LD Blog

Even though response-to-intervention (RTI) concepts are being promoted by many, there is still substantial interest in psychometry and Learning Disabilities, as reflected in my recent post about Shelby County’s revision of its LD guidelines (which incorporate both RTI and traditional discrepancy ideas) and in a recent column by Jayne Matthews in the Baltimore Times. In the column, Ms. Matthews refers to explanations of the indices derived from scores on the Weschler Intelligence Scale for Children-IV. Drawing on notes from a lecture by Luann Adams, Ms. Matthews offers these descriptions.

In an IEP [Individual Education Plan] meeting a parent may hear the words WISC-IV (pronounced as “wisk 4”). WISC IV stands for Wechsler Intelligence Scale for Children IV. The WISC-IV is divided into four subtests: 1) Verbal Comprehension Index (VCI) measures verbal abilities that use reasoning, comprehension and conceptualization. For example, it tests for word reasoning by asking a child to identify the common concept being described in a series of clues. 2) Perceptual Reasoning Index (PRI) measures fluid reasoning. For example it tests a child’s ability to identify picture concepts by presenting the child with two or three rows of pictures and then asks the child to choose the picture form each row to form a group with a common characteristic 3) Working Memory Index (WMI) measures attention, comprehension and the ability to hold information in mind temporarily while performing another manipulation with the information. For example it tests for letter–number sequencing by reading a child a sequence of numbers and letters and asking the child to recall the numbers in ascending order and the letters in alphabetical order. 4) Processing Speed Index (PSI) measures the speed of mental and written processing. For example it tests a child’s ability to code asking the child to copy symbols that are paired with simple geometric shapes or numbers. Then using a key, the child draws each symbol in its corresponding shape or box within a specified time limit.

It’s good to demystify these indices, and for doing so I applaud Ms. Matthews and Dr. Adams. Parents should be informed about them. Psychologists should not be able to use them as mumble-jumble that establishes underserved undeserved superior knowledge.

However, I have reservations about making much from the indices. I have yet to see an analysis of a child’s performance on these sorts of measures that actually guides instruction in an IEP. Instructional decisions need to be based on students’ performance on tasks more closely related to academic and social objectives. If students are having trouble with reading (a placeholder), instruction for them should be based on the skills they need to know, not on some assessment that is one-or-more-steps removed from those skills.

A href=”http://www.btimes.com/News/article/article.asp?NewsID=63009&sID=208″>Link to Ms. Matthews column on assessments.