Age at first use, y Mean ± SD (range) | 33.4 ± 10.2 (19–78) n = 84 | 32.7 ± 10.8 (14–70) n = 68 | 33.2 ± 10.9 (14–70) n = 80 | 23.6 ± 6.7 (16–39) n = 19 |
Duration of regular use, y Mean ± SD (range) | 2.2 ± 1.7 (0.1–8) n = 83 | 5.0 ± 5.4 (0.2–24) n = 68 | 6.0 ± 5.5 (0.1–24) n = 78 | 5.6 ± 5.4 (1–25) n = 19 |
Oxycodone equivalents† of average amount used per day, mg Mean ± SD (range) | 398.0 ± 310.2 (20–1625) n = 84 | 101.4 ± 80.5 (15–480) n = 59 | 158.9 ± 154.0 (15–700) n = 71 | - |
Oxycodone equivalents† of heaviest amount used per day, mg Mean ± SD (range) | 485.1 ± 365.7 (20–1625) n = 84 | 123.1 ± 82.7 (15–480) n = 56 | 211 ± 248.1 (15–1000) n = 71 | - |
Current mode of use, % |
• Oral | 73.8 (chewing) n = 84 | 100 n = 67 | 75.9 n = 79 | 16.7 (smoking) n = 18 |
• Injection | 13.1 n = 84 | 0 n = 67 | 22.8 n = 79 | 77.8 n = 18 |
• Snorting | 13.1 n = 84 | 0 n = 67 | 1.3 n = 79 | 5.6 n = 18 |