| All | Boys | Girls |  |
---|---|---|---|---|
 | n (%, CI) | n (%, CI) | n (%, CI)) | Significance |
Gambling frequency, past-year (n=956) |  |  |  | Chi=77.263, df=3, p≤0.001 |
 No gambling | 463 (48.4±3.1) | 185 (37.4±4.3) | 278 (60.2±4.5) |  |
 Once or twice | 298 (31.2±2.9) | 160 (32.4±4.1) | 138 (29.9±4.2) |  |
 Sometimes | 167 (17.5±2.4) | 123 (24.9±3.8) | 44 (9.5±2.7) |  |
 Often | 28 (2.9±1.1) | 26 (5.3±2.0) | 2 (0.4±0.6) |  |
Past-year at-risk/problem gambling (DSM- IV-MR-J) (n=956) |  |  |  | Chi=40.892, df=1, p≤0.001 |
 At-risk/problem gambling (score ≥2) | 76 (7.9±1.7) | 66 (13.4±3.0) | 10 (2.2±1.3) |  |
 No gambling or no risk/problem (score 0–1) | 880 (92.1±1.7) | 428 (86.6±3.0) | 452 (97.8±1.3) |  |
Smoking (n=946) | Â | Â | Â | Chi=4.512, df=1, p=0.041 |
 Yes | 76 (8.0±1.7) | 48 (9.9±2.7) | 28 (6.1±2.2) |  |
 No | 870 (92.0±1.7) | 439 (90.1±2.7) | 431 (93.9±2.2) |  |
Drinking for intoxication (n=949) | Â | Â | Â | Chi=2.298, df=1, p=0.138 |
 Yes | 84 (8.9±1.8) | 50 (10.2±2.7) | 34 (7.4±2.4) |  |
 No | 865 (91.1±1.8) | 440 (89.8±2.7) | 425 (92.6±2.4) |  |