Table 4.

Predictors of QOL from Fully Adjusted Regression Analyses

Variables	EQ-5D (n=368) (Model R2 = 0.33)			QWB (n=369) (Model R2 = 0.28)			VAS (n=362) (Model R2 = 0.17)			QOL-AD (n=367) (Model R2 = 0.42)
	β	P	R2*	β	P	R2*	β	P	R2*	β	P	R2*
Age	−0.011	0.007	0.01	−0.005	0.299	0.00	−0.001	0.923	0.00	−0.220	0.173	0.00
Sex (Male)	0.050	< 0.0001	0.02	−0.018	0.275	0.01	0.001	0.944	0.00	1.033	0.037	0.00
Education		0.468	0.00		0.355	0.00		0.243	0.01		0.161	0.01
Marital Status	0.040	0.013	0.00	0.018	0.363	0.00	0.022	0.278	0.00	0.762	0.221	0.00
First Language	0.001	0.942	0.00	−0.023	0.243	0.00	0.009	0.673	0.00	0.790	0.203	0.01
Charlson Score		0.694	0.00		0.584	0.01		0.224	0.01		0.214	0.01
ADAS (Cognition)	−0.003	0.658	0.00	0.004	0.645	0.00	−0.021	0.021	0.01	−0.452	0.100	0.01
DAD (Function)	−0.011	0.158	0.00	−0.016	0.090	0.01	0.003	0.764	0.00	0.168	0.574	0.01
NPI (Behavior)	−0.012	0.071	0.01	−0.013	0.118	0.01	0.004	0.625	0.00	−0.803	0.002	0.04
GDS (Depression)	−0.068	< 0.0001	0.25	−0.066	< 0.0001	0.17	−0.048	< 0.0001	0.10	−2.825	< 0.0001	0.28
Study Center		0.382	0.02		0.006	0.06		0.107	0.04		0.002	0.06

EQ-5D = European Quality of Life-5 Dimensions; QWB = Quality of Well-Being Index; VAS = global quality of life Visual Analog Scale; QOL-AD = Quality of Life-Alzheimer’s Disease; β = β-coefficient; P = P-value; R²* = LMG R², the average of R² increments from adding the variable to models without the variable, across all of the possible models; Charlson score = measure of comorbidity; ADAS-Cog = Alzheimer’s Disease Assessment Scale-Cognitive sub-scale; DAD = Disability Assessment for Dementia; NPI = Neuropsychiatric Inventory; GDS = Geriatric Depression Scale.

All single parameter tests are t-tests with estimated degrees of freedom (df) ranging between 253 and 344. All multiple parameter tests are F-tests and these included: tests for education (numerator df = 2, denominator df > 300), the Charlson comorbidity score (numerator df = 2, denominator df > 300), and study center (numerator df = 9, denominator df > 300).