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* |