This page contains the reference tables used to determine student eligibility under the Specific Learning Disability category. These tables are used by district evaluators and others who perform diagnostic evaluations as part of the identification process for special education. If you have questions regarding the reference tables on this page, please call Ms. Toyah Robey at (502) 564-4970.
How to use the Discrepancy Tables
The following links include the pairs of aptitude and achievement tests that might be used in calculating an aptitude-achievement discrepancy using the Regression Estimated True Score Method.
For each test pairing, the age level and table reference is provided. For example, the line looks like the information below:
Apt Test Achievement Test Pairing Age Table/Col
WISC-IV FS WJ-III Basic Math 6 2-B
In this pairing the WISV-IV Full Scale IQ score and WJ-III Basic Math score would be used. For a student age 6, the appropriate table of criterion values would be Table 2. In Table 2 the user would locate the criterion value in Column B that corresponds to the student’s WISV-IV Full Scale IQ score. This criterion value would then be compared to the student’s achievement score on the WJ-III Basic Math score test.
Special Notes
The L.D. Advisory Group recommends a minimum 14 point difference between the Verbal and Non-Verbal IQs on the Stanford-Binet 5 before considering the higher of the two scores as the best measure to be used in determining an aptitude/achievement discrepancy.
The WISC-IV does not have a Verbal and Performance Scale. It has four index scores made up of either 2 or 3 subtests. The manual states that all four indexes must be given to obtain a full scale score. Due to the lack of breath of each of the indexes they are not intended to represent overall cognitive functioning, so they are not tabled individually.