Evidence of validity for the diagnostic achievement battery

This study examined the concurrent validity of the relatively new Diagnostic Achievement Battery (DAB) in relation to the Woodcock-Johnson Psycho-Educational Battery (WJPB). A second issue was the extent to which the DAB could discriminate between learning-disabled and nondisabled students. Correlation coefficients between pairs of similar subtests were in the moderate range (.34 to .71), which indicates that the DAB assesses much the same content as does the WJPB without a high degree of duplication. The DAB was successful in classifying learning-disabled and nondisabled children; the DAB tended to identify more skill deficits than the WJPB or school diagnoses. That such similar tests can produce somewhat different diagnostic outcomes warrants further study. Despite psychometric adequacy, the practical utility of the DAB, as well as that of the WJPB, seems quite limited for decision making and programming and, therefore, may need to be supplemented with curriculum-based assessment.