Table 3.

Univariate means and multivariable p-coefficients for cognitive testing by sex-specific quartiles of Kt/V

Cognitive test		Function tested	Univariate means by sex-specific Kt/V quartiles					Multivariable β-coefficients by sex-speci fic Kt/V quartiles
			Kt/V Q1	Kt/V Q2	Kt/V Q3	Kt/V Q4	trend p value	Kt/V Q1	Kt/V Q2	Kt/V Q3	trend p value
MMSE		screen	27.1	26.6	26.9	25.8	0.007	1.03	1.00	1.07	0.056
NAART		intelligence	101.8	103.2	102.5	100.5	0.474	3.21	4.91	1.49	0.051
Percent retention	{	primary cortical (memory)	55.8	52.0	52.9	49.5	0.251	0.17	0.71	1.68	0.983
Recognition		21.0	21.1	21.0	20.0	0.062	0.74	1.43	1.15	0.144
Block design	{	primary subcortical (executive and processing speeds)	26.3	28.0	24.8	26.4	0.604	−1.37	1.84	−0.84	0.771
Digit-symbol coding			42.4	40.1	37.8	40.7	0.440	0.19	1.42	−0.11	0.810
Trails A			58.0	59.4	60.6	64.0	0.368	−2.92	−5.98	−6.16	0.692
Trails B		172.5	177.4	209.4	178.2	0.435	7.63	−9.83	16.42	0.986

Results represent the mean raw score by sex-specific Kt/V quartiles and β-coefficient by sex-specific quartiles. Trails B analyses were performed using Tobit regression to account for failure to complete the task within 5 min. β-Coefficients by sex-specific quartiles are in reference to Kt/V, Q4. Minimum and maximum spKt/V for each quartile by sex – men: Q1 (0.97–1.28), Q2 (1.29–1.41), Q3 (1.42–1.54), Q4 (1.55–1.96); women: Q1 (1.06–1.43), Q2 (1.43–1.58), Q3 (1.58–1.73), Q 4 (1.73–2.56). NAART = North American Adult Reading Test.