Diagnostic Test Pattern Differences among LD, ED, EMH, and Multi-Handicapped Students

Abstract
This study examined diagnostic test data in conjunction with familial and cultural information taken from the case files of children who had been diagnosed as LD, EMH, or ED, multi-handicapped or other, to determine their discriminative efficacy in differentiating LD children from non-LD children. A total of 1324 children between the ages of 6 and 17 years with about average intelligence, as measured by performance on the WISC-R (X FSIQ = 87.30, SD = 15.68), were used in this study. Six discriminant functions analyses were performed on variables selected from the above three sources of information. The results of these discriminant analyses consistently failed to discriminate LD children from the other groups. A transpose factor analysis performed on these variables showed considerable overlap of variables between factors. A review of research examining the discriminative efficacy of widely used diagnostic tests indicates that these tests have little utility in distinguishing LD from non-LD children. A more appropriate diagnostic model is proposed which accounts for the child’s unique processing (organizing, storing, rehearsing, and retrieving) of information relative to his content base and ability to perform a corresponding behavior.