Table 1.
Tree analysis with clusters for the 5 endpoints evaluated. For each cluster, the cluster rules and the proportion of observations are given with the mean (SD) for pre- and post-natal mercury exposure (in ppm) and test scores.
| Cluster 1 | Cluster 2 | Cluster 3 | Cluster 4 | Cluster 5 | Cluster 6 | Cluster 7 | Cluster 8 | Cluster 9 | |
|---|---|---|---|---|---|---|---|---|---|
| Cluster rules | KBIT<95.5 | KBIT<95.5 | KBIT<95.5 | KBIT<59.5 | 59.5≤KBIT<95.5 | 59.5≤KBIT<95.5 | KBIT≥95.5 | KBIT≥95.5 | KBIT≥95.5 |
| HOME<22.5 | 22.5≤HOME<29.5 | 22.5≤HOME<29.5 | HOME≥29.5 | 29.5≤HOME<41.5 | HOME≥41.5 | SES<52.75 | SES<52.75 | SES≥52.75 | |
| SES<18.75 | SES≥18.75 | FRS<128.5 | FRS≥128.5 | ||||||
| Proportion | 1.77% | 7.28% | 9.45% | 3.94% | 53.35% | 2.56% | 19.29% | 0.98% | 1.38% |
| Prenatal MeHg | 6.17 (2.88) | 8.49 (4.59) | 5.99 (3.78) | 6.92 (4.03) | 6.58 (4.42) | 7.87 (4.96) | 6.94 (4.29) | 8.79 (7.20) | 7.01 (4.43) |
| Postnatal MeHg | 5.30 (3.56) | 6.22 (3.15) | 6.63 (3.59) | 5.77 (2.93) | 5.96 (3.43) | 4.33 (2.57) | 6.03 (3.61) | 5.19 (4.24) | 3.40 (1.46) |
| WISC III Full IQ | 62.89 (13.55) | 71.86 (8.03) | 78.98 (8.93) | 72.85 (9.82) | 80.83 (9.17) | 91.38 (7.73) | 85.35 (9.46) | 100.4 (12.64) | 107.0 (15.75) |
| Bruninks-Oseretsky | 38.89 (6.19) | 45.43 (6.18) | 45.28 (6.37) | 44.9 (6.11) | 44.13 (5.80) | 45.08 (5.91) | 45.91(5.99) | 45.40 (4.39) | 52.86 (4.22) |
| CTRS hyperacitivity Index | 51.71 (7.16) | 55.23 (11.14) | 57.7 (13.90) | 56.31 (12.89) | 55 (12.59) | 54.54 (14.75) | 53.36 (10.27) | 57.67 (22.94) | 55.67 (19.80) |
| Grooved Dominant hand | 98.11 (15.21) | 97.76 (22.94) | 93.02 (14.35) | 94.85 (19.72) | 92.46 (18.86) | 80.08 (10.19) | 86.74 (15.16) | 79 (11.94) | 73.43 (7.09) |
| Grooved Non-dominant hand | 114.9 (26.67) | 108.5 (22.07) | 105.4 (15.93) | 112.7 (37.38) | 105.4 (27.10) | 87.85 (15.45) | 98.72 (20.80) | 93.8 (16.38) | 87.14 (6.82) |