Table 2.
Motor skills in children at age 7 years by category of prenatal lead, cadmium or mercury exposure: complete cases (n = 1558).
| Prenatal blood lead (μg/dl) |
Prenatal blood cadmium (μg/l) |
Prenatal blood mercury (μg/l) |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| <5.00 |
≥5.00 |
p | <0.25 |
≥0.25 |
p | <2.00 |
≥2.00 |
p | ||
| n = 1337 | n = 221 | n = 756 | n = 802 | n = 770 | n = 788 | |||||
| Balance | Heel to toe steps | |||||||||
| 15 (good) | 677 (85.4%) | 116 (14.6%) | 0.610 | 402 (50.7%) | 391 (49.3%) | 0.081 | 379 (47.8%) | 414 (52.2%) | 0.190 | |
| < 15 | 660 (86.3%) | 105 (13.7%) | 354 (46.3%) | 411 (53.7%) | 389 (51.3%) | 370 (48.7%) | ||||
| Ball skills | Beanbag (n) | |||||||||
| 4–10 (good) | 1157 (861%) | 187 (13.9%) | 0.442 | 650 (48.4%) | 694 (51.6%) | 0.751 | 659 (49.0%) | 685 (51.0%) | 0.441 | |
| 0–3 | 180 (84.1%) | 34 (15.9%) | 106 (49.5%) | 108 (50.5%) | 111 (51.9%) | 103 (48.4%) | ||||
| Manual dexterity | Threading lace (s) | |||||||||
| 9–22 (good) | 722 (86.2%) | 116 (13.8%) | 0.676 | 393 (47.1%) | 445 (52.9%) | 0.166 | 401 (47.9%) | 437 (52.1%) | 0.181 | |
| 23–105 | 615 (85.4%) | 105 (14.4%) | 363 (50.4%) | 357 (49.6%) | 369 (51.2%) | 351 (48.8%) | ||||
| Peg board (s) | ||||||||||
| Preferred hand | ||||||||||
| 15–22 (good) | 7814 (86.5%) | 122 (13.5%) | 0.370 | 437 (48.4%) | 466 (51.6%) | 0.904 | 440 (48.7%) | 463 (51.3%) | 0.519 | |
| 23–46 | 556 (84.9%) | 99 (15.1%) | 319 (48.7%) | 336 (51.3%) | 330 (50.4%) | 325 (49.6%) | ||||
| Non-preferred hand | ||||||||||
| 15–25 (good) | 746 (86.1%) | 120 (13.9%) | 0.678 | 415 (47.9%) | 451 (52.1%) | 0.595 | 407 (47.2%) | 451 (52.8%) | 0.053 | |
| 26–63 | 591 (85.4%) | 101 (14.6%) | 341 (49.3%) | 351 (50.7%) | 361 (52.5%) | 331 (47.8%) | ||||
Manual dexterity variables categorised on median value.
Participants with poor attention to tasks excluded.