| Characteristic | Mean difference (95% CI) in blood lead level (natural log units) | |||
|---|---|---|---|---|
| Unadjusted | P | Adjusted* | P | |
| Child‐related factors | ||||
| Age (per year) | 0.00 (–0.12 to 0.13) | 0.96 | 0.03 (–0.11 to 0.16) | 0.71 |
| Sex (boys v girls) | 0.05 (–0.03 to 0.13) | 0.22 | 0.06 (–0.02 to 0.15) | 0.15 |
| Weight (per kg) (N = 494) | –0.003 (–0.011 to 0.006) | 0.51 | –0.003 (–0.011 to 0.006) | 0.53 |
| Socio‐demographic factors | ||||
| Mean household income (per $10 000)† (N = 520) | –0.031 (–0.051 to –0.012) | 0.002 | –0.035 (–0.056 to –0.013) | 0.002 |
| Maternal education (N = 521) | ||||
| Bachelor degree or higher | Reference | Reference | ||
| Year 12 or equivalent, diploma, apprenticeship or trade certificate | 0.11 (0.03 to 0.19) | 0.010 | 0.03 (–0.07 to 0.13) | 0.54 |
| Did not complete secondary education | 0.09 (–0.09 to 0.26) | 0.33 | 0.04 (–0.15 to 0.23) | 0.68 |
| Index of Relative Socio‐economic Disadvantage (N = 522) | ||||
| Highest tertile (least disadvantaged) | Reference | Reference | ||
| Middle tertile | 0.14 (0.04 to 0.23) | 0.003 | 0.08 (–0.03 to 0.18) | 0.14 |
| Lowest tertile (most disadvantaged) | 0.08 (–0.01 to 0.19) | 0.08 | –0.04 (–0.15 to 0.07) | 0.48 |
| Residential factors | ||||
| Age of family home ≥ 50 years (N = 434) | 0.18 (0.08 to 0.27) | < 0.001 | 0.13 (0.02 to 0.24) | 0.020 |
| Distance of home from Point Henry (N = 515) | ||||
| > 10 km | Reference | Reference | ||
| 5–10 km | 0.15 (0.07 to 0.23) | < 0.001 | 0.11 (0.01 to 0.21) | 0.031 |
| < 5 km | 0.18 (–0.15 to 0.52) | 0.28 | 0.19 (–0.17 to 0.56) | 0.30 |
*
Adjusted for mean household income (except “mean household income”), age of family home (except: “Age of family home ≥ 50 years”), distance of family home from Point Henry (except “distance of family home from Point Henry”).
†
Mean of household income during pregnancy and first year after child's birth, censored at $100 000.