The simple views of reading (SVR) and writing (SVW) provide useful foundations for the interpretation of psychoeducational achievement batteries. Research has established that oral language, decoding, and transcription explain significant variance in reading comprehension and written composition, respectively. However, the specific task demands of subtests influence the relationships among these constructs. As a result, the degree to which the KTEA-3's tasks conform to findings associated with the SVR and SVW are not known. These analyses evaluated the degree to which the KTEA-3 oral language and decoding or transcription tests explained variance in reading comprehension, and written expression. Results inform practitioners as to the relative contributions of each component and useful knowledge when determining which battery to use in psychoeducational evaluation.