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PSYCHOLOGICAL ASSESSMENT
Interpreting WAIS-III Scores

Here is a sample profile with examples of points you might consider (pass your mouse over each cell of the tables to see extra information pop up), followed by an example write-up from the information given. We interpret the test and communicate results backwards from the way scores are computed. That is, we interpret from most summarized to least summarized. First, we look at Global IQ and Index Scores. Next, we consider differences between these (I don't show that table here). Third, look at more narrowly defined strengths and weaknesses, as represented by significant subscale scores. Finally, examine performance on individual scales, and at times, the items within those scales. Consider all three sections discussed below. Following two of the tables are narratives that might derive from the tables. Usually any information derived from examining more specific items (i.e., at the subscale or item level) is used to temper statements made within the discussion of individual abilities. Combining the sample write-ups contained here could form the body of a short report.


GLOBAL IQ AND INDEX SCORES
(pass the mouse over table cells to highlight additional information)

IQ/INDEX SCORES VIQ PIQ FSIQ VCI POI WMI PSI
Sums of Scaled Scores 45 53 98 23 29 16 25
IQ/Index Scores 85 104 91 88 97 71 114
Percentiles 16 61 27 21 42 3 82
Confidence Intervals
       %
82-
95
97-
111
87-
95
83-
94
90-
104
66-
80
103-
121

Assuming a valid profile as above, I might conclude VIQ and PIQ are sufficiently unitary to be interpreted, but also that the Index Scores provide a good basis for describing abilities. I could begin my interpretation by saying something like the following:

Mr. Jones' overall performance on this measure suggests intellectual functioning in the Average to Below Average range. However, he clearly performs better on some intellectual tasks than others, suggesting that a global description of his intelligence may not be very informative. Specifically, Mr. Jones' verbal skills are a particular weakness area, with skills falling, on average, in the Below Average range. Overall, his verbal abilities lie around the 16th percentile Thus, he struggles with highly verbal tasks, including use of words, verbal reasoning, and sequential processing of information such as required by language. In contrast, spatial and perceptual skills are about average, with mean performance falling around the 61st percentile. This difference in abilities between verbal and perceptual-organizational abilities is perhaps an important one, although it should be recognized that differences of this magnitude are not uncommon, happening in about 9% of the population.


STRENGTHS AND WEAKNESSES WITHIN INDIVIDUAL SUBTESTS

SUBTESTS Scaled
Score
Mean
Score
Difference
from
Mean
Statistical
Significance
 .05  level
Strength
(+)
Weakness
(-)
Frequency of
Difference in
Standardiz.
Sample
Determining
Strengths &
Weaknesses
 Vocabulary 7 7.1 -.1 2.10   Check one:
 Similarities 10 7.1 2.9 2.77 S <10%
 Arithmetic 6 7.1 -1.1 2.63 Difference
 Digit Span 5 7.1 -2.1 2.42 from Overall
Mean
 Information 6 7.1 -1.1 2.34
 Comprehension 11 7.1 3.9 2.96 S <5% Difference
 Letter-Number Sequencing 5 7.1 -2.1 3.16 From Verbal
Mean and
 Picture Completion 9 10.9 -1.9 3.16 Performance
Mean
 Digig Symbol - Coding 12 10.9 1.1 3.04
 Block Design 10 10.9 -.9 2.94  Statistical
 significance &
 Matrix Reasoning 10 10.9 -.9 2.60  frequency of
 differences are
 Picture Arrangement 12 10.9 1.1 3.75  provided in
 Table B.3 of
 Symbol Search 13 10.9 2.1 3.54  Administration
 and Scoring
 Object Assembly 10 10.9 -.9 4.03  Manual

The table highlights two relative strengths. Note that he only performs about average on both, so it is important to communicate that they are relative strengths. Other scores approach but do not meet significance, so I treat them as relatively average. Even though my emphasis is on the strengths and weakness, because the average reader is often not well acquainted with the variety of intellectual functions assessed, I still spend some time making sure the non-highlighted attributes are given some attention (more in the previous section than here). Also note that I consistently try to place the abstract concepts of intelligence into practical, real-world implications. Given the strengths above I might conclude something like the following in my report:

In spite of overall verbal abilities mostly in the low average range, Mr. Jones does have some verbal skills that are relative strengths for him. Specifically, he has somewhat higher ability at using verbal skills and information to solve problems and perform verbal reasoning. For these abilities he performs at about the average range. He appears more adept, then, at using language to explain relationships, to form abstractions, and to solve practical problems. Thus, his ability to reason verbally might be relatively average, even though learned abilities like vocabulary and attentional skills may detract from his ability to use these reasoning skills effectively. This suggests he could readily take advantage of enrichment activities, giving him more information with which to use his fundamental reasoning abilities.


SCALING THE RAW SUBTEST SCORES

    Age-Adjusted Scaled Scores Reference
Group
SUBTESTS Raw
Score
Verbal Perf. VC PO WM PS Scaled
Scores
 Picture Completion 20   9   9     9
 Vocabulary 29 7   7       8
 Digit Symbol - Coding 83   12       12 11
 Similarities 23 10   10       10
 Block Design 41   10   10     10
 Arithmetic 9 6       6   7
 Matrix Reasoning 16   10   10     10
 Digit Span 10 5       5   5
 Information 9 6   6       7
 Picture Arrangement 18   12         12
 Comprehension 23 11           12
 Symbol Search 40   ( 13 )       13 12
 Letter-Number Sequencing 6 ( 5 )       5   5
 Object Assembly 34   ( 10 )         10
 Sums of Scaled Scores   45 53 23 29 16 25
    Verbal Perf. VC PO WM PS


updated August 1999