Sociodemographic and clinical characteristics of the study sample by group
| Group; mean ± SD or no. (%) | |||
|---|---|---|---|
| Characteristic | NSSI, n = 30 | Control, n = 30 | p value* |
| Age, yr | 15.27 ± 1.36 | 15.27 ± 1.31 | > 0.99 |
| Height, cm | 166.20 ± 5.86 | 165.27 ± 7.84 | 0.60 |
| Weight, kg | 62.54 ± 8.70 | 8.70 ± 8.02 | 0.007 |
| BMI | 22.59 ± 2.56 | 20.60 ± 1.98 | 0.001 |
| German nationality | 29 (96.7) | 30 (100) | 0.31 |
| Type of school† | 0.35 | ||
| Realschule | 12 (40.0) | 12 (40.0) | |
| Gymnasium | 16 (53.3) | 18 (60.0) | |
| Other | 2 (6.7) | 0 (0) | |
| Housing | |||
| Living with mother | 0.07 | ||
| Mother | 24 (80.0) | 29 (96.7) | |
| Stepmother | 1 (3.3) | 1 (3.3) | |
| No mother | 5 (16.7) | 0 (0) | |
| Living with father | 0.09 | ||
| Father | 16 (53.3) | 24 (80.0) | |
| Stepfather | 2 (6.7) | 1 (3.3) | |
| No father | 12 (40.0) | 5 (16.7) | |
| Other living situation | 0.23 | ||
| Hospitalized | 1 (3.3) | 0 (0) | |
| Emergency accommodation | 1 (3.3) | 0 (0) | |
| Hostel | 2 (6.7) | 0 (0) | |
| Non-other | 26 (86.7) | 30 (100) | |
| Right-handed | 27 (90.0) | 28 (93.3) | 0.64 |
| Alcohol past 30 d | 21 (70.0) | 18 (60.0) | 0.42 |
| Drugs past 30 d | 10 (33.3) | 2 (6.7) | 0.010 |
| Cigarettes/d | < 0.001 | ||
| None | 9 (30.0) | 27 (90.0) | |
| < 1 | 0 (0) | 2 (6.7) | |
| 2 | 3 (10.0) | 0 (0) | |
| 3 | 5 (16.7) | 0 (0) | |
| 4 | 3 (10.0) | 1 (3.3) | |
| ≥5 | 10 (33.3) | 0 (0) | |
| Acts of NSSI | |||
| Past year | 96.1 ± 77.47 | — | < 0.001 |
| Past 30 d | 2.87 ± 3.64 | — | < 0.001 |
| BPD | 18 (60.0) | — | < 0.001 |
| Primary diagnosis other than NSSI and BPD | < 0.001 | ||
| None | 1 (3.3) | — | |
| Current MDD | 13 (43.3) | — | |
| Past MDD | 10 (33.3) | — | |
| Recurrent MDD | 5 (16.7) | — | |
| Nongeneralized SAD | 1 (3.3) | — | |
| C-GAS score | 52.57 ± 14.49 | 98.33 ± 1.15 | < 0.001 |
BMI = body mass index; BPD = borderline personality disorder; C-GAS = Children’s Global Assessment Scale; MDD = major depressive disorder; NSSI = nonsuicidal self-injury; SAD = social anxiety disorder; SD = standard deviation.
↵* Group differences based on χ2 tests (categorical variables) or t tests (continuous variables).
↵† Realschule = 6 yr and concludes with a general certificate of secondary education; Gymnasium = 8 yr and provides a general university entrance qualification.