The Use of the Peabody Individual Achievement Test and the Woodcock Reading Mastery Tests in the Diagnosis of a Learning Disability in Reading: A Caveat

Using a counterbalanced order, 34 learning disabled students from three schools in southern Appalachia were given the Peabody Individual Achievement Test (PIAT) and the Woodcock Reading Mastery Tests (Woodcock). PIAT Reading Recognition and Woodcock Word Identification scores were compared, as were the PIAT Reading Comprehension and Woodcock Passage Comprehension scores. The results from a correlated t test revealed highly positive and significant correlations but equally highly significant differences between the means (p < .001). The PIAT scores were uniformly higher. The results were interpreted as supporting the results of previous research studies. Further analysis revealed that, according to the regulations of the state of Tennessee, fewer students were certifiable as learning disabled in reading by the scores from the PIAT than by scores from the Woodcock. Cautions are expressed about the use of the PIAT (designed by its authors to be a screening device) in the diagnosis of a learning disability in reading unless or until further research demonstrates the concurrent validity of the PIAT.