.0052 (0.0720)	0.0043 (0.0651)	0.0010 (−0.0001 to 0.0020)	0.0038 (0.0617)	0.0030 (0.0546)	0.0008 (0.0000 to 0.0016)	0.0001 (−0.0012 to 0.0014)	0.0001 (−0.0015 to 0.0018)
All-causef	0.0223 (0.1476)	0.0320 (0.1760)	−0.0097 (−0.0121 to −0.0073)	0.0192 (0.1371)	0.0283 (0.1659)	−0.0092 (−0.0112 to −0.0071)	−0.0005 (−0.0037 to 0.0026)	0.0001 (−0.0001 to 0.0002)

^aREACH VET era − pre–REACH VET Era.

^bMean difference (top 0.1% − top 0.3% to 0.1%).

^cCohorts were limited to those with no safety plan in the prior 2 years, for a total of 77 625 individuals.

^dMortality ascertained from the Vital Status File. Cohorts were limited to those for whom vital status could be ascertained, for a total of 173 305 individuals.

^eMortality ascertained from the Mortality Data Repository. Cohorts were limited to those for whom cause of death could be ascertained, for a total of 152 515 individuals.

^fAdjusted analyses used a modified Poisson model.