|  | Age of menarche (years) | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |  | Online (%) | Paper (%) | Total (%) | |||||||||
 |  | n | ≤ 12 | ≥ 13 | P | n | ≤ 12 | ≥ 13 | P | n | ≤ 12 | ≥ 13 | P¥ |
 | drank alcohol | 812 | 46.9 | 38.5 | * | 572 | 59.8 | 47.4 | ** | 1384 | 51.5 | 42.6 | *** |
Before age | was drunk | 820 | 25.7 | 19.0 | * | 572 | 36.2 | 26.7 | * | 1392 | 29.4 | 22.5 | ** |
14 years, | took drugs | 806 | 5.9 | 3.3 | 0.071 | 559 | 8.7 | 2.9 | ** | 1365 | 6.9 | 3.1 | ** |
 | smoked | 822 | 29.0 | 22.6 | * | 570 | 29.3 | 22.4 | 0.065 | 1392 | 29.1 | 22.5 | ** |
 | had sex | 820 | 32.8 | 22.4 | *** | 554 | 35.0 | 23.1 | * | 1374 | 33.5 | 22.7 | *** |
Before age 16 years, | had unprotected sex | 820 | 13.4 | 11.0 | 0.286 | 563 | 13.5 | 7.3 | * | 1383 | 13.4 | 9.3 | * |
 | first pregnant | 822 | 1.0 | 1.0 | 1.000 | 578 | 1.3 | 0.6 | 0.341 | 1400 | 1.1 | 0.8 | 0.763 |
 | had an abortion | 822 | 12.4 | 13.1 | 0.754 | 578 | 7.9 | 6.6 | 0.529 | 1400 | 10.8 | 10.1 | 0.986 |
∫Took drugs/alcohol at first sex | 785 | 28.4 | 28.4 | 0.991 | 509 | 28.8 | 20.6 | * | 1294 | 28.5 | 25.0 | 0.234 | |
$Typical | aggression | 142 | 19.0 | 15.7 | 0.324 | 93 | 16.0 | 17.6 | 0.428 | 235 | 18.0 | 16.6 | 0.782 |
reactions to | ignoring people | 226 | 25.9 | 29.5 | Â | 153 | 31.0 | 25.9 | Â | 379 | 27.6 | 27.9 | Â |
emotional upset | moodiness | 449 | 55.1 | 54.8 | Â | 303 | 53.1 | 56.5 | Â | 752 | 54.4 | 55.6 | Â |
Bullying | victim | 820 | 63.4 | 56.1 | * | 573 | 50.0 | 46.1 | 0.362 | 1393 | 58.6 | 51.5 | * |
 | perpetrator | 822 | 18.0 | 19.2 | 0.654 | 564 | 17.4 | 12.4 | 0.094 | 1386 | 17.8 | 16.1 | 0.580 |
§Frequency | Never | 607 | 71.6 | 76.8 | 0.392 | 448 | 74.0 | 80.2 | 0.108 | 1055 | 72.5 | 78.4 | * |
of | <1/year | 138 | 19.3 | 14.4 | Â | 64 | 12.8 | 10.0 | Â | 202 | 17.0 | 12.4 | Â |
involvement | circa 1/year | 47 | 6.4 | 5.1 | Â | 38 | 7.9 | 5.7 | Â | 85 | 6.9 | 5.4 | Â |
in fighting | >1/year | 26 | 2.7 | 3.7 | Â | 26 | 5.3 | 4.0 | Â | 52 | 3.6 | 3.8 | Â |
Time off | ≤ 10 days | 672 | 78.0 | 86.7 | ** | 450 | 73.5 | 84.3 | ** | 1122 | 76.4 | 85.6 | *** |
school/year | ≥ 11 days | 144 | 22.0 | 13.3 |  | 112 | 26.5 | 15.7 |  | 256 | 23.6 | 14.4 |  |