Multiple logistic regression derived, mutually adjusted odds ratio (OR) and 95% confidence interval (CI) for upper limb injury by study variables
| Variable | Category or increment | OR | 95% CI | p Value |
|---|---|---|---|---|
| Paternal age (years) | <35 | 2.73 | 1.07 to 7.02 | 0.04 |
| 35–49 | Baseline | 0.32 to 1.67 | 0.45 | |
| ≥50 | 0.73 | |||
| Paternal education (years) | 0–12 | Baseline | ||
| >12 | 0.60 | 0.33 to 1.09 | 0.09 | |
| Persons per room | ∼0.33 | 0.49 | 0.35 to 0.70 | 0.001 |
| Hyperactivity | Low quartile | 0.80 | 0.44 to 1.47 | 0.48 |
| Intermediate quartiles (2nd and 3rd) | Baseline | 0.18 to 0.69 | 0.0062 | |
| Upper quartile | 0.35 | |||
| Previous upper limb injury | Yes (v no) | 3.89 | 2.13 to 7.11 | 0.001 |
| Handedness | Right handed | Baseline | ||
| Left handed | 1.90 | 0.79 to 4.57 | 0.15 | |
| Ambidextrous | 0.99 | 0.31 to 3.16 | 0.98 |