Table 1 Demographic information about the three samples

N (female)

111 (48)

31 (5)

42 (20)

38 (23)

X²(2) = 14.2

 <0 .001^a

Age (SD)

16.0 (1.3)

16.0 (1.3)

16.0 (1.2)

16.1 (1.3)

F(108) = 0.8

0.923

N with substance use disorders (%)

X² (3) = 2.9

0.816

Alcohol

45 (40.5%)

11 (35.5%)

18 (42.9%)

16 (42.1%)

Cannabis

58 (52.3%)

15 (48.4%)

24 (57.1%)

19 (50.0%)

MDMA

26 (23.4%)

4 (13.0%)

11 (26.2%)

11 (29.0%)

Stimulants

25 (23.4%)

3 (9.7%)

12 (28.6%)

8 (21.1%)

N with psychotic disorders (%)

4 (3%)

0

1 (2%)

3 (8%)

X² (2) = 3.4

0.187

N with anxiety disorders (%)

20 (18%)

2 (6%)

4 (10%)

14 (37%)

X² (2) = 14.0

 < .001^a

N with mood disorders (%)

62 (56%)

15 (48%)

20 (48%)

27 (71%)

X² (2) = 5.4

0.067

N with behavioural disorders (%)

57 (51%)

13 (42%)

19 (45%)

11 (29%)

X² (2) = 2.2

0.341

N with obsessive–compulsive disorder (%)

5 (5%)

0

0

5 (13%)

X² (2) = 10.1

0.007^a