| Variable | Adjusted OR (95% CI) | ||
|---|---|---|---|
| Model 1 | Model 2 | Model 3 | |
| Sex | |||
| Male | 1.07 (0.93–1.23) | 1.08 (0.94–1.24) | 1.09 (0.94–1.25) |
| Female | 1 | 1 | 1 |
| Grade level | |||
| 7 | 0.65 (0.50–0.86) | 1.49 (1.10–2.01) | 1.63 (1.22–2.20) |
| 8 | 0.79 (0.62–1.02) | 1.40 (1.06–1.84) | 1.52 (1.15–2.01) |
| 9 | 0.85 (0.67–1.08) | 1.14 (0.89–1.47) | 1.24 (0.96–1.60) |
| 10 | 0.73 (0.58–0.92) | 0.84 (0.66–1.07) | 0.89 (0.70–1.14) |
| 11 | 0.87 (0.69–1.09) | 0.86 (0.68–1.08) | 0.90 (0.72–1.14) |
| 12 | 1 | 1 | 1 |
| Ethnic origin | |||
| Asian | 0.60 (0.42–0.86) | 0.89 (0.62–1.27) | 0.88 (0.62–1.26) |
| Aboriginal | 1.25 (1.00–1.66) | 1.25 (0.98–1.61) | 1.23 (0.95–1.57) |
| Black | 1.05 (0.68–1.65) | 1.48 (0.93–2.37) | 1.48 (0.93–2.35) |
| Other | 1.01 (0.82–1.25) | 1.32 (1.05–1.66) | 1.30 (1.03–1.64) |
| White | 1 | 1 | 1 |
| Risk-taking behaviours | |||
| Current smoker | 2.01 (1.54–2.64) | 1.51 (1.18–1.94) | 1.52 (1.19–1.95) |
| Nonsmoker | 1 | 1 | 1 |
| Heavy drinking | 3.40 (2.83–4.08) | 3.41 (2.84–4.09) | |
| No drinking | 0.26 (0.21–0.32) | 0.25 (0.21–0.30) | |
| Light drinking | 1 | 1 | 1 |
| Marijuana use | 4.49 (3.80–5.31) | 2.30 (1.91–2.77) | 2.29 (1.90–2.76) |
| No marijuana use | 1 | 1 | 1 |
| Individual school measures | |||
| Grade average ≥ 70% | 0.76 (0.65–0.89) | 0.79 (0.67–0.93) | 0.80 (0.68–0.94) |
| Grade average < 70% | 1 | 1 | 1 |
| School connectedness | 0.94 (0.92–0.96) | 0.95 (0.93–0.97) | 0.96 (0.93–0.98) |
| Absence from school ≥ 3 days | 2.70 (2.16–3.37) | 2.00 (1.56–2.57) | 2.06 (1.60–2.65) |
| Absence from school 1–2 days | 1.66 (1.36–2.02) | 1.24 (1.03–1.50) | 1.26 (1.04–1.52) |
| No absence from school | 1 | 1 | 1 |
| School team sports | 1.29 (1.12–1.48) | 1.17 (1.01–1.35) | 1.16 (1.01–1.34) |
| No school team sports | 1 | 1 | 1 |
| Weekly spending money | |||
| ≥ $40 | 1.51 (1.26–1.79) | 1.51 (1.26–1.79) | 1.51 (1.27–1.80) |
| Unknown | 1.14 (0.88–1.47) | 1.07 (0.85–1.35) | 1.06 (0.84–1.34) |
| < 40 | 1 | 1 | 1 |
| Province of residence | |||
| Newfoundland and Labrador | 0.82 (0.71–0.95) | ||
| Prince Edward Island | 0.66 (0.56–0.78) | ||
| Quebec | 0.70 (0.57–0.86) | ||
| Ontario | 0.87 (0.75–1.00) | ||
| Manitoba | 0.65 (0.57–0.76) | ||
| Saskatchewan | 0.64 (0.52–0.78) | ||
| Alberta | 0.98 (0.78–1.22) | ||
| British Columbia | 0.96 (0.80–1.15) | ||
| Nova Scotia | 1 | ||
| Observations | 36 709 | 36 155 | 36 155 |
Note: CI = confidence interval, OR = odds ratio. *Model 1 included all covariates with the exception of heavy drinking and province of residence. Model 2 added heavy drinking to the analysis, and model 3 added province of residence.