Table 1 Demographic and clinical characteristics at baseline exam, for the full sample and for the two subgroups (those who either failed or passed the scopolamine challenge test (SCT) at their baseline exams)

N (%)

N (%)

N (%)

p

Cohen’s d

Sex

No. of female

38 (60%)

20 (71%)

18 (60%)

.296

–

APOE

No. of ε4 carriers

30 (48%)

17 (58%)

13 (43%)

.559

–

Mean (SD)

Mean (SD)

Mean (SD)

p

Age

No. of years

63.06 (5.42)

63.93 (6.31)

62.44 (5.04)

.349

0.28

Education

No. of years

17.21 (2.77)

17.47 (3.46)

17.14 (2.55)

.689

0.12

SUVr (neocortex)

Standardized uptake value ratio

1.023 (0.19)

1.10 (0.24)

0.95 (0.09)

.000

2.47

SUVr (anterior cingulate)

Standardized uptake value ratio

1.064 (0.22)

1.197 (0.27)

0.984 (0.10)

.000

2.95

GDS

Total score

1.86 (2.16)

1.60 (1.45)

1.94 (2.35)

.602

− 0.16

DASS Depression Subscale

Total Depression Subscale Score

3.56 (6.70)

2.60 (2.59)

3.87 (7.56)

.526

− 0.19

DASS Anxiety Subscale

Total Anxiety Subscale Score

2.73 (4.53)

2.40 (3.58)

2.83 (4.83)

.752

− 0.09

DASS Stress Subscale

Total Stress Subscale Score

6.73 (6.77)

6.67 (4.55)

6.74 (7.38)

.969

− 0.01

MAC-Q

Total score

21.80 (3.57)

21.35 (3.94)

21.28 (3.27)

.501

0.15

Body mass index

Body mass index

26.69 (5.50)

28.66 (7.95)

26.07 (4.41)

.113

0.48

MMSE

Total score

29.05 (1.02)

28.93 (1.16)

29.08 (0.99)

.624

− 0.15

GMLT Moves/Second (MPS)

Total correct moves/second

0.81 (0.20)

0.78 (0.20)

0.81 (0.19)

.573

− 0.17

GMLT Total Errors (TER)

Total no. of errors

55.60 (14.38)

53.21 (16.21)

52.79 (14.80)

.430

− 0.22

GMLT Composite

Standardized z-score

− 0.02 (0.81)

− 0.08 (0.89)

− 0.01 (0.79)

.764

− 0.09

ISLT Total Recall

Total words recalled (three learning trials)

25.62 (4.20)

24.04 (4.41)

27.85 (4.16)

.368

− 0.28

One Card Learning task

Accuracy of performance

1.01 (0.10)

1.05 (0.03)

1.10 (0.10)

.085

− 0.40

One Back task

Accuracy of performance

1.45 (0.11)

1.40 (0.14)

1.46 (0.10)

.063

− 0.54