WAIS Score Comparisons and Discrepancy Analysis 2

Question 1

The General Ability Index (GAI) is composed of which two WAIS-IV index scores?

Accepted Answer

Verbal Comprehension Index (VCI) and Perceptual Reasoning Index (PRI)

Answer

The GAI is derived from the VCI and PRI subtests, providing an estimate of general intellectual ability that is less influenced by working memory and processing speed.

Question 2

Why is the GAI preferred over the FSIQ when an examinee has a significant discrepancy between GAI and the Cognitive Proficiency Index (CPI)?

Accepted Answer

A large GAI–CPI discrepancy indicates that the FSIQ is not a valid unitary estimate of general intelligence

Answer

When GAI and CPI differ substantially, the FSIQ blends two dissimilar cognitive profiles into one number, making it a misleading summary; the GAI better represents reasoning and knowledge in those cases.

Question 3

The Cognitive Proficiency Index (CPI) on the WAIS-IV is derived from which two index scores?

Accepted Answer

Working Memory Index (WMI) and Processing Speed Index (PSI)

Answer

The CPI combines WMI and PSI to measure cognitive efficiency—how quickly and accurately an individual manipulates and processes information.

Question 4

Regression to the mean is an important consideration in WAIS-IV discrepancy analysis because:

Accepted Answer

Predicted achievement scores derived from ability scores must account for the fact that extreme ability scores overestimate expected achievement

Answer

Because of imperfect test-criterion correlations, predicting achievement from an extreme ability score (very high or very low) requires adjusting toward the mean to avoid over- or under-predicting performance.

Question 5

When comparing WAIS-IV index scores in older adults (ages 65–90), clinicians must be especially cautious because:

Accepted Answer

Normal age-related declines in PSI and WMI can make discrepancies appear clinically significant when they reflect typical aging

Answer

Processing speed and working memory decline with normal aging, so a PSI or WMI that is lower than VCI may reflect typical developmental change rather than pathology in older adults.

(WAIS) Wechsler Adult Intelligence Scale Practice Test

(WAIS) Wechsler Adult Intelligence Scale Practice Test

WAIS Score Comparisons and Discrepancy Analysis 2