“…428 Unfortunately, the underlying premise on which the strategy is based, that of differentiated, discriminable subtypes of learning disabilities, may not accurately describe the domain. Although it is possible that small specific clusters of learning disabilities, such as visual-motor deficits and verbal deficits, may exist (McCue, Goldstein, Shelly, & Katz, 1986), these clusters taken together may account for only a small proportion of the total domain. Thus several investigators now take the position that learning disabilities are intrinsically undifferentiated disorders (McCue et al, 1986;McClearn, (977) or, in the words of one group of investigators, 'The potential number of subtypes of ... learning disabilities is limited only by the ability of the neuropsychological tests to differentiate efficiently the components and subcomponents involved in any particular neuropsychological or cognitive task" (Hynd, Obrzut, Hayes, & Becker, 1986, p. 469).…”