Profile analysis Evaluate for differences between the four Indexes Determine whether the subtest scaled scores differ significantly from each other

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2 Profile analysis Evaluate for differences between the four Indexes Determine whether the subtest scaled scores differ significantly from each other Obtain the base rates for differences between the Indexes Obtain the base rates for differences between some of the subtest scaled scores Determine base rates for inter subtest scatter Develop hypotheses and make interpretations. 2

3 Full Scale Verbal Comprehension Perceptual Reasoning, Working Memory Processing Speed 3

4 Global estimate of a adult's current level of cognitive ability Usually the most reliable and valid estimate of the adult's intellectual ability. Provides information about the adult's relative standing in the general (standardization) population Usually used to obtain a descriptive classification of the adult's IQ level Very Superior Superior High Average Average Low Average Borderline Extremely Low; see Converting the Full Scale IQ to a percentile rank often helpful in explaining it to individuals unfamiliar with standard scores Use the Full Scale IQ as the primary index of a adult's intellectual ability unless there is a compelling reason to use one of the Indexes 4

5 Measures verbal comprehension application of verbal skills and information to the solution of new problems ability to process verbal information ability to think with words crystallized knowledge cognitive flexibility (including the ability to shift mental operations) ability to self monitor. Oral input (questions) Oral output (answers) Nonverbal factors such as forming a mental picture of the words or questions also may playa role in solving Verbal Comprehension tasks. 5

6 Measures Perceptual reasoning, ability to think in terms of visual images and manipulate them with fluency cognitive flexibility (including the ability to shift mental operations) relative cognitive speed, ability to interpret or organize visually perceived material within a time limit nonverbal ability ability to form abstract concepts and relationships without the use of words fluid reasoning, ability to self monitor. The four subtests Verbal factors also may play a role in solving Perceptual Reasoning tasks. using verbal descriptions in thinking about blocks and block placement categorizing the pictures into logical groups on Picture Concepts Using verbal processing to solve Matrix Reasoning problems verbally identifying parts of objects on Picture Completion 6

7 Measures working memory short term memory the ability to sustain attention, Numerical ability encoding ability, auditory processing skills Cognitive flexibility (including the ability to shift mental operations), Ability to self monitor. Verbal and nonverbal factors play a role in solving Working Memory tasks. 7

8 Measures Processing speed rate of test taking perceptual discrimination speed of mental operation, psychomotor speed attention Concentration short term visual memory visual motor coordination, numerical ability, cognitive flexibility (including the ability to shift mental operations) ability to self monitor. 8

9 Looks at a adult's unique ability pattern, going beyond the information contained in the Full Scale IQ or Indexes Knowledge of ability patterns can help in formulating teaching strategies and other types of interventions. The Full Scale IQ is a valuable measure of general intellectual l ability Tells us little about the specific underlying abilities on which it is based. Examining the subtest scale scores can show strengths or weaknesses. 9

10 Example Profiles 1. A flat profile with all subtest scaled scores far above average (e.g., from 14 to 16) suggests that a adult is intellectually gifted and may profit from instruction that capitalizes on the adult's exceptional intellectual skills. 2. A flat profile with all subtest scaled scores far below average (e.g., from 2 to 4) suggests that a adult has limited intellectual ability and needs specialized instruction appropriate for the adult's low level of functioning. 3. A variable profile, with subtest scaled scores varying over a large range of scaled scores (e.g., from 3 to 16), suggests that a adult has unique strengths and weaknesses and may benefit from specialized instruction designed to capitalize on the strengths and remediate the weaknesses. 4. A profile of subtest scaled scores within normal limits (e.g., from 8 to 12) suggests average ability across all areas measured and suggests that a adult needs a standard program of instruction. The goal of profile analysis is to generate hypotheses about a adult's abilities, which then need to be checked against other information about the adult (e.g., parent and teacherreports, records of academic performance). 10

11 The simplest approach to subtest profile analysis Evaluate subtest scores in reference to the norm group A mean of 10 with a standard deviation of 3 serves as the reference point for the norm group. You can describe subtest scaled scores using a categorical approach Subtest scaled scores of 13 to 19 always indicate a strength (one to three standard deviations above the mean). Subtest scaled scores of 8 to 12 always indicate average ability (within one standard deviation of the mean). Subtest scaled scores of I to 7 always indicate a weakness (one to three standard deviations below the mean). 11

12 In applying a significant difference approach, you will need to answer questions like the following: Do the Indexes of interest differ significantly from each other (e.g., Verbal Comprehension vs. Perceptual Reasoning)? Do the subtest scaled scores of interest differ significantly from each other (e.g., Vocabulary vs. Block Design)? Do the subtest scaled scores of interest differ significantly from the mean of their respective Composites (e.g., Similarities vs. the Verbal Comprehension mean)? Do the subtest scaled scores of interest differ significantly from the mean of the other subtests administered (e.g., Similarities vs. the mean of the other nine subtests administered)? Whatever comparisons you choose to make you must determine whether the differences are statistically significant (i.e., too large to be likely to have occurred by chance). 12

13 A second approach to profile analysis is to determine the frequency with which the differences between scores in a adult s prolile occurred in the standardization sample; this is called the Base rate Approach or the Probability of Occurrence Approach. 13

14 1. Compare the VCI, PRI, WMI, and PSI with each other. 2. Compare the subtest scaled scores within each Composite with the adult's mean scaled score for that Composite and for the Full Scale. 1. This is where we stop for the WAIS assignment. 3. Compare sets of individual subtest scaled scores (i.e., planned paired comparisons). 4. Compare the range of subtest scaled scores with the base rate found in the standardization sample. 5. Compare sets of individual id Process scaled ld scores. 6. Compare Process scaled score differences with the base rates found in the standardization sample. 14

15 Verbal comprehension skills are better developed than perceptual reasoning skills. Verbal processing is better developed than visual spatial processing. Auditory vocal processing is better developed d than visual discrimination processing. Knowledge acquired through accumulated experience is btt better developed d than knowledge needed dd to solve nonverbal problems. Retrieval of verbal information from long term memory is better developed than nonverbal problem solving. Crystallized knowledge is better developed than fluid reasoning. 15

16 Perceptual reasoning skills are better developed than verbal comprehension skills. Visual spatial processing is better developed than verbal processing. Visual discrimination i i processing is better developed d than auditory vocal processing. Knowledge needed to solve nonverbal problems is better developed d than knowledge acquired through h accumulated ltd experience. Nonverbal problem solving is better developed than retrieval of verbal information from long term memory. Fluid reasoning is better developed than crystallized knowledge. 16

17 Verbal comprehension is. better developed than working memory. Verbal processing is better developed than short term auditory memory. Auditory vocal processing is better developed d than use of encoding strategies. Long term verbal memory is better developed than short term auditory memory. Retrieval of verbal information from long term memory is better developed than retrieval of information from short term memory. Crystallized knowledge is better developed than short term auditory memory. 17

18 Working memory is better developed than verbal comprehension. Short term auditory memory is better developed than verbal processing. Use of encoding strategies t is better developed d than auditory vocal processing. Short term auditory memory is better developed than long term verbal bl memory. Retrieval of information from short term memory is better developed than retrieval of verbal information from long term memory. Short term auditory memory is better developed than crystallized knowledge. 18

19 Verbal comprehension is better developed than processing speed. Verbal processing is better developed than speed of mental operation. Auditory vocal processing is better developed than visualmotor coordination. Processing of verbal stimuli is better developed than processing of nonverbal stimuli. Long term verbal memory is better developed than short term visual memory. Crystallized knowledge is better developed than processing speed. 19

20 Processing speed is better developed than verbal comprehension. Speed of mental operation is better developed than verbal processing. Visual motor coordination is better developed than auditory vocal processing. Processing of nonverbal stimuli is better developed than processing of verbal stimuli. Short term visual memory is better developed than longbl memory. term verbal Processing speed is better developed than crystallized knowledge. 20

21 Perceptual reasoning is better developed than working memory. Visual spatial processing is better developed than short term auditory memory. Immediate problem solving ability is better developed than use of encoding strategies. Interpretation or organization of visually perceived material is better developed than short term auditory memory. 21

22 Digit Span vs. Letter Number Sequencing Coding vs. Symbol Search Similarities vs. Picture Concepts 22

23 DS > LN This pattern may suggest that short term auditory memory for tasks that require rote memorization with minimal information processing is better developed than short term auditory memory for tasks that require rote memorization and information processing. LN > DS This pattern may suggest that short term auditory memory for tasks that require rote memorization and information processing is better developed than shortterm auditory memory for tasks that require rote memorization with minimal information processing. 23

24 CD > SS This pattern may suggest that visual perceptual symbolassociative skills are better developed than visual perceptual discrimination skills that do not involve association. SS > CD This pattern may suggest that visual perceptual discrimination skills that do not involve association are better developed than visual perceptual symbolassociative skills. 24

25 SI >PCn This pattern may suggest that abstract reasoning ability with verbal stimuli is better developed than abstract reasoning ability with visual stimuli involving familiar objects. PCn > SI This pattern may suggest that abstract reasoning ability with visual stimuli involving familiar objects is better developed than abstract reasoning ability with verbal stimuli. 25

26 When you begin comparing individual subtest scores to the mean of either all 10 subtest SSs or the mean of the VCI and PRI, you need to have a wide vocabulary at your disposal to describe the examinee s strength or weakness. You want to be able to put into layman s terms what cognitive domains, skills, and abilities each subtest taps into. Chapter 14 in the Flanagan and Harrison book have very good descriptions for all the Wechsler measures and to the extent the WAIS IV overlaps both the old WAIS III and the WISC IV, you need to draw upon their information. 26

27 To supplement the lack of an independent textbook for the WAIS IV, you are welcome to augment the missing data points in a variety of ways. The administration i ti manual is an excellent resource. I have posted links to some of Pearson s training materials on the Lectures page pg of our class website I have sumarized information from a variety of sources and relied heavily upon the material distributed by Pearson. 27

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29 Verbal concept formation and reasoning Also involves Crystallized intelligence Abstract reasoning Auditory comprehension Memory Associative i and categorical thinking Distinction between nonessential and essential features Verbal Degree of abstraction is an critical in score determinant 29

30 Word knowledge and verbal concept formation. It also measures an examinee s crystallized intelligence, fund of knowledge, Learning ability, long term memory, and the degree of language development. Other abilities that t may be used auditory comprehension and verbal expression 30

31 Measures ability to acquire, retain, and retrieve general factual knowledge. Also involves crystallized intelligence and long term memory. Other skills that may be used include verbal perception, verbal comprehension verbal expression 31

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33 Measures the ability to analyze and synthesize abstract visual stimuli. It also involves nonverbal concept formation and reasoning, broad visual intelligence, fluid intelligence, visual perception and organization, simultaneous processing, visual motor coordination, learning, and the ability to separate figure ground in visual stimuli 33

34 Involves fluid intelligence, broad visual intelligence, classification and spatial ability, knowledge of part whole relationships, simultaneous processing, and perceptual organization 34

35 Visual Puzzles examinee views a completed puzzle, and selects the 3 pieces from an array to make that puzzle Designed to measure nonverbal reasoning ability to analyze and synthesize abstract visual stimuli. Similar measures involve visual perception, broad visual intelligence, fluid intelligence, simultaneous processing, Spatial visualization and manipulation, and the ability to anticipate relationships among parts 35

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37 Key changes Added sequencing task Eliminated phonetically similar intra trial numbers All three tasks contribute tib t to Digit it Span subtest t score Because of the changes, the shift from one Digit Span task to another reflects cognitive flexibility and mental alertness. Copyright 2007 Pearson Education, inc. or its affiliates. All rights reserved. Why Add DS Sequencing? DS score criticized Forward doesn t really place much of a demand on WM until later trials h t h k t t i 37

38 Involves rote learning and memory, attention, encoding, and auditory processing. 38

39 Involves working memory, transformation of information, mental manipulation, and viso spatialimaging 39

40 Is similar to other tasks that are designed to measure working memory and mental manipulation 40

41 Measures mental manipulation concentration, attention, short and long term memory, numerical reasoning ability, and mental alertness May also involve sequential processing fluid, quantitative, and logical reasoning quantitative knowledge Omitted references to English measurement system and currency Decreased emphasis on mathematical skills to increase emphasis on working memory 41

42 PSI subtests measure the speed of mental and grapho motor processing 42

43 One of most important uses for this subtest is score comparison with Coding Allows pulling out fine motor (grapho motor) speed from mental processing speed. 43

44 Measure the speed of mental and grapho motor processing 44

45 The slides discussing and describing the WAIS IV subtests were developed by heavily drawing up a slide show published by Pearson Assessment. 45