Table 2 Descriptive statistics for substance use indicators, stratified by gender
Substance use indicator | Boys | Girls | χ2 | p |
|---|---|---|---|---|
Alcohol age of initiation | 16.865 | < 0.001 | ||
 Never | 18% | 20.8% | ||
 ≥ 13 years old | 29.9% | 20.8% | ||
 < 13 years old | 52.1% | 58.5% | ||
Drunkenness age of initiation | 6.934 | 0.031 | ||
 Never | 62.4% | 68% | ||
 ≥ 13 years old | 34% | 30% | ||
 < 13 years old | 3.4% | 2% | ||
Smoking age of initiation | 1.915 | 0.384 | ||
 Never | 62.4% | 58.4% | ||
 ≥ 13 years old | 34% | 33.1% | ||
 < 13 years old | 3.4% | 7.6% | ||
Cannabis lifetime | 23.04 | 0.002 | ||
 Never | 84.4% | 90.8% | ||
 Once or twice | 6.3% | 4.6% | ||
 3–5 times | 2.5% | 0.8% | ||
 6–9 times | 0.9% | 0.8% | ||
 10–19 times | 1.6% | 0.9% | ||
 20–39 times | 0.4% | 0.6% | ||
 40 times or more | 2.9% | 0.8% | ||
Alcohol past 30-day use | 47.962 | < 0.001 | ||
 Never | 46.5% | 49.9% | ||
 Once or twice | 26.9% | 35.1% | ||
 3–5 times | 12.4% | 9.7% | ||
 6–9 times | 5.75 | 2.3% | ||
 10–19 times | 4.3% | 1.6% | ||
 20–39 times | 0.9% | – | ||
 40 times or more | 1.5% | 0.5% | ||
Drunkenness past 30-day | 11.130 | 0.133 | ||
 Never | 85% | 88.9% | ||
 Once or twice | 9.1% | 7.9% | ||
 3–5 times | 1.9% | 0.95 | ||
 6–9 times | 0.4% | 0.5% | ||
 10–19 times | 0.6% | 0.2% | ||
 20–39 times | 0.3% | 0.2% | ||
 40 times or more | 0.9% | 0.1% | ||
Smoking past 30-day | 9.112 | 0.245 | ||
 Never | 79.4% | 80.6% | ||
 Once or twice | 6.8% | 7.2% | ||
 3–5 times | 1.6% | 1.8% | ||
 6–9 times | 2.8% | 1.3% | ||
 10–19 times | 2.1% | 2.7% | ||
 20–39 times | 2.25 | 2.5% | ||
 40 times or more | 4.1% | 3.4% | ||