TABLE 1.
Sample characteristics.
| Active group (N = 40) | Sham group (N = 40) | Statistic | |
| Age [mean (SD)] | 44.95 (10.03) | 43.75 (11.41) | t(78) = 1.498, p = 0.619 |
| Gender (man: woman) | 29: 11 | 31: 9 | X2(1) = 0.267, p = 0.606 |
| IQ [median (range)] | 83 (47–97) | 84 (42–100) | U = 772.500, p = 0.791 |
| Years of education [mean (SD)] | 7.5 (3.44) | 7.238 (3.61) | t(78) = 0.333, p = 0.740 |
| Handedness (right: left) | 37: 3 | 38: 2 | p = 1.000, Fisher’s exact test |
| MoCA score (>27: 18–26) | 26: 13 | 30: 10 | X2(1) = 0.664, p = 0.415 |
| PTSD (yes: no) | 5: 35 | 6: 34 | X2(1) = 0.105, p = 0.745 |
| Cocaine dependence (yes: no) | 9: 31 | 5: 35 | X2(1) = 1.385, p = 0.239 |
| Cannabis dependence (yes: no) | 8: 32 | 8: 32 | X2(1) = 0.000, p = 1.00 |
| Duration of problematic alcohol use in years [mean (range)] | 11 (2–36) | 10 (1–36) | U = 652.500, p = 0.211 |
| Number of DSM-IV criteria fulfilled [median (range)] | 9 (3–11) | 9 (4–11) | U = 775.000, p = 0.808 |
| Anti-craving medication (yes: no) | 15: 25 | 12: 28 | X2(1) = 0.503, p = 0.478 |
| Anti-depressant medication (yes: no) | 15: 25 | 7: 33 | X2(1) = 4.013, p = 0.045 |
| Sedative medication (yes: no) | 3: 37 | 1: 39 | p = 0.615, Fisher’s exact test |
| BIS score [mean (SD)] | 69.53 (8.72) | 69.58 (9.42) | t(78) = −0.025, p = 0.980 |
| UPPS score [mean (SD)] | 108.60 (14.40) | 110.65 (16.00) | t(78) = −0.602, p = 0.549 |
No significant differences were found between the active and sham group on any of the characteristics, except for the use of anti-depressant medication. Depending on whether the outcome measure was continuous or categorical, and whether it was normally distributed, two sample T-test, Mann–Whitney-U test, Chi–square tests or Fisher’s exact test were used. P-values < 0.05 were considered significant. Abbreviations: SD = standard deviation; PTSD = post-traumatic stress disorder; DSM-IV: diagnostic and statistical manual of mental disorders version 4; BIS = barratt impulsiveness scale; UPPS = urgency, premeditation, perseverance, sensation seeking impulsive behavior scale.