WISC-IV Test Results Interpretation
By Inderbir Kaur Sandhu, Ph.D
Q: I recently had 7 years 6 months student
(boy) tested using WISC-IV. The
results were as follows:
VCI PRI WMI PSI
Similarities 4 Block Design 6 Digit Span 8
Vocabulary 4 Picture Concepts 2 Letter-Number
Sequencing 4 Symbol Search 6
Comprehension 3 Matrix Reasoning 6
How would you interpret these results? Should GAI be used in this case?
Also his VABS-II- Teacher Rating Form Adaptive Behaviour composite score
68 (C-67 ,DLK-70 and S - 76).
What does these results mean?
Based on the scores, the child performed in the Extremely Low range for
VCI and PRI, borderline for WMI and Low Average for PSI. The overall
score is in the Extremely Low range. This child would qualify for
special service in education.
The GAI can be considered if (however, not limited to, but includes the
a significant and unusual discrepancy exists between VCI and WMI;
a significant and unusual discrepancy exists between PRI and PSI;
a significant and unusual discrepancy exists between WMI and PSI; or
significant and unusual intersubtest scatter exists within WMI and/or PSI.
The index discrepancies can be reviewed by looking at the discrepancy
comparison critical value and base rate tables (in the manual). Based on
a quick view of the scores, the discrepancy between the said index (that
warrants for GAI) is not apparent. In fact, the GAI is sometimes used
alongside with the FSIQ to determine the impact of reducing the emphasis
on working memory and processing speed on the estimate of general
cognitive ability for children with certain difficulties. In this case,
the child's WMI and PSI appear to be the better range of scores.
The overall score indicates significant impairment of intellectual
functioning (usually IQ scores of below 70). This child would need
special provisions in education. Do see an expert to further evaluate
the specific intellectual functioning this child and get intervention
started as soon as possible. As he is young, early intervention would
prove to be extremely beneficial.
The Vineland Adaptive Behavior Rating Scales (VABS) is used primarily
with children and adolescents from birth to age 18 years, but may be
used adults suspected of having a mental handicap based on obtained IQ.
The scale measures adaptive behaviour in four major domains;
Communication, Daily Living Skills, Socialization, and Gross Motor
The VABS includes a number of items (critical behaviors) in each
Sub-domain, arranged by age at which the behaviours were present in the
original norm group. However, the scale is administered as a
semi-structured interview to an informant who knows the child well (there
are separate forms for parents and teachers). The interviewer asks
general questions pertaining to the child's functioning in each
sub-domain and uses the responses to rate the examinee on each critical
behavior item. Typical interviews require approximately one hour. Raw
scores are converted to IQ-type standard scores (mean: 100 sd: 15) for
each domain and for the composite adaptive behavior score. As for this
particular child, the composite score of 68 places him in the mildly
deficient adaptive functioning category. The Adaptive Behavior Composite
score is most useful in making decisions as to whether or not the
examinee's adaptive functioning is consistent with Full Scale IQ.
As suggested earlier, early intervention is very beneficial. Action
should be taken as soon as possible to get him the support and provision
he requires. All the best!