Our results support and extend the prior literature demonstrating numerous shared deficits for both FASD and ADHD compared to controls (set shifting, complex motor skills, social skills, static balance, communication skills, parent reports of behavior), which hinders diagnostic specificity (Mattson, Crocker, et al., 2011; Mattson & Riley, 2011). However, in spite of these similarities, the presence of an ADHD diagnosis did not have the same impact on neuropsychological functioning in the exposed sample as it did in the non-exposed sample emphasizing that these two clinical conditions are not identical. We found that certain measures may be more sensitive in differentiating between ADHD and FASD. These results add to previous reports demonstrating differences between FASD and ADHD on attention (Coles, et al., 1997; Kooistra, Crawford, Gibbard, Kaplan, & Fan, 2011), response inhibition (Burden, et al., 2010), motor response time and balance (Kooistra, et al., 2010), overall deficits in letter fluency (Vaurio, et al., 2008), verbal learning and memory (Crocker, et al., 2011), and mathematics (Jacobson, Dodge, Burden, Klorman, & Jacobson, 2011). Further, this study indicates that measures of verbal comprehension and perceptual reasoning are also sensitive assessment measures for distinguishing alcohol-exposed children from non-exposed children with ADHD.
