Confusion over WISC-IV scores
By Inderbir Kaur Sandhu, Ph.D
Q: My son who turned 7 (5 days before he took the WISC-IV test) had the below results come back. Our district and the state of Ohio say that a score of 127 and above is considered gifted determined that he isn't gifted. His score was a 126. Because of this I have requested the overview and this is what he received.
Block Design raw score - 39 scaled score - 16 Similarities raw score - 10 scaled score - 10 Digit Span raw score -18 scaled score - 16 Picture Concepts raw score - 17 scaled score - 14 Coding raw score - 65 scaled score - 19 Vocab raw score 20 - scaled score - 10 Letter-Num Seq raw score 15 - scaled score 13 Matrix reasoning raw score 17 - scaled score 13 Comprehension raw score - 15 -scaled score 11 Symbol search raw score 29 - scaled score 13
Sum of Scaled scores:
Verbal Comprehension sum of scaled = 31 VCI 100 percentile rank of 50
Perceptual reasoning sum of scaled = 43 PRI 127 and percentile 96
Working Memory sum of scaled = 29 WMI 126 and percentile 96
Possessing Speed sum of scaled = 32 PSI - 133 and percentile 99
Full scale sum of scaled = 135 FSIQ = 126
I have several questions:
1) Can the FSIQ be used as a good indicator even though the Verbal is 26 pts - 33 pts lower then the other three (Perceptual, Working Memory, and Processing speed) It seems like this may be saying something. Is it saying he doesn't do well at verbal versus visual? Should the test be looked at differently because of this?
2) I have read that some people believe the cut off should be reduced to 120 vs 130 that some use because this test results on research show gifted kids scoring lower on this then the old version and the Stanford-Binet Intelligence Scale.
3) I guess I am wondering if I should have him retested because of this large variance?
4) He turned 7 5 days prior to the test being given. How would the test score results would have been if he had been 6 or taken the test 5 days earlier?
5) Did he reach the ceiling on any of the categories based on these scores?
Thanks for your help. Just frustrated because we feel he is bored but results didn't quite show he should be in the "gifted" category.
A: It appears that some WISC subtests are good measures of general intelligence; others are poor measures of general intelligence. WISC full scale IQ is not necessarily a more valid measure of intelligence, especially the kind of intelligence that is required to succeed in school. So at FSIQ 126, he should be in the above average category and I believe deserves differentiated curriculum. However, different schools have different policies with regards to this. The cut-off can be between 123-130; depends on the program and criteria used to select students by the respective organizations.
My concern is the VCI (read the technical terms in the WISC IV). Verbal Comprehension and Perceptual Reasoning tasks are heavily loaded on abstract reasoning ability and are better indicators of giftedness as compared to Working Memory and Processing Speed. In this case, there are extremes in both the scores, VCI being very low and PRI being very high. The subsets for VCI represent key clinical indicators of the cognitive strengths and weakness considered important to the assessment of learning disabilities, executive functions, attentional disorders, traumatic brain injuries, mental retardation, lead poisoning, giftedness, and various other medical and neurological concerns. On the other hand, the PRI emphasizes on fluid reasoning abilities as measured by the Matrix Reasoning subtest and Picture Concepts subtest – which your son scored highly.
The VCI describes verbal conceptualization, stored knowledge access and oral expression. The child is required to answer orally presented questions that assess common-sense reasoning, reasoning out or retrieving word associations and the ability to describe the nature or meaning of words. Verbal expression is required here. Low scores here may indicate a possible difficulty with language, weak fluid reasoning skills in verbal domain, or even possible hearing concerns.
The Verbal Comprehension and Perceptual Reasoning Composites are both very good indicators of giftedness; they assess verbal abstract reasoning and provide useful tests of visual reasoning with less timing emphasis. In your case, due to the significant difference between the VCI and PRI, the WISC-IV Full Scale IQ scores for the gifted may be difficult to interpret. In this case, you could consider the GAI (General Ability Index).
As a rule, the GAI would be considered in a number of clinical situations (though not limited to) as the following:
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a significant and unusual discrepancy exists between VCI and WMI,
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a significant and unusual discrepancy exists between PRI and PSI,
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a significant and unusual discrepancy exists between WMI and PSI, or
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a significant and unusual subtest discrepancy between subtests within WMI and/or PSI.
In your son’s case there is a significant and unusual discrepancy between VCI and WMI. This means, his GAI should be looked at. To retest using a standardized test, it may require a gap of 2 years. If you used the WISC-IV, perhaps you may want to try the SB-V. He reached the ceiling for the PS at the 99th percentile which indicates strong abilities to focus attention and quickly scan, discriminate between, and sequentially order visual information. It requires persistence and planning ability, but is sensitive to motivation, difficulty working under a time pressure, and motor coordination too.
It would be best for you to sought further help as a more detailed interpretation or other tests may be required to understand the difference in scores. It is possible that he has a language deficiency and perhaps you may want to consider a verbal test. A professional in this area may be best to seek help. Good luck!
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