TN 2 (06-15)
DI 28010.150 Intelligence Quotient (IQ) Scores in Medical Improvement Review Standard (MIRS) Comparisons
A. Introduction to IQ scores
1. Stabilization of IQ
IQ scores generally tend to stabilize by age 16.
2. New tests usually not needed
Continuing disability reviews (CDR) for adults usually do not require new IQ tests. Often, an IQ test used in the comparison point decision (CPD), especially a test from age 16 or older, will remain relevant and can be used in the CDR process.
3. When to consider
Medical evidence of record sometimes includes new IQ scores. Other cases require new IQ tests because a childhood test score from the CPD is no longer current. Compare prior and current IQ scores in such cases.
B. Use of IQ scores
1. Comparing IQ scores based on the same test
If the CPD and current evidence include IQ scores from the same test (e.g., the WISC-R) find medical improvement (MI) if:
Improvement in IQ scores exceeds one standard error of measurement (SEM), and
The medical or psychological consultant (MC/PC) finds the remaining evidence (including evidence related to adaptive functioning) consistent with such a determination.
2. Comparing IQ scores based on different tests
The SEM cannot be used as above to determine MI if the CPD and current evidence include IQ scores from different tests (e.g., the WISC-R and the WISC-III). The MC/PC must use clinical judgment to determine whether any IQ score change represents MI. They must make a finding of MI only if the remaining evidence (including evidence related to adaptive functioning) is consistent with such a finding.
3. Invalid CPD IQ scores
Consider the error exception in the rare case involving clearly invalid CPD IQ scores; i.e., because of:
Conflict with evidence despite efforts to reconcile the apparent differences, or
Adverse effect on measured IQ by another mental or physical disorder that cannot be controlled.
4. New or improved IQ tests
DI 33535.035 lists IQ tests where the “new or improved” exception may apply. For an explanation of this exception, see DI 28020.250.
DI 24515.055 Evaluation Of Specific Issues Psychological/Psychometric Testing
DI 28010.020 Nature and Quantity of Change Needed to Find Medical Improvement (MI)
DI 28020.350 Prior Error - General