Table 1.

Test-retest sample demographics and frequency of completion and integrity failures.

	iPad (N=168)	PC (N=168)	Total	p
Demographics			(N=168)
Age Mean (SD)			64.4 (5.39)
Years of Education Mean (SD)			15.2 (2.27)
Percent Male			52%
Prior Cogstate Visits Mean (SD)			2.35 (1.09)
Completion, n (%) failed			(N=336)
Detection	0 (0.0%)	1 (0.6%)	1 (0.3%)	0.32
Identification	0 (0.0%)	1 (0.6%)	1 (0.3%)	0.32
One Card Learning	1 (0.6%)	2 (1.2%)	3 (0.9%)	0.56
One Back	0 (0.0%)	2 (1.2%)	2 (0.6%)	0.16
Groton Maze Learning Test	0 (0.0%)	1 (0.6%)	1 (0.3%)	0.32
Any completion flag failed	1 (0.6%)	4 (2.4%)	5 (1.5%)	0.18
Integrity, n (%) failed			(N=336)
Detection	6 (3.6%)	2 (1.2%)	8 (2.4%)	0.15
Identification	1 (0.6%)	4 (2.4%)	5 (1.5%)	0.18
One Card Learning	2 (1.2%)	1 (0.6%)	3 (0.9%)	0.56
One Back	2 (1.2%)	1 (0.6%)	3 (0.9%)	0.56
Groton Maze Learning Test	0 (0.0%)	2 (1.2%)	2 (0.6%)	0.16
Any integrity flag failed	11 (6.5%)	9 (5.4%)	20 (6.0%)	0.64

Note. Overall failures were counted once even if more than one portion of Cogstate was failed for that participant’s visit. Thus overall count may differ from the sum of the parts. PC = personal computer; SD = standard deviation. P-values reported above are from linear model ANOVAs (continuous variables) or Pearson’s Chi-square test (frequencies).