IQ scores generally stabilize after age 16. For additional information, see DI 24583.055I.7.

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.

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 Other cases require new IQ tests because a childhood test score from the CPD is no longer current.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.

IQ scores stabilize after age 16 and may be considered current indefinitely unless there is inconsistency with current functioning or an intervening injury or insult has since occurred that would affect the IQ score. If the individual is retested after age 16 and administered the same test, the score should not demonstrate much variance.

When the CPD and current evidence include IQ scores from the same test (e.g., the WISC-IV) medical improvement (MI) may occur in the individual's intellectual disorder (or related cognitive disorder) only if:

1. a. 

   Improvement in IQ scores exceeds one standard error of measurement (SEM) and cannot be reasonably accounted for by the practice effect (DI 24583.055F.2.) or another confounding variable, and

2. b. 

   The medical or psychological consultant (MC/PC) finds the remaining evidence (including evidence related to adaptive functioning) consistent with a decrease in medical severity.

Changes in IQ scores exceeding the SEM cannot be used as above to determine MI if the CPD and current evidence include IQ scores from different tests or different versions of the same test series (e.g., the WISC-III and the WISC-V). The MC/PC must use clinical judgment to determine whether any IQ score change represents MI. Find MI only if the remaining evidence (including evidence related to adaptive functioning) is consistent with such a finding.

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.