Table 2.
Substance use characteristics prior to study entry
| Substance | Number | Ever used N (%) | Age of first drug use | Any period of regular use^ | Duration (years) of regular use^ |
|---|---|---|---|---|---|
| Alcohol | 99 | 99 (100) | 13.0 (12.0–16.0) | 69/94 (73.4%) | 4.0 (2.0–6.0) |
| Cannabis | 99 | 99 (100) | 14.0 (12.0–15.0) | 88/95 (92.6%) | 7.0 (4.8–12.0) |
| Inhalants | 99 | 36 (36.4) | 15.5 (13.0–19.0) | 9/34 (26.5%) | 1.0 (0.5–2.0) |
| Cocaine | 99 | 92 (92.9) | 17.0 (15.0–19.0) | 51/84 (60.7%) | 2.0 (2.0–5.0) |
| MDMA | 99 | 86 (86.9) | 17.0 (15.0–19.0) | 39/81 (48.1%) | 2.0 (1.0–3.0) |
| Opioids | 99 | 75 (77.3) | 17.0 (16.0–21.0) | 43/70 (61.4%) | 2.0 (1.0–5.0) |
| Methamphetamine | 99 | 82 (82.8) | 18.5 (15.0–21.0) | 56/78 (71.8%) | 4.0 (1.0–7.1) |
Median (interquartile range) reported for continuous variables. Proportion (n, %) reported for categorical variables
^Regular use defined as using three or more days per week