Table 4.
Comparison of reporting licit and illicit substance use with self‐reported cannabis use in individuals who had cannabis metabolite THC‐COOH detected in their hair using logistic regression (complete case analysis n = 174).
| Use of other drugs | Self‐reported use (past 3 months) in those with cannabis detected in hair | Total N (%) | OR (95% CI) | P | |
|---|---|---|---|---|---|
| Yes (n = 29) n (%) | No (n = 145) n (%) | ||||
| Alcohol consumption | |||||
| Non‐hazardous | 4 (4.1) | 93 (95.9) | 97 (100) | 0.08 (0.03–0.26) | ≤ 0.001 |
| Hazardous and harmful | 25 (35.5) | 52 (67.5) | 77 (100) | ||
| Tobacco (past 30 days) | |||||
| No | 8 (6.0) | 126 (94.0) | 134 (100) | 0.04 (0.02–0.12) | ≤ 0.001 |
| Yes | 21 (52.5) | 19 (47.5) | 40 (100) | ||
| Serum cotinine (> 10 ng/ml) | |||||
| No | 18 (11.4) | 140 (88.6) | 158 (100) | 0.06 (0.02–0.20) | ≤ 0.001 |
| Yes | 29 (16.7) | 5 (31.30 | 16 (100) | ||
| Other illicit drugs (past 3 months) | |||||
| No | 18 (11.4) | 140 (88.6) | 158 (100) | 0.07 (0.02–0.23) | ≤ 0.001 |
| Yes | 11 (68.8) | 5 (31.2) | 16 (100) | ||
All measures self‐reported apart from serum cotinine levels. Serum cotinine cut‐off level of 10 ng/ml, which is representative of smoking within the past month (i.e. levels higher than that observed from passive smoking). OR = odds ratio; CI = confidence interval.