Gifted Issues Discussion homepage Forums Identification, Testing & Assessment WISC-IV scoring discrepancy

My ds (age 7 y 1 mo at time of testing) recently completed the WISC-IV to see if he qualifies for the gifted program in our school district. He does, but I am puzzled by the results below and wondering if something more might be gleaned from them:

VCI 132
PRI 141
GAI 144
WM 107
PSI 80

FSIQ 125

I have researched how the WISC-IV is constructed, what the various scores are thought to represent, etc., including reading everything on Pearson Assessment's website. However, I thought I would still ask for input here. In particular, can anyone provide insight into the potential significance of the huge difference between the PSI (and, to a lesser extent, the WM) and the other scores?

Thank you in advance!

My DS's scores were
VCI 114
PRI 141
WM 110
PS 109

GAI 133

Neuropsych said that the PRI of 141 is an underestimate because DS has terrible fine motor skills and the test involved block design. Plus extended norms probably should have been computed since he got 18 and 19 on the other two subtests. So DS's PR score is much higher than everything else. I was the most worried about the much lower verbal score, but strangely, the neuropsych seemed most worried about processing speed. He said that DS would be able to understand advanced material (like math) but since his processing speed is average for his age, he may not be able to do complex work quickly or accurately. There are some concerns about ADHD based on how we was acting during testing (and probably the low PSI score). I'm not sure what a low WM means, but I think that's also common in ADHD. What were the subtest scores for PSI? For instance if just one was terrible and the rest Ok, that may give you a better idea. A low coding score might be a problem with motor skills or visual perception, for example.

Thank you for the reply, blackcat! I don't have the subtest scores in front of me, but will share them when I can.

Here are the scaled subtest scores for my DS:

-------------------------------------
VCI

Similarities 18
Vocabulary 16
Comprehension 12

PRI

Block design 16
Picture concepts 18
Matrix reasoning 16

WMI

Digit span 11
Letter-number sequencing 12

PSI

Coding 5
Symbol search 8
-----------------------------------------

A neighbor (who happens to be a teacher) also suggested that his relatively low coding score could be due to a vision problem - any other thoughts and/or suggestions?

The low coding score might be due to vision issues - the coding subtest requires a child copy a series of directional marks (if I am remembering it correctly - and I might not be lol!), and it's timed. The symbol search test also relies on vision - it requires that the child pick out identical symbols from a crowded field of random pictures. With scores that low in both, I'd be suspicious of vision. Fine motor skills can impact both subtests also, but are less likely to impact symbol search than coding.

If it is a vision issue, it could be straight-out eyesight (needs glasses) or it could be a muscle tone issue, tracking/convergence issue, etc. My dd had 20/20 eyesight at 7 yet scored very very low on coding and symbol search on the WISC because she had undiagnosed double vision and convergence/tracking issues due to muscle weakness in her eyes. The vision issues were *not* caught by our regular eye dr, we found out about the possibility of a vision issue through neurospych testing and were then referred to a developmental optometrist for an eval.

Have you noticed any challenges with school, homework, anything? If there is a vision challenge you might see things like not being enthusiastic about reading, or a lot of crumbs at the dinner table, or bumping into things or not being the most coordinated kid. If there's a fine motor issue, you might see things like sloppy handwriting or a reluctance to do writing assignments, taking a long time to learn to tie shoes, slow at getting dressed (buttons, zippers, etc).

Since the testing you had was for gifted program admission, I am guessing you didn't have any further testing to tease out why the WM and PSI were lower than the VIQ/PRI. If you'd been through a neuropsych eval, there would be additional testing that would help determine if there were fine motor or vision issues. Some of that testing you can get through other avenues if you do have a concern - an OT can assess fine motor, and a Developmental Optometrist can assess visual.

Hope some of that helps,

polarbear

I'm not sure what symbol search even is (sorry). Has he had an eye exam? Maybe try a developmental optometrist. Does he have problems tracking when reading or lose his place? Also ask him if when he's reading, the print overlaps or looks double, or is moving around. You could try putting a colored overlay on top and see if that helps. DS's OT did a visual perception test, called the TVPS, you could ask about that. It has 6 or 8 subtests to identify specific visual problems.

DD9 had a PSI of 80 as well. We have found out just today that she has an anxiety disorder and she is in counseling and will start medication. She has severe test anxiety and that's why here PSI was so low. Her VCI was 138, PRI was 135, and WMI was 123. So I would say there is something going on that needs to be checked out.

I was speaking to a administrator at a gifted school recently and discussing my DS6s wisc profile in which there is also a big gap between PSI and other indexes. They remarked that most of their students have "average" PSI scores. That my DS with a PSI in the 90s was not going to be that different from many students. Still I would guess that most of their kids are "average" at 105 or 110 or something, not 80.

The symbol search subtest is reliant on scanning and quick response time. It is a timed test. There is not a big working memory component, no verbal influence. There is a hint of analysis in that you have to recognize and discriminate one symbol from another. There is minimal fine motor.

The coding on the other hand, while also timed, has a input from working memory. It is sort of like the symbol search plus remembering and juggling things in your mind. Also no real deep analysis or verbal thinking input. There is a larger fine motor component.

So it makes sense to me midwestmom that if your DS has sort of average fine motor skills, or average visual processing speed, or just average speed at copying type tasks (dictation of sentences for example) in general, that the symbol search subtest could be a 8. The 8 in itself is not terribly low.

Then if you add in the working memory being average he can't use that as a relative strength on the coding subtest. My DS had a 150 on working memory, and that was enough to push up his coding subtest to a 10 I think it was, can't recall exactly. (His symbol search was 8). What I'm saying is with the coding subtest there is no way for your particular DS to mentally compensate for the absolute fine motor/visual/etc.

Ideally the symbol search and coding really measure what they are intended to measure, how fast you can process and respond in a speed task. I'm assuming above that scores really reflect ability. But personality can influence it too, like with Cassmo451's DD. A child who stops to say anything at all to the tester during the 2 minutes can wreck their score. A child who says to themself that this isn't that fun, that it's boring compared to the fun quiz type questions will have a poor score. If you are a perfectionist and go slowly in order to make what you are copying look exactly like the key you will not do well. If you are anxious about whether or not you are remembering things properly in the coding, if you always keep checking back that will lower your score.

Both subtests I think probably favor "sloppy sprinters."

So that would be my first question, whether the scores really represent their processing speed. If they do well at things like quick spelling tests, mad math minute, video games with multiple buttons/keys to hit, etc then probably the scores are not a good estimate and instead reflect something else coming in.

Maybe there is a component of both things. Some test anxiety plus purely average fine motor type skills, for example. Testing with an OT might help tease out what component is fine motor. The OT we recently went to also looked at visual processing.

If the scores do truly show their ability in processing speed then like my DS there is probably a chronic feeling of frustration, a bottleneck getting their complex thoughts out, particularly on paper. A difficulty showing the full extent of how they think. At school with average working memory and low or low average processing speed they may not come across nearly as bright as they are internally.

With my DS6 who truly does have motor planning/fine motor issues, school tasks are a big issue. The other kids finish mostly faster and can get the rewards of that whether it's reading their own books they brought or some fun center activity. DS has to finish while watching other kids having fun. Homework takes him too long and we have had no choice but to accommodate for that, it's not fair to a 6 or 7 year old for them to spend their evening on homework. He's very much at risk of feeling like a failure in school and that's in a typical public school. In a gifted program I assume it would only be worse because they might assume a little greater ability to organize or work quickly.

Is symbol search kind of like those "Where's Waldo" books where they have to find something? If so, I could see that being highly dependent on tracking or visual perception.

My DD doesn't have any handwriting issues but she is extremely slow with written work, esp if it involves copying. Her cursive packet looks perfect but it takes her forever. I can see her bombing the coding section. We are going to have her tested. My DS scored a "10" and even though his handwriting and fine motor is terrible, he probably rushed through it and therefore was able to do ok (it was still his lowest score, though).

Here's the descriptions from wikipedia:

"Coding — children under 8 mark rows of shapes with different lines according to a code, children over 8 transcribe a digit-symbol code. The task is time-limited with bonuses for speed."

"Symbol Search — children are given rows of symbols and target symbols, and asked to mark whether or not the target symbols appear in each row."

I think symbol search is maybe more like a super long kindergarten level matching worksheet than like a where's waldo. I think no one finishes it, that way they spread apart the levels of speed.