Table 2.
Sample Characteristics.
| Variable | Entire sample (n = 748) | ID (n = 119) | Non-ID (n = 629) | |
|---|---|---|---|---|
| M (SD)/N (%) | Test statistic | |||
| Age at admission | 32.73 (9.32) | 34.14 (10.54) | 32.46 (9.05) | F(1, 743) = 3.27 |
| Tretament duration | 9.49 (3.82) | 10.66 (4.10) | 9.27 (3.75) | F(1, 738) = 13.39*** |
| Gender (male) | 667 (89.2%) | 106 (89.1%) | 561 (89.2%) | χ2(1) = 0.01 |
| Birthland | ||||
| Netherlands (yes) | 575 (76.9%) | 84 (70.6%) | 491 (78.1%) | χ2(6) = 5.37 |
| Criminal history | ||||
| Moderate violence | 390 (52.1%) | 65 (54.6%) | 325 (51.7%) | χ2(1) = 0.35 |
| Robbery | 210 (28.1%) | 30 (25.2%) | 180 (28.6%) | χ2(1) = 0.58 |
| Manslaughter | 170 (22.7%) | 27 (22.7%) | 143 (22.7%) | χ2(1) = 0.00 |
| Severe violence | 164 (21.9%) | 22 (18.5%) | 142 (22.6%) | χ2(1) = 0.98 |
| Arson | 86 (11.5%) | 17 (14.3%) | 69 (11.1%) | χ2(1) = 1.08 |
| Sexual violence against adults | 85 (11.4%) | 22 (18.5%) | 63 (10.0%) | χ2(1) = 7.13** |
| Murder | 63 (8.4%) | 5 (4.2%) | 58 (9.2%) | χ2(1) = 3.27 |
| Sexual violence against minors | 42 (5.6%) | 13 (10.9%) | 29 (4.6%) | χ2(1) = 7.13** |
| Violent recidivism 2 years after release (yes) | 116 (15.8%) | 13 (11.2%) | 103 (16.4%) | χ2(1) = 2.21 |
Note. Test statistic refers to the test that was used to evaluate differenecs between patients with and without ID. n = number of participants; SD = standard deviation; ID = intellectual disability.
**p < .01. ***p < .001.