Table 4.

Results of the paired and independent t tests of the Swedish cohort.

Scale	Mean difference (95% CI)	P-value
Paired t test
2 VMI SS – VMI SS	-5.5 (-9.8, -1.3)	0.01
2 VMI VP – VMI VP	-10.1 (-17.0, -3.2)	<0.01
2 VMI Motor – VMI motor	-5.2 (-11.6, 1.1)	0.1
WISC VI – WPPSI VI	-13.1 (-17.3, -8.8)	<0.001
WISC PI – WPPSI PI	-8.8 (-12.6, -4.9)	<0.001
WISC SI – WPPSI S	10.4 (5.8, 15.6)	<0.001
Independent t test (female – male)
2VMI SS	13.5 (1.6, 25.3)	0.03
2VMI VP	0.03 (-0.4, 0.5)	0.42
2VMI FMC	13.1 (0.5, 25.7)	0.04
WPPSI FSIQ	14.6 (1.6, 27.7)	0.03
WPPSI VI (verbal)	16.0 (1.1, 30.8)	0.04
WPPSI PI (visual)	6.5 (-4.9, 18.0)	0.25
WPPSI SI (speed)	17.2 (-4.9, 27.2)	<0.001
WISC FSIQ	14.1 (4.1, 24.1)	<0.01
WISC VI (verbal)	12.6 (1.7, 23.7)	0.03
WISC PI (visual)	9.8 (0.2, 19.3)	<0.05
WISC SI (speed)	10.7 (-0.7, 22.1)	0.17

Mean differences, 95% confidence interval (CI) and p-values for paired t and independent t tests.