Failed in an exam before

Yes

N = 114 F (%)

No

N = 636 F (%)

Total %

P value

THC (%)

9 (7.89)

12 (1.89)

1.19

0.003*

Tramadol (%)

7 (6.1)

6 (0.94)

1

0.001*

Opium (%)

2 (1.8)

2 (0.31)

0.2

0.17

BDZs (%)

3 (2.63)

2 (0.31)

0.39

0.001*

Barbiturates (%)

3 (2.63)

0.00

0.39

0.001*

All drugs

24 (21.05)

21 (3.3)

3.17

<0.0001*