From: Difference in long-term relapse rates between youths with ketamine use and those with stimulants use
 | Ketamine group (N = 92) | Stimulants group (N = 43) | Statistic | P-value |
---|---|---|---|---|
Age (years) | ||||
 Range | 13–17 | 12–17 |  |  |
 Mean (SD) | 16.0 (1.0) | 16.1 (1.1) | t = 0.669 | 0.505 |
Gender |  |  | χ2 = 0.003 | 0.956 |
 Female | 21 (22.8) | 10 (23.3) |  |  |
 Male | 71 (77.2) | 23 (76.7) |  |  |
Previous conviction record at baseline |  |  | χ2 = 0.181 | 0.670 |
 Without | 63 (68.5) | 31 (72.1) |  |  |
 With | 29 (31.5) | 12 (27.9) |  |  |
Academic or social status at baseline |  |  | χ2 = 8246 | 0.016* |
 Attending school | 36 (39.1) | 7 (16.3) |  |  |
 Employed | 28 (30.4) | 22 (51.2) |  |  |
 Dropout and unemployed | 28 (30.4) | 14 (32.6) |  |  |
Family status |  |  | χ2 = 0.545 | 0.761 |
 Double-parent families | 42 (45.7) | 19 (44.2) |  |  |
 Single-parent families | 38 (41.3) | 20 (46.5) |  |  |
 Grandparent(s) | 12 (13.0) | 4 (9.3) |  |  |