Table 4.

Results from nonparametric bootstrap linear regression analyses predicting Timed IADL for the SKILL and ACTIVE dataset.

Study	Predictor	$b_{bc}^{\ast }$	95% CI	p	VIFbc	95% CI
SKILL	Subtest 1	.05	[−.03, .15]	.210	1.21	[1.13, 1.32]
	Subtest 2	.23	[.11, .34]	< .001	1.65	[1.50, 1.83]
	Subtest 3	.21	[.13, .30]	< .001	1.80	[1.66, 1.94]
	Subtest 4	.04	[−.03, .09]	.238	1.34	[1.27, 1.41]
ACTIVE	Subtest 1	.09	[.03, .14]	.001	1.25	[1.20, 1.30]
	Subtest 2	.20	[.14, .25]	< .001	1.62	[1.54, 1.71]
	Subtest 3	.18	[.13, .23]	< .001	1.80	[1.72, 1.87]
	Subtest 4	.05	[.01, .09]	.013	1.37	[1.33, 1.41]

Note. In the SKILL study (n = 828) UFOV subtests accounted for $R_{bc}^2=.19$, 95% CI [.13, .24], p < .001, of Timed IADL variance and in the ACTIVE study (n = 2426) for $R_{bc}^2=.16$, 95% CI [.13, .19], p< .001, of Timed IADL variance. All estimates are based on 10,000 bootstrap samples, bias-corrected (bc) and we computed 95%-confidence intervals using the bias-corrected and accelerated (BCa) method. Regression coefficients $b_{bc}^{\ast }$ are standardized and we report Variance Inflation Factors (VIF) as measures of collinearity. UFOV = Useful Field of View; Timed IADL = Timed Instrumental Activities of Daily Living.