Table 1.
Socio‐demographic and diagnostic characteristics of the study sample
| Measurements | Patients (n = 29) | Healthy controls (n = 20) | Between‐group statistics |
|---|---|---|---|
| Age (years), mean (SD) | 41.5 (6.1) | 40.3 (10.9) | T(48) = 0.506 |
| P = 0.615 | |||
| Gender (women/men) | 8/21 | 6/14 | χ 2 = 0.034 |
| P = 0.854 | |||
| Employment (yes/no) | 13/16 | 20/0 | χ 2 = 16.385 |
| P = 0.00005 | |||
| Daily heroin dose (mg/day), mean (SD) | 323.5 (133.3) | – | – |
| Duration of dependence (years), mean (SD) | 20.6 (7.2) | – | – |
| Age at the first‐time heroin use (years), mean (SD) | 18.3 (4.8) | – | – |
| Duration of opioid maintenance (years), mean (SD) | 6.9 (4.5) | – | – |
| Number of cigarettes per day, mean (SD) | 20.76 (9.0) | 11.50 (8.2) | T(48) = 3.664 |
| P = 0.001 | |||
| Cannabis abuse, (yes/no) | 9/20 | 5/15 | χ 2 = 0.211 |
| P = 0.646 | |||
| Cocaine abuse, (yes/no) | 15/14 | 0/20 | χ 2 = 14.909 |
| P = 0.0001 | |||
| BIS total score, mean (SD) | 65.93 (6.9) | 61.15 (5.6) | T(47) = 2.568 |
| P = 0.013 | |||
| BIS first order attention score, mean (SD) | 11.24 (2.0) | 9.10 (1.4) | T(47) = 4.164 |
| P = 0.0001 | |||
| BIS second order attention score, mean (SD) | 16.72 (3.0) | 14.70 (2.1) | T(47) = 2.636 |
| P = 0.011 |
Abbreviations: BIS: Barrett impulsiveness scale; SD: standard deviation.