Univariate association between gestational age (cases = 834; controls = 20 100) and birth weight at term (cases = 763; controls = 17 625) and the risk of hyperkinetic disorder
| Controls n = 20 100 | Cases n = 834 | ||
|---|---|---|---|
| Results presented as rate ratios (RR) with 95% confidence intervals (CI) from a conditional logistic regression model. | |||
| *p<0.05. | |||
| †Cases and controls are matched for age, sex, and date of birth. | |||
| Gestational age (wk) | |||
| <34 | 298 | 34 | 3.1 (2.2–4.5) |
| 34–36 | 544 | 37 | 1.8 (1.3–2.6) |
| 37–39 | 6629 | 298 | 1.2 (1.0–1.4)* |
| 40–42 | 12365 | 456 | 1 |
| 43–44 | 264 | 9 | 0.9 (1.0–1.4) |
| Children born at 37–41 completed weeks of gestation | Controls n = 17 625 | Cases n = 763 | |
| Birth weight at term (g) | |||
| <1500 | 1 | 0 | – |
| 1500–2499 | 288 | 27 | 2.4 (1.6–3.6) |
| 2500–2999 | 1888 | 127 | 1.7 (1.4–2.0) |
| 3000–3999 | 12099 | 478 | 1 |
| 4000–5990 | 3349 | 131 | 1.0 (0.8–1.2) |