Table 4.

Model Fit and Heritability Estimates for the Broader and Broadest Definitions^a of Death due to Infection in Danish Twin Pairs

Definition and Model	a2b		c2c		d2d		e2e		AIC	vs.	Δdff	Δχ2g	P Value
	Heritability	95% CI	Heritability	95% CI	Heritability	95% CI	Heritability	95% CI
Broader
ADE	0.26	0.00, 0.50			0.15	0.00, 0.52	0.59	0.47, 0.71	−5.71
ACE	0.40	0.12, 0.50	0.00	0.00, 0.21			0.60	0.50, 0.72	−5.42
AEh	0.40	0.12, 0.50					0.60	0.50, 0.72	−7.42	ADE	1	0.29	0.59
CE			0.28	0.19, 0.36			0.72	0.64, 0.86	−0.34	ACE	1	7.08	<0.01
E							1.00		31.56	AE	1	40.98	<0.001
Broadest
ADE	0.54	0.48, 0.59			0.00	0.00, 0.05	0.46	0.41, 0.51	17.22
ACEh	0.19	0.03, 0.35	0.29	0.16, 0.41			0.52	0.46, 0.59	−3.752
AE	0.54	0.49, 0.59					0.46	0.41, 0.51	15.22	ACE	1	20.97	<0.001
CE			0.42	0.38, 0.46			0.58	0.54, 0.62	−0.64	ACE	1	5.12	0.02
E							1.00		339.99	AE	1	342.62	<0.001

Abbreviations: AIC, Akaike Information Criterion; CI, confidence interval.

^aThe definitions are categorized as described in the Materials and Methods section of the text and in the Web Appendix, which is posted on the Journal’s website (http://aje.oupjournals.org/).

^bProportion of total variance ascribed to additive genetic effects.

^cProportion of total variance ascribed to common environmental effects.

^dProportion of total variance ascribed to genetic dominance effects.

^eProportion of total variance ascribed to unique environmental effects.

^fDifference in degrees of freedom between models.

^gDifference in twice the log-likelihood between compared models.

^hBest fitting model.