Characteristics of the study sample
| Variables | Categories | N (%) |
| Gender | Females | 7940 (50.9) |
| Males | 7662 (49.1) | |
| Age bracket | 14–15 years | 7622 (48.9) |
| 16–17 years | 7980 (51.1) | |
| Gambling | Non-gambler+non-problem gamblers | 14 590 (93.5) |
| At risk+problem gamblers | 1012 (6.5) | |
| Alcohol intake | Never in the last year | 8522 (54.6) |
| At least once last year | 7080 (45.4) | |
| Smoking | Never in the last year | 11 613 (74.4) |
| At least once last year | 3989 (25.6) | |
| Cannabis consumption | Never in the last year | 12 780 (81.9) |
| At least once last year | 2822 (18.1) | |
| Parents’ education | Both with high-school diploma or university degree | 7615 (51.7) |
| At least one with university degree | 712 (4.8) | |
| At least one with high-school diploma | 3477 (23.6) | |
| Both with elementary or middle-school diploma | 2930 (19.9) | |
| Mother’s employment | Not working | 4670 (30.4) |
| Working | 10 717 (69.6) | |
| Father’s employment | Not working | 1119 (7.4) |
| Working | 13 987 (92.6) | |
| Deceased parents | Both parents alive | 15 311 (98.1) |
| At least one deceased parent | 291 (1.9) | |
| Level of economic dissatisfaction | Very satisfied or satisfied | 10 319 (66.1) |
| Neither satisfied nor dissatisfied | 4508 (28.9) | |
| Dissatisfied or very dissatisfied | 775 (5) | |
| Weekly income (€) | 0 | 2882 (18.5) |
| 1–30 | 10 798 (69.2) | |
| 31–100 | 1599 (10.2) | |
| 100 or more | 323 (2.1) | |
| Geographical area | Northern Italy | 6543 (41.9) |
| Central Italy | 2923 (18.7) | |
| Southern Italy and Islands | 6136 (39.3) | |
| Type of school | Grammar school or artistic high school | 8071 (51.7) |
| Technical or vocational school | 7531 (48.3%) |