WAIS Processing Speed Index (PSI) 3

Question 1

Which of the following BEST describes what the Coding subtest measures within the PSI?

Accepted Answer

Psychomotor speed and visual-symbol association learning

Answer

Coding measures how quickly and accurately a person can copy symbols paired with numbers, tapping psychomotor speed and associative learning.

Question 2

When interpreting a low PSI in a child transitioning to adult norms, the clinician should FIRST consider:

Accepted Answer

Whether the subtest scores within the PSI are consistent with each other

Answer

Checking subtest scatter within the PSI determines whether the composite is a valid summary of the domain.

Question 3

A clinician suspects ADHD in an adult. Which PSI pattern would be MOST consistent with inattention rather than motor slowing?

Accepted Answer

Low Symbol Search but average Coding

Answer

Selectively low Symbol Search with preserved Coding suggests attentional scanning difficulties rather than generalized motor slowing.

Question 4

The PSI composite is computed by summing scaled scores and converting to a standard score with mean 100 and SD of:

Accepted Answer

15

Answer

Like all WAIS index scores, the PSI has a mean of 100 and a standard deviation of 15.

Question 5

Traumatic brain injury (TBI) most consistently impairs which WAIS index first and most severely?

Accepted Answer

Processing Speed Index

Answer

TBI reliably and disproportionately reduces processing speed, making PSI the index most sensitive to acquired brain injury.

(WAIS) Wechsler Adult Intelligence Scale Practice Test