Table 2.

Demographic data and neuropsychological test results for PiB‐negative and PiB‐positive Down's syndrome groups

	TD controls	PiB –ve	PiB +ve	Effect size	p
Number	20	19	15	–	–
Gender (% female)	45	57	46.67	χ2 = 0.740	.691
Age	43.5	41.0	48.0**	χ2 = 10.074	.006
Age range	30–55	30–48	39–55	–	–
DVARS	25.5	31.87*	37.85*	χ2 = 26.467	<.0005
FD	0.17	0.34*	0.39*	χ2 = 24.512	<.0005
Raw IQ	–	56	60	U = 107.5	.482
Tower of London	–	9	6.5	U = 64.5	.018
New learning	–	14	9	U = 70.5	.011
Language	–	15	15	U = 97	.111
Number with dementia	–	3	5	–	–

FD, Frame‐wise displacement; IQ, intelligence quotient; PiB –ve, PiB‐negative; PiB +ve, PiB‐positive; D, typically developing.

^* Significantly different from controls at the level of p < .0005

^** Significantly different from PiB‐negative Down's syndrome at the level of p < .005.