Table 3. Mean IQ and 2009 school performance by blood concentrations of lead in preschool children.
Blood concentrations of lead (µg/dL) | ANOVA | Post-hoc analysis, LSD (p) | ||||||
<8 (A) | 8- <10(B) | ≥10 (C) | F | p | A vs. B | A vs. C | B vs. C | |
IQ | N = 1016 | N = 182 | N = 103 | |||||
PIQ | 104.46(14.93) | 103.32(15.58) | 100.75(16.03) | 3.04 | .048 | .349 | .018 | .168 |
VIQ | 104.23(14.80) | 103.65(15.03) | 103.08(14.65) | 0.36 | .696 | .627 | .453 | .755 |
FIQ | 104.55(14.36) | 103.66(14.22) | 101.86(15.25) | 1.78 | .169 | .442 | .072 | .313 |
School performance | N = 421 | N = 79 | N = 49 | |||||
Chinese | 89.33(9.20) | 83.44(13.97) | 82.12(16.67) | 17.30 | .000 | .000 | <.001 | .503 |
Math | 90.32(9.20) | 84.29(14.66) | 83.04(19.42) | 16.32 | .000 | .000 | <.001 | .545 |
English | 91.29(10.41) | 84.16(18.10) | 83.37(19.71) | 16.59 | .000 | .000 | <.001 | .732 |