FSIQ and GAI Interpretation Flashcards

When a clinician calculates the GAI instead of the FSIQ, which two index scores are intentionally excluded?

Answer: WMI and PSI

The GAI is derived from the VCI and PRI only, deliberately omitting Working Memory Index and Processing Speed Index scores.

A GAI that is significantly higher than the FSIQ most commonly suggests that the examinee has relative weaknesses in:

Answer: Working memory and processing speed

When GAI > FSIQ by a meaningful amount, it indicates that working memory and/or processing speed are dragging the full-scale score down.

On the WAIS-IV, what is the lowest possible FSIQ score that can be reported?

Answer: 40

The WAIS-IV FSIQ has a floor of 40, meaning scores below 40 are not reliably differentiated by the test.

Which statistical concept explains why a very high or very low FSIQ score is likely to be closer to the population mean upon retesting?

Answer: Regression to the mean

Regression to the mean describes the statistical tendency for extreme scores to move closer to the population average on re-examination.

A clinician interprets an FSIQ of 85 as falling in the 'Low Average' classification. What percentile rank does this score correspond to approximately?

Answer: 16th percentile

An FSIQ of 85 is one standard deviation below the mean of 100 and corresponds to approximately the 16th percentile.

For the GAI to be considered a valid and interpretable composite, the VCI and PRI subtests must first meet what condition?

Answer: The discrepancy between VCI and PRI must not be too large

A large and statistically significant discrepancy between VCI and PRI reduces the meaningfulness of the GAI as a unitary composite.

Which of the following best describes the 'base rate' consideration when interpreting an FSIQ–GAI discrepancy?

Answer: The frequency of that discrepancy in the general population

Base rate refers to how often a given FSIQ–GAI discrepancy size occurs in the normative sample, which helps determine clinical significance.