Interpreting the WISC IV Score
By Inderbir Kaur Sandhu, Ph.D
Q: I would like some help interpreting my
son's WISC-IV scores, which I was told make him HG with some processing
issues, but no learning difficulty. He was 12 years and 11 months in
2012 when he took the test.
He has just started high school and is having problems with handwriting,
timed tests, accuracy and general organisation. He also has issues with
certain aspects of maths, especially those involving basic facts, space
and measurement. His fine motor skills are not very good but his
hand-eye coordination and gross motor skills are excellent. In many
circumstances he thinks and acts very quickly, but not all, because it
took him twice as long as it should have done to do some of the
cognitive test. He also complains of not having good short term memory
on occasion, yet most of the time his memory is impressive.
At primary school he gained very high marks in all subjects involving
multiple choice, written and oral language skills. But I am worried that
he will not be able to do so well under written exam conditions at high
school, unless he can use a computer or have extra time, which may not
be allowed because of his high achievement to date.
His scores are as follows:
I. VCI 153
II. PRI 117
Block Design 10
Picture Concepts 12
Matrix Reasoning 13
III. WMI 135
Digit Span 17
IV. PSI 109
Symbol Search 12
He hit ceilings on 13 out of 18 subtests, in WISC, WIAT and other areas,
some of which have not been given percentile scores.
So, I am confused about how these characteristics interrelate. I would
really appreciate more information about his processing issues and how
they can be addressed. With many thanks!
Based on the WISC IV composite score that you provided, your son has
scores in the superior range for VCI and WMI, superior for PRI and
average for PSI. His FSIQ is in the very superior range - based on what
you have given, it should be about 135, which qualifies him for
admission in most gifted programmes.
However, I do see your concern here. His processing speed is in the
average range in comparison to the other scores. It is not low but
compared to the other scores, it does appear to be a concern. His
ability in processing simple or routine visual material without making
errors is in the Average range when compared to his peers. It appears
that processing visual material quickly is an ability that he performs
less well than his verbal and nonverbal reasoning ability. Processing
speed is an indication of the rapidity with which he can mentally
process simple or routine information without making errors. Students
with superior reasoning ability often tend to perform less well,
although still adequately, on processing speed tasks.
In terms of intelligence, processing speed accounts for only 23% of the
variance in general intelligence. Is there any indication of ADHD - the
inattentive type? Apparently, lower processing speed scores could
indicate such concerns. There are children with ADHD who have IQ scores
in the gifted range, yet rather low processing speed. The WISC scores
alone are not able to make that diagnosis. However, this may not even be
the case for your son as you have not made a mention at all.
In some cases, the General Ability Index is used and the FSIQ gap is
really huge. However, in your son’s case, it would be a few points
higher (about 3 points). It does make more sense to identify gifted
children based on assessments emphasizing reasoning and providing them
with learning match. Most importantly, as in the case of your son, the
school should add accommodation based on his relative weaknesses to the
gifted accommodations. Therefore, an FSIQ score that “averages” overall
scores due to lower processing speed score in reality fails to identify
either the giftedness or the relative weaknesses.
It is has been noted time and again that gifted individuals may not be
fast processors. A good number may be very quick, others are reflective
(an incidence of being perfectionistic) and these traits indeed slow
down their speed. They also tend to show preference for any material
that is meaningful - this includes test material; hence all these
short-term memory test (such as coding) may not be seen as meaningful
and hard to interpret - this decreases their motivation.
There appears to be some kind of unevenness in development here, which
you must intervene real soon or it may possibly be a downhill journey.
For the issues he has in school, please speak to someone in authority in
school The fact that he scores very well on the WISC-IV indicates that
he is highly able and that with the right guide, he is an asset to all
around him. Further testing may be required - I am suspecting a learning
concern, which may need immediate attention. The school psychologist
would be the best person to refer or guide him for further
testing/counseling if the need be. If you are not satisfied with the
explanation, look for someone experienced in testing gifted children and
get the best possible recommendation in what can be done in your area.
Interesting read on processing speed: