Guidelines for use of new assessments issued

In the past year, several intellectual assessments have been revised. As a result, the administrative rules for determining a specific learning disability no longer reflect the psychometric properties of the tests.

In response, the Department of Education’s Special Education Programs and the South Dakota Association of School Psychologists developed the following guidelines as best practice when determining eligibility for a specific learning disability.  

Previously, when using a measure of intellectual ability such as the WISC-III, a total score was to be used unless the following occurred. When there was a difference of more than one standard deviation (meaning 16 points) between the verbal score and performance score, the higher of these two scores was used to compare to the student’s achievement score.

Now, the following is recommended. When using a measure of intellectual ability, the total score must be used unless there is an unusually large discrepancy between IQ, Index or Factor scores. To warrant this course of action, each IQ, Index or Factor score must be comprised of at least three subtests and the magnitude of the discrepancy found is to be in the 10 percent or less base rate of the normative sample. If there is such a discrepancy, the higher score must be used.