Week 6 Tut - WAIS Administration and Interpretation

Question 1

What is the structure of the WAIS-IV?

Answer 1

FSIQ

• Verbal Comprehension Index (VCI): (core = similarities, vocab, info)
• Perceptual Reasoning Index (PRI): (core = block design, matrix reasoning, visual puzzles)
• Working Memory Index (WMI): (core = digit span, arithmetic)
• Processing Speed Index (PSI): (core = symbol search, coding)

Question 2

What is involved in the Verbal Comprehension Index (VCI) with examples?

Answer 2

• Similarities (SI)
  • “I’m going to say two words and ask you how they are alike. In what way
  are TWO and SEVEN alike? How are they the same?”
  overarching theme (they’re both numbers)
  query answers (how are tigers and horses similar “4 legs”)
• Vocabulary (VC)
  • “I am going to say some words. Listen carefully and tell me what each
  word means.”
• Information (IN)
  • Asks general knowledge questions
  scored only 1 or 0 (you know it or not)

Question 3

what does the VCI measure and where does the knowledge come from?

Answer 3

• Ability to process verbal information
• Ability to think with words
• Oral expression and communication of knowledge
• Crystallised (stored) knowledge
• Application of verbal skills to reason and to solve problems
• VCI knowledge comes from school-based learning and verbal interactions with an individual’s family, community, and culture
• Not just what you know, but how well you can put it into words

Question 4

what is the perceptual reasoning index (PRI) with examples?

Answer 4

• Block Design (BD):
  asks clients to make geometric designs from physical blocks
  start from 4 blocks up to 9, more difficult as they go
  timed task
• Matrix Reasoning (MR)
  asks clients to select which of 5 options completes a matrix
• Visual Puzzles (VP)
  asks clients to pick which 3 (of 6) possible puzzle pieces completes a puzzle
  can rotate shapes if needed

Question 5

what does the PRI measure?

Answer 5

• Visual perception
• Nonverbal reasoning
• Ability to interpret and organise visual material within a time limit
• Ability to form abstract concepts and relationships without the use of words
• Visual-motor coordination
• Fluid reasoning

• PRI includes both Visual-Spatial skills (understanding how visual information fits together) and Fluid Reasoning skills (pattern detection and novel problem solving).

Question 6

what is the working memory index (WMI) with examples?

Answer 6

Digit Span (DS)
• Forward: ”Now I’m going to say some numbers. Listen carefully, I can only say them one time. When I am through, I want you to say them back to me in the same order. Just say what I say.” (measure of short-term memory)
• Backward: “Now I am going to say some more numbers, but this time when I stop, I want you to say the numbers backward.” (measure of working memory)
• Sequencing: “Now I am going to say some more numbers. After I say them, I want you to tell me the numbers in order, starting with the lowest number” (measure of working memory)
looks at sustained attention
keep going until 2 wrong in same number length
Your longest Digit Span (LDS) for each subcomponent is an estimate of your short-term or working memory capacity

Arithmetic (AR)
• Asks clients to quickly solve worded arithmetic problems. Focus is on working memory rather than mathematical knowledge (although obviously some of this is required).
timed task starts at end of question (roughly 30 sec)
note if it is repeated

Question 7

what is short-term memory for Digit Span?

Answer 7

ability to temporarily hold information in mind (immediate retention

Question 8

what is working memory for Digit Span?

Answer 8

goes beyond simple retention of information and measures your ability to use and manipulate that information

Question 9

what does PSI measure?

Answer 9

• Visual scanning and discrimination
• Speed of mental operation
• Visuomotor speed and coordination
• Sustained attention
• Visual short-term memory
• Cognitive flexibility and monitoring
• Rate of test-taking

• PSI is your ability to quickly scan, process, and respond to visual information

Question 10

what does WMI measure?

Answer 10

measures:

• short term memory
• ability to sustain attention
• working memory
• auditory processing skills
• mental control
• numerical ability

Question 11

How do you score and standardise the subtest scores of the WAIS-IV?

Answer 11

• The raw scores come from adding up each point the client got correct on each given subtest
• In the manual there are tables for different age groups, so you find the age-range that applies to your client, and convert from a raw score into a scaled score
• Then you sum the scaled scores to get a ‘sum of scaled scores’ for each index

Question 12

Step 1 in standardising the index scores of the WAIS-IV?

Answer 12

you find a the table in the manual and this tells you the composite score (also known as the index score), percentile rank, and 95% confidence interval

Question 13

what does it all mean?++++

Answer 13

• scaled scores
  (M = 10, SD = 3, ‘average’ = 8-11)
• standard scores
  (M = 100, SD = 15, ‘average’ = 90-110)

Question 14

Step 2 interpretation of overall intellectual function of the WAIS-IV?

Answer 14

What is the best way to summarise overall intellectual function?

Is the FSIQ an interpretable measure of global intellectual function?

Look at the 4 WAIS-IV indexes and subtract the highest from the lowest – is the size of the standard score difference less than 1.5SDs (e.g., <23 points)?

If YES, then FSIQ can and should be interpreted

If NO, then FSIQ should not be interpreted as it is not meaningful–check the GAI

• Is the GAI an interpretable measure of global intellectual function?

• Look at the VCI and PRI and subtract and highest from the lowest – is the size of the
standard score difference less than 1.5SDs (e.g., <23 points)?

• If YES, than GAI can and should be interpreted
• If NO, then GAI should not be interpreted as it is not meaningful

Question 15

EXAMPLE: Jack Black’s WAIS-IV Interpretation:

Answer 15

FSIQ
• Biggest (VCI = 102)
• Smallest (PSI = 68)
• 102-68 = 34
• 34 is bigger than 23, so we can’t interpret (i.e., the FSIQ is not meaningful)

GAI
• VIC=102
• PRI=94
• 102-94=8
• 8 is less than 23, so we can interpret the GAI (i.e., it is meaningful)

So, what would we say?

score: 98
range: average
percentile: 45
95% CI: 93-103

“jack obtained a GAI of 98, with a 95% CI between 93-103, and a percentile rank of 45%. This means that we can be 95% certain that Jack’s actual GAI falls somewhere between 93 and 103, placing him in the Average range, with his performance better than 45% of people this age”

Question 16

Step 5 of interpreting index scores of the WAIS-IV?

Answer 16

• Check for inter-subtest scatter – this helps us determine whether the index is measuring a unitary construct, or if subtest-specific factors may be impacting your results
• Subtract the lowest score from the highest score
  (If the different is greater than or equal to 5 points, the index cannot be considered
  unitary and should not be interpreted as a single construct

So for Jack:
• VCI= 12-9=3 
• PRI= 11-6=5 
• WMI= 7-7=0 
• PSI= 5-3=2

Question 17

Step 8 of the WAIS-IV, what would we say about Jack’s index score?

Question 18

Steps 9 and 10 of interpreting the WAIS-IV (personal strengths and weaknesses)?

Answer 18

• Now that we’ve done some normative comparisons (i.e., standardised our clients performances against same-age peers), we want to consider their personal strengths and weaknesses
• We do this by comparing their index and subtests scores against their index/subtest mean
• To determine whether something is a strength or weakness we consider its statistical significance and clinical significance (uncommonness)
• This allows us to identify key assets and high priority concerns
• Statistical Significance considers only whether two scores differ
• Clinical Significance considers the prevalence or frequency of an observed score difference in the general population, also known as a base rate
• A base rate shows the percentage of the population that have that magnitude of difference between two scores

Question 19

how to interpret a base rate in the WAIS-IV?

Answer 19

> = more than
< = less than

> 15% = don’t worry about it

10-15% = interpret on an individual basis

<10% = “CLINICALLY SIGNIFICANT” = Always interpret

Question 20

EXAMPLE: what are jacks strengths weaknesses?

Answer 20

based on scores:

-

Question 21

what is process analysis - WAIS-IV?

Answer 21

• These are additional scores that help you interpret performances on a particular test – Block Design and Digit Span
• For Digit Span, this considers both the scaled score for each subcomponents (Forwards, Backwards, and Sequencing), and comparing their longest spans (raw scores)

Question 22

EXAMPLE: what are Jack’s process scores?

Question 23

what makes a good report for the WAIS-IV?

Answer 23

• Documents all of the relevant information collection
• Gives a clear answer to the referral question/s (which could be “more
  testing/information is needed to be sure, but the answer is likely…”)
• Provides specific, targeted, and actionable recommendations for the client/family/referrer to follow
• Uses plain language to explain psychological concepts (always assume the client will read it) and avoids jargon

Question 24

what are the sections of a WAIS report?

Answer 24

• Reason for Referral
• Presenting Problem
• Background Information (Relevant History)
• Behavioural Observations
• Evaluation Procedures (e.g., what tests did you do)
• Test Results
• Summary and Opinions (also called the ‘Formulation’) - Recommendations