Wechsler Test Adult Intelligence Scale (WAIS-IV) Clinical Applications 2 — Questions and Answers
Question 1: A clinician notes a 20-point discrepancy between a patient's Verbal Comprehension Index and Perceptual Reasoning Index. What is the most appropriate clinical interpretation?
- The Full Scale IQ alone fully summarizes ability
- The FSIQ may be less interpretable and index-level analysis is warranted (Correct answer)
- The test should be readministered immediately
- The patient is malingering
Correct answer: The FSIQ may be less interpretable and index-level analysis is warranted
A large index discrepancy suggests the FSIQ masks meaningful ability differences, so interpretation should shift to the index scores.
Question 2: Which WAIS-IV index is considered most sensitive to the effects of anxiety, distractibility, and attentional problems during testing?
- Verbal Comprehension Index
- Perceptual Reasoning Index
- Working Memory Index (Correct answer)
- General Ability Index
Correct answer: Working Memory Index
The Working Memory Index taxes sustained attention and concentration, making it vulnerable to anxiety and distractibility.
Question 3: The General Ability Index (GAI) is often used clinically because it:
- Includes only Processing Speed subtests
- Minimizes the influence of Working Memory and Processing Speed (Correct answer)
- Replaces the need for any index scores
- Is derived solely from Digit Span
Correct answer: Minimizes the influence of Working Memory and Processing Speed
The GAI combines Verbal Comprehension and Perceptual Reasoning subtests, reducing the impact of Working Memory and Processing Speed.
Question 4: A patient with a traumatic brain injury shows intact VCI and PRI but markedly low Processing Speed Index. This pattern most likely reflects:
- Preserved reasoning with reduced cognitive efficiency (Correct answer)
- Global intellectual disability
- Deliberate underperformance
- Superior overall functioning
Correct answer: Preserved reasoning with reduced cognitive efficiency
Reasoning abilities can remain intact while processing speed drops, a common finding after brain injury.
Question 5: When a clinician suspects a subtest score was affected by a broken pencil or examiner error, the best practice is to:
- Report the score without comment
- Document the circumstance and interpret that subtest cautiously (Correct answer)
- Double the raw score
- Discard the entire protocol
Correct answer: Document the circumstance and interpret that subtest cautiously
Testing irregularities should be documented and the affected score interpreted with appropriate caution.
Question 6: The Cognitive Proficiency Index (CPI) combines which two indexes?
- VCI and PRI
- Working Memory and Processing Speed (Correct answer)
- VCI and WMI
- PRI and PSI
Correct answer: Working Memory and Processing Speed
The CPI is formed from Working Memory and Processing Speed, reflecting cognitive efficiency.
Question 7: Base rate data in WAIS-IV interpretation is most useful for:
- Converting raw scores to scaled scores
- Determining how unusual a score discrepancy is in the population (Correct answer)
- Timing the subtests
- Selecting which subtests to administer
Correct answer: Determining how unusual a score discrepancy is in the population
Base rates indicate how frequently a given discrepancy occurs, helping judge its clinical rarity.
Wechsler Test Adult Intelligence Scale (WAIS-IV) Clinical Applications 2
A clinician notes a 20-point discrepancy between a patient's Verbal Comprehension Index and Perceptual Reasoning Index.
What is the most appropriate clinical interpretation?