Factors Associated with Arithmetic-and-Reading Disability and Specific Arithmetic Disability

Factors associated with arithmetic-and-reading disability and specific arithmetic dis-ability were investigated in a large sample of representative New Zealand children. Evidence was sought for Rourke's hypothesis (Rourke & Finlayson, 1978; Rourke & Strang, 1978,1983) that these two types of arithmetic disability show reverse patterns of strengths and weaknesses with regard to verbal and nonverbal skills. This "crossover" effect was clearly evident for boys but noticeably absent for girls. When compared to a nondisabled control group, arithmetic-and-reading disabled boys showed deficits primarily, but not exclusively, on verbal tasks. Girls with arithmetic-and-reading dis-ability were best characterized as showing a general (verbal and nonverbal) deficit. In specific arithmetic disabled boys there was evidence of predominantly nonverbal but also verbal deficits while girls with specific arithmetic disability did not differ from the control group on any of the measures included in this study. A number of studies have reported data suggesting that poor achievement in arithmetic may be largely attributable to the same lan-guage-based deficits that underlie poor reading achievement (e.g.,