Table 1.
Beck Depression Inventory scores (median and P25–P75) according adolescents’ characteristics, by sex (Porto, Portugal 2003–2004) (n = 1,988).
| BDI-II | |||||
|---|---|---|---|---|---|
| Girls (n = 1,037) | Boys (n = 951) | ||||
| Median (P25–P75) | p-value ‡ | Median (P25–P75) | p-value ‡ | ||
| Family characteristics | |||||
| Parents’ education, year | |||||
| 0–6 | 6.99 (3.00–12.24) | 0.163 | 3.00 (1.01–6.01) | 0.143 | |
| 7–9 | 5.12 (2.00–10.00) | 3.00 (0.00–6.01) | |||
| 10–12 | 6.01 (2.00–11.00) | 3.08 (1.01–6.01) | |||
| ≥13 | 6.01 (3.00–10.00) | 3.16 (1.01–7.17) | |||
| Household | |||||
| Both parents | 6.01 (2.00–10.00) | 0.004 | 3.00 (1.01–6.01) | 0.618 | |
| Mother/father/other | 6.99 (3.99–11.99) | 3.00 (1.01–7.35) | |||
| Parents’ depression | |||||
| None | 5.00 (2.00–10.00) | 0.001 | 3.00 (1.01–6.01) | 0.054 | |
| At least 1 parent | 6.99 (3.00–11.99) | 3.99 (1.01–8.00) | |||
| Do not know | 6.01 (2.00–9.01) | 2.05 (0.00–6.01) | |||
| Individual characteristics | |||||
| Age at menarche, year | |||||
| ≤10 | 6.99 (3.00–15.75) | 0.010 | |||
| 11 | 6.99 (3.00–11.99) | ||||
| 12 | 6.01 (2.00–11.55) | ||||
| ≥13 | 5.00 (2.00–9.01) | ||||
| Pre-menarche | 5.00 (2.00–8.04) | ||||
| BMI † | |||||
| <p85 | 6.01 (2.00–11.00) | 0.228 | 3.00 (1.01–6.01) | 0.813 | |
| ≥p85 & <p95 | 6.99 (3.00–10.00) | 3.50 (1.01–6.99) | |||
| ≥p95 | 6.01 (3.00–13.00) | 3.00 (1.01–6.99) | |||
| Behaviours | |||||
| Sleeping duration, h | |||||
| 8.5–9.5 | 5.63 (2.00–10.00) | 0.012 | 3.00 (1.01–6.01) | 0.956 | |
| ≤8.5 | 6.99 (3.00–11.99) | 3.00 (1.01–6.01) | |||
| ≥9.5 | 6.01 (3.00–11.00) | 3.00 (1.01–6.01) | |||
| Smoking | |||||
| Never | 5.00 (2.00–9.45) | <0.001 | 3.00 (1.01–6.01) | 0.072 | |
| Ever | 8.40 (3.99–15.75) | 3.00 (1.01–8.00) | |||
| Drinking alcohol | |||||
| Never | 6.01 (2.00–10.00) | 0.002 | 3.00 (1.01–6.01) | 0.038 | |
| Ever | 6.30 (3.00–11.99) | 3.99 (1.01–6.99) | |||
| Physical exercise | |||||
| Never | 6.30 (3.00–11.99) | 0.152 | 3.00 (1.01–6.99) | 0.127 | |
| ≤1 time/week | 5.00 (3.00–9.01) | 3.00 (1.01–6.01) | |||
| 2–3 times/week | 6.01 (2.00–10.00) | 3.00 (1.01–6.01) | |||
| ≥4 times/week | 4.49 (2.00–6.99) | 3.99 (1.01–8.00) | |||
Abbreviations: BDI-II, Beck Depression Inventory, Second Edition; BMI, body mass index (calculated as weight in kilograms divided by height in meters squared). † BMI was classified according to the age- and sex-specific BMI percentiles, elaborated by the United States Centers for Disease Control and Prevention. ‡ Mann Withney or Kruskal-Wallis tests.