What are supplemental scores? Why are they in quartiles?
Supplemental scores are additional pieces of information (apart from the standard scores) that can help in determining areas of strength or weakness. Quartiles provide general normative information; these scores are not intended to be used when determining eligibility. However, the use of quartiles for Reading Speed and Reading Comprehension can be very useful when used with the Reading Rate chart found near the end of the record form. The interpretation of the Reading Rate chart can be found in the Examiner's Manual.
The quartile scores can provide useful information to IEP teams as they consider the types of accommodations that may be necessary for students. For example, one common question is whether or not students are in need of additional time for state standardized testing. By evaluating the contrast between a student's performance on reading speed and accuracy, more appropriate decisions can be made regarding additional time for testing.