. Author manuscript; available in PMC: 2009 Jun 1.

Published in final edited form as: Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2008 Nov 3;16(3):241–259. doi: 10.1080/13825580802438868

Table 2.

Dual Task Costs (DTCs) For Young And Older Adults comparing Dual Task Language Samples to Baseline Language Samples. ^* Mark DTCs Significantly Different From Zero. Correlations between the Baseline Language Sample Measures and those obtained from the Dual Task Sample are Reported Separately for Young and Older Adults.

Dual Task Costs
								Correlation with Baseline
	Young Adults		Older Adults
					F (1, 77)	p	p_rep
	M	SD	M	SD				Young Adults	Older Adults
Fluency
MLU	+10.4^*	2.4	− 0.4	1.6	1.094	=.299	.645	.58^**	.52^**
% w/ fillers	+64.4^*	8.4	+ 1.6	0.4	47.923	<.001	.999	.64^**	.04
fillers/utterance	+74.1^*	24.4	+ 0.6	0.3	58.476	<.001	.999	.64^**	.16
% Grammatical	+0.5	0.2	+ 0.4	0.3	< 1.0	> .50	.013	.10	.09
WPM	+16.6^*	12.4	+26.15^*	8.1	7.819	=.007	.959	.77^**	.32^*

Grammatical Complexity
MCU	+52.5^*	24.1	+ 2.7	6.1	24.344	<.001	.999	.54^**	.65^**
DLevel	+40.3^*	21.1	+ 2.1	3.2	20.486	<.001	.999	.63^**	.67^**

Content
TTR	+ 1.1	2.3	+ 1.0	1.1	< 1.0	>.50	.432	.15	.17
PDensity	−10.2^*	2.4	+ 3.1	4.2	6.685	=.011	.947	.56^**	.68^**

p < .05, p_rep ≥ .980

^**

p < .01, p_rep ≥ .995

Note: MLU = mean length of utterance; fillers/utterance = number of fillers per utterance; % w/fillers = percentage of sentences with fillers; % Grammatical = percentage of grammatical sentences; WPM = words per minute; MCU = mean clauses per utterance; DLevel = developmental level; TTR = type-token ratio; PDensity = propositional density.