Vaurio et al2 examined executive function in children with heavy prenatal alcohol exposure, children with ADHD who were not exposed to prenatal alcohol, and children with neither ADHD nor prenatal alcohol exposure. The children with prenatal alcohol exposure performed worse than the ADHD group on letter fluency and category fluency. On Trail making Test-B, the prenatal alcohol exposure group differed significantly from the control group. The ADHD group did not differ significantly from the control group on this test. The prenatal alcohol exposure and ADHD groups had similar deficits on the WCST and both performed more poorly on letter fluency than category fluency. However, letter fluency was significantly poorer in the prenatal alcohol exposure group. In this study the prenatal alcohol exposure group performed better on the WCST than predicted by IQ but the ADHD group performed more poorly than predicted by IQ. This finding for the prenatal alcohol exposure group was in conflict with previous studies in which executive function deficits remained or worsened when IQ was controlled.2
