Mixed Model Analyses for Cognitive Performance Using a Continuous ED Measure, Including Demographic and Health Variables

Parameter	Age		ED		AFQT		Cholesterol		Pack Years		Depression
	β (SE)	p	β (SE)	p	β (SE)	p	β (SE)	p	β (SE)	p	β (SE)	p
Processing Speedab	−.12 (.03)	<.001	.09 (.03)	.001	.16 (.03)	<.001	ns	ns	−.07 (.03)	.01	ns	ns
ST Memoryb	−.08 (.03)	.01	.09 (.03)	.004	.18 (.03)	<.001	−.16 (.07)	.03	ns	ns	ns	ns
Verbal Ability	ns	ns	.07 (.03)	.05	.48 (.04)	<.001	ns	ns	ns	ns	ns	ns
Verbal Memory	−.06 (.03)	.047	ns	ns	.19 (.03)	<.001	ns	ns	ns	ns	ns	ns
VSP Memoryb	−.1 (.03)	.005	.09 (.03)	.004	.23 (.03)	<.001	ns	ns	ns	ns	ns	ns
Abstract Reasoning	−.14 (.04)	<.001	ns	ns	.47 (.04)	<.001	ns	ns	ns	ns	ns	ns
Working Memoryb	ns	ns	.07 (.06)	.005	.18 (.03)	<.001	ns	ns	ns	ns	ns	ns
Verbal Fluencyb	−.16 (.04)	<.001	.09 (.04)	.01	.18 (.04)	<.001	−.22 (.09)	.01	ns	ns	ns	ns
Set-Shiftinga	ns	ns	ns	ns	.26 (.04)	<.001	ns	ns	ns	ns	ns	ns
Inhibition	ns	ns	ns	ns	ns	ns	ns	ns	ns	ns	.12 (.05)	.008

Note. Presented estimates and significance levels represent each parameter’s influence after all other terms have been entered into the equation. Results are Type III Fixed Effects and are controlled for correlated variance of twin data. Hypertension and BMI were also included in the model, but because they produced no significant Type III Fixed Effects, they have been excluded from the table. AFQT is an index of premorbid cognitive ability at military induction. ST memory = short term memory; VSP Memory = visual-spatial memory; BMI = body mass index; Ns = non-significant Type III Fixed Effects.

^aTime scores were reverse-coded so that higher scores indicate better performance on all measures.

^bRemained significant after FDR.