Table 1. Demographic and Substance Use Measures.
| Controls (n=21) | Cannabis (n=21) | p-value | |
|---|---|---|---|
| Demographics, mean (SD) | |||
| Age (years) | 31.0 (11.7) | 36.5 (8.8) | 0.10 |
| Gender (M/F) | 11/10 | 10/11 | 0.76 |
| WASI FSIQ | 111.8 (9.7) | 106.7 (10.9) | 0.12 |
| Substance use, median (range) | |||
| Lifetime cumulative dose (number of joints) | 2 (0–60) | 26 711 (4512–79 200) | |
| Age of onset, regular use (years) | n/a | 16 (12–25) | |
| Duration of regular use (years) | 0 | 20 (10–38) | |
| Urinary carboxy-THC:creatinine ratio (ng/mg) | 0 | 410 (0–2568) | |
| Salivary delta-9-THC (ng/ml) | 0 | 1.7 (0–11) | |
| Withdrawal (MWCL score) | 0 | 3 (0–17) | |
| Severity of dependence (SDS score) | 0 | 5 (0–14) | |
| Tobacco cigarettes (no. per day) | 0 (0–15) | 5 (0–30) | < 0.001 |
| Alcohol consumption (drinks per month) | 10.5 (0–100) | 5.25 (0–55) | 0.41 |
Abbreviations: MWCL, Marijuana Withdrawal Checklist; THC, tetrahydrocannabinol; WASI, Wechsler-Abbreviated Scale of Intelligence.