Table 1.

Model Fit Parameter Estimates for Crude and Sex-Adjusted Negative Binomial Models of Cause-Specific Mortality Trends in the United States From 1999 to 2014

Statistic	Self-Injury	Suicidea	Diabetes	Influenza and Pneumonia	Kidney Disease
Unadjusted model fit
P valueb	.31	.32	.32	.31	.32
AICc	279.33	254.35	298.60	308.77	295.66
Parameter estimates
Year	0.03	0.02	−0.01	−0.03	0.01
SE	0.001	0.001	0.002	0.003	0.003
Wald 95% CI	0.03 to 0.04	0.02 to 0.02	−0.01 to −0.00	−0.03 to −0.02	0 to 0.01
P value	<.001	<.001	.002	<.001	<.001
Rate ratio	1.03	1.02	0.99	0.98	1.01
Dispersion	0.001	0	0.001	0.003	0.002
Sex-adjusted model fit
P value	.26	.30	.29	.27	.28
AICc	532.54	455.15	551.27	570.95	545.35
Parameter estimates
Year	0.05	0.03	−0.02	−0.03	0.01
SE	0.002	0.001	0.002	0.003	0.003
Wald 95% CI	0.05 to 0.06	0.02 to 0.03	−0.02 to −0.01	−0.04 to −0.02	0.00 to 0.01
P value	<.001	<.001	<.001	<.001	.02
Rate ratio	1.05	1.03	0.98	0.97	1.01
Sex (male)	50.42	25.45	−43.12	−23.96	−13.17
SE	5.31	2.80	4.85	8.20	7.39
Wald 95% CI	40.02 to 60.82	19.96 to 30.95	−52.63 to −33.61	−40.02 to −7.90	27.65 to 1.32
P value	<.001	<.001	<.001	.003	.07
Rate ratio	0	0	0	0	0
Year × sex (male)	−0.03	−0.01	0.02	0.01	0.01
SE	0.003	0.001	0.002	0.004	0.004
Wald 95% CI	−0.03 to −0.02	−0.02 to −0.01	0.02 to 0.03	0.01 to 0.02	0 to 0.01
P value	<.001	<.001	<.001	.004	.07
Rate ratio	0.98	0.99	1.02	1.01	1.01
Dispersion	0.001	0	0.001	0.003	0.002

Abbreviation: AIC, Akaike information criterion.

^aSuicide is a component of self-injury, together with estimated deaths from drug self-intoxication. See results of the sensitivity analysis.

^bP values calculated with Pearson χ² test.

^cThe Akaike information criterion estimates the relative quality of statistical models for a given set of data. Lower values indicate better quality.