Table 2.

Model comparisons among alternative latent change score models of domain-specific cognitive performance and IADL functioning: Results from ACTIVE (N=2,802)

Cognitive domain	Model stage	Model description	RMSEA	CFI	Log- likelihood	Number of free parameters	Change in - 2LL (df)
Memory performance
	1	No coupling	0.068	0.931	−29510.602	28	REF
	2	Memory → change IADL	0.069	0.931	−29509.842	29	1.520 (1)
	3	IADL → change Memory	0.068	0.932	−29502.117	29	16.970 (1)
	4	Dual coupling	0.069	0.933	−29500.766	30	19.672 (2)
Reasoning performance
	1	No coupling	0.128	0.835	−27824.813	28	REF
	2	Reasoning → change IADL	0.129	0.834	−27824.74	29	0.146 (1)
	3	IADL → change Reasoning	0.129	0.833	−27708.008	29	233.610 (1)
	4	Dual coupling	0.131	0.832	−27708.008	30	233.610 (2)
Speed of processing performance
	1	No coupling	0.104	0.791	−31149.078	28	REF
	2	Speed → change IADL	0.105	0.79	−31149.069	29	0.018 (1)
	3	IADL → change Speed	0.107	0.781	−31120.467	29	57.222 (1)
	4	Dual coupling	0.109	0.78	−31120.025	30	58.106 (2)

RMSEA: root mean squared error of approximation. CFI: comparative fit index. Df: degrees of freedom.