Table 1.
Frequency characteristics of the study population
| Variable | N (%) | M/SD or Median/Range |
|---|---|---|
| Independent Variables | ||
| BDNF Val66Met | 1106 | |
| Val/Val | 722 (65 %) | |
| Val/Met | 345 (31 %) | |
| Met/Met | 39 (4 %) | |
| 5-HTTLPR | 1015 | |
| l/l | 318 (31 %) | |
| l/s | 473 (47 %) | |
| s/s | 224 (22 %) | |
| Apgar 5 min (Median/Range) | 1079 | 10/0–10 |
| Low <7 | 12 (1 %) | |
| Birthweight (Mean/SD) | 1081 | 3554.01/540.80 |
| Low <2500 g | 33 (3 %) | |
| Very low <1500 g | 1 (0 %) | |
| Gestational length (Median/Range) | 1086 | 40/31–43 |
| Preterm <37 weeks | 50 (5 %) | |
| Very preterm <32 weeks | 2 (0 %) | |
| Small for gestational age | 1051 | |
| Yes | 21 (2 %) | |
| Smoking during pregnancy | 1106 | |
| Yes | 172 (16 %) | |
| Neonatal illness | 1106 | |
| Yes | 97 (9 %) | |
| Non-optimal pregnancy/birth | 1106 | |
| Yes | 287 (26 %) | |
| EPDS (Median/Range) | 1097 | 4/0–21 |
| ≥ 10 | 121 (11 %) | |
| Life events (Median/Range) | 980 | 4/0–18 |
| ≥ 90th percentile | 62 (6 %) | |
| LSS (Median/Range) | 1106 | 4/0–19 |
| ≥ 90th percentile | 79 (7 %) | |
| Parental unemployment | 930 | |
| One or both parents unemployed | 109 (12 %) | |
| Sex | 1106 | |
| Boys | 562 (51 %) | |
| Parental immigration status | 1106 | |
| Children of immigrants | 127 (11 %) | |
| Dependent Variables | ||
| CBCL Internalizing | 983 | |
| ≥ 90th percentile | 83 (8 %) | |
| CBCL Anxious Depressed | 983 | |
| ≥ 90th percentile | 52 (5 %) | |
| CBCL Withdrawn | 983 | |
| ≥ 90th percentile | 57 (6 %) | |
| CBCL Externalizing | 983 | |
| ≥ 90th percentile | 85 (9 %) | |
| CBCL Aggressive | 983 | |
| ≥ 90th percentile | 75 (8 %) | |
| CBCL Destructive | 983 | |
| ≥ 90th percentile | 84 (9 %) |
BDNF brain derived neurotrophic factor, 5-HTTLPR serotonin transporter gene-linked polymorphic region, EPDS Edinburgh postnatal depression scale, LSS life stress score, CBCL child behaviour checklist