Table 1.
Description of cohort.
| DTR result |
||||
|---|---|---|---|---|
| Dually negative (n = 96,590) | Cocaine positive only (n = 19,139) | Opiate positive only (n = 9042) | Cocaine and opiate positive (n = 15,154) | |
| Gender | ||||
| Men | 72,643 (75) | 16,430 (86) | 7046 (78) | 11,454 (76) |
| Women | 23,947 (25) | 2709 (14) | 1996 (22) | 3700 (24) |
| Mean age at test (±SD) | 29.3 (±10.3) | 29.4 (±8.8) | 32.6 (±8.4) | 32.9 (±7.9) |
| Ethnicity reported at index test | ||||
| White ethnic groups | 68,232 (76) | 15,078 (82) | 7250 (87) | 11,798 (83) |
| Non white ethnic groups | 21,904 (24) | 3293 (18) | 1061 (13) | 2380 (17) |
| Index test following arrest for ‘trigger’ offence | ||||
| Yes | 89,755 (93) | 17,499 (91) | 8481 (94) | 13,991 (92) |
| No | 6835 (7) | 1640 (9) | 561 (6) | 1163 (8) |
| Number of people with a crime over follow-up | ||||
| Men (% of all men) | 43,076 (59) | 8782 (53) | 4794 (68) | 7949 (69) |
| Women (% of all women) | 9556 (40) | 1336 (49) | 1240 (62) | 2562 (69) |
| Number of crimes | ||||
| Men | 194,195 | 39,053 | 26,990 | 45,976 |
| Women | 30,145 | 5827 | 6715 | 15,944 |
| Mean number of crimes (±SD) | ||||
| Men | 2.67 (±4.38) | 2.38 (±4.01) | 3.83 (±5.14) | 4.01 (±5.25) |
| Women | 1.26 (±3.20) | 2.15 (±4.05) | 3.36 (±5.08) | 4.31 (±5.77) |
| Person years of follow-up | ||||
| Men | 145,286 | 32,860 | 14,092 | 22,908 |
| Women | 47,894 | 5418 | 3992 | 7400 |
| Mean estimated incarceration time (years) over 2 year history (±SD) | ||||
| Men | 0.125 (±0.265) | 0.145 (±0.289) | 0.181 (±0.317) | 0.195 (±0.318) |
| Women | 0.032 (±0.118) | 0.074 (±0.182) | 0.098 (±0.208) | 0.110 (±0.192) |
Numbers in round brackets are percentages, unless otherwise stated.