Table 3

Rate ratios for homicide and suicide rates post-law compared with pre-law by age group, United States, 1979–98*

	Minimum age of 21 years for purchase				Minimum age of 21 years for possession
	Homicide		Suicide		Homicide		Suicide
	RR†	95% CI	RR	95% CI	RR	95% CI	RR	95% CI
*For states implementing the law during the period 1979–98.
†Regression derived rate ratio of mortality rate with the law to mortality rate without the law.
‡p Value for age-law interaction.
Firearm deaths
<20 years	0.92	0.80–1.06	0.94	0.80–1.06	0.91	0.72–1.15	0.93	0.77–1.12
⩾20 years	0.99	0.93–1.06	1.02	0.96–1.08	1.08	0.89–1.31	0.99	0.88–1.13
p Value‡	0.22		0.62		0.10		0.95
All deaths
<20 years	0.92	0.81–1.05	1.10	0.94–1.29	0.98	0.79–1.20	1.15	0.93–1.42
⩾20 years	1.01	0.95–1.06	1.04	0.99–1.10	1.03	0.88–1.20	1.04	0.95–1.13
p Value‡	0.39		0.12		0.43		0.21