Score Discrepancy on the WISC-IV
By Inderbir Kaur Sandhu, Ph.D
Q: I have a seven year old boy who recently
had taken the WISC-IV. His scores came back a bit confusing. He is in
Verbal Comprehension 128-Superior
Perceptual Reasoning 106-Average
Working Memory 99-Average
Processing speed 73-BORDERLINE
Any info on the 30 point spread between scores is appreciated. It
appears he is gifted with a LD but what exactly is his LD how can we
help? He is having behaviour issues at school.
There appears to be a really large gap between the verbal comprehension
index compared to the rest of the index. The VCI is in the superior
range and the PSI is borderline which shows that the Full Scale IQ
should not be used.
You are right on track to be suspicious about the huge gap between the
scores and yes, there has to be a learning problem with such scores.
This is why the GAI (General Ability Index) should be used in this case
instead of the Full Scale IQ (FSIQ) - which is, if the composite scores
vary by 23 or more points - which is the case here.
In general the VCI is considered one of best predictors of overall
intelligence. Sometimes a low score occurs because the child has
acquired the information but does not have the expressive language to
demonstrate it. This is not the case here. The PSI which is the ability
to quickly and correctly scan, sequence, or discriminate simple visual
information, short-term visual memory; attention and visual-motor
coordination - appears to be very low which indicates a learning
I am not in a position to make a diagnosis here but it is clear that
there is an issue that needs intervention. And especially since your son
has just started formal schooling, the earlier the intervention, the
better the chances to cope with the concerns. I would strongly suggest
that you see a psychologist who may be able to suggest some further
tests that would confirm or rule out some concerns and intervene as soon
as possible. Best of luck!