Subgroup (2): effect on the significance of change in z score (δzw) from birth to last observed weight within two weeks of death/interview for different potential confounders
| Downward change in z score (δzw) >1 SD | Upward change in z score (δzw) or downward change <1 SD | Residual effect on the significance of the change in z score (δzw) after accounting for each confounder | ||||||
|---|---|---|---|---|---|---|---|---|
| Potential confounders | SIDS (n = 43) | Controls (n = 76) | SIDS (n = 76) | Controls (n = 455) | OR (95% CI)6-150 | p value | ||
| Birth weight <16th centile | 7.0% | 17.1% | 28.9% | 13.0% | 1.90 (1.46–2.48) | <0.0001 | ||
| Gestation <37 weeks | 41.9% | 6.6% | 13.2% | 6.4% | 1.80 (1.38–2.33) | <0.0001 | ||
| Admitted to SCBU | 55.8% | 11.8% | 21.1% | 6.4%6-151 | 1.65 (1.23–2.23) | 0.001 | ||
| Multiple birth | 7.0% | 1.3% | 3.9% | 0.7% | 1.82 (1.39–2.38) | <0.0001 | ||
| Proportion of boys | 55.8% | 40.8% | 63.2% | 51.9% | 1.90 (1.46–2.47) | <0.0001 | ||
| Family with no waged income | 62.8% | 13.2% | 43.4% | 15.4% | 1.81 (1.34–2.43) | <0.0001 | ||
| Young maternal age (<21 years) | 34.9% | 13.2% | 15.8% | 9.0% | 1.81 (1.39–2.36) | <0.0001 | ||
| Mother smoked during pregnancy | 74.4% | 25.0% | 63.2% | 25.5% | 1.80 (1.34–2.43) | <0.0001 | ||
| Any postnatal daily smoke exposure | 53.4% | 21.1% | 46.1% | 21.8% | 1.82 (1.38–2.40) | <0.0001 | ||
| Breastfeeding attempted | 37.2% | 60.5% | 44.7% | 61.1% | 1.82 (1.40–2.37) | <0.0001 | ||
| Infant breastfed >4 weeks | 23.3% | 48.7% | 23.7% | 39.6% | 1.81 (1.39–2.35) | <0.0001 | ||
| Any apparent life threatening event | 14.3%6-152 | 2.6% | 6.7%6-153 | 2.2% | 1.82 (1.41–2.35) | <0.0001 | ||
| Infant with poor health in last week | 11.6% | 5.3% | 7.9% | 3.3% | 1.86 (1.43–2.40) | <0.0001 | ||