View Full Version : How Does ADHD Affect GAI Scores? (WAIS-IV)

03-08-17, 02:36 AM
I'm not entirely sure where this belongs, so I figured I'd start here, since I'm looking primarily for actual research data... (But let me know and I can move it elsewhere!)

I was wondering how ADHD might affect scores on the WAIS-IV (or the WISC for children)... (Part of my focus in grad school is twice exceptional (2e) students, or those with gifts/talents AND 1 or more disabilities.) When testing for gifted education, 2e students (of various disabilities, not just ADHD-*) are often missed because, among other things, their overall scores appear average or are deflated due to the disability.)

I can understand that (and some of the many ways of how) ADHD-* might affect the WM and PS indices...
E.g.: a) A timed test + spacey inattention = no bueno!
b) Those two indices (I think?) directly assess executive function (working memory / processing speed), which are all handled in the frontal lobe - the area that is typically seen as relatively weak in those with ADHD...

But what about the indices associated with the GAI? (the VCI and PRI)

I can see the information subtest being affected simply by not being as attuned to surroundings which are uninteresting, such as geography and so forth... As a result, the information simply isn't picked up and/or committed to memory.

Similarities might be deflated due to verbal / mental processing deficits (or at least from what I understand of my own experience with it). Basically, what the psychologist said, was that the idea is there, but due to deficits in mental categorization / organization and mental searching through that information, word-finding is problematic. I can definitely see how this could work against the person on this subtest as well.

But what about vocabulary, block design, visual puzzles, and matrix reasoning? Short of lacking in attention and perseverance on the test(s), are there other reasons that ADHD might affect these subtests? (And would medication (that works) have a positive effect on these subtests?)

Long story short, I'm having trouble finding studies which mention anything about the WAIS/WISC and whether ADHD affects the VCI/PRI scores, though many note effects on the WMI and PSI composite scores. (Though some score high on one or both due to novel circumstances, etc.) Is there any data out there on this?

(Side note: I'm not talking about using the WAIS (or any other single assessment aside from, perhaps, a rating scale such as the Brown ADD Scales) to *DIAGNOSE* ADHD, I'm speaking solely about the effects of ADHD on the WAIS-IV!)

Thank you in advance!

03-08-17, 05:20 AM
I dont know if I have the answer and I dont have any research to share but my son was diagnosed when he was 3.5. Once in school, he had many different tests while we were getting him set up with the IEP. Until 4th grade they were more age appropriate but in 4th grade if I remember he had the tests that you mentioned. Once thing that was interesting was the huge difference there was between his math type tests and verbal type tests. (I cant remember their specific names in the context you are asking). He had a ridiculously high verbal IQ and excelled in all the areas of language. In 6th grade he was reading, etc on a 12th grade level, yet his math skills were below average, yet if you verbally walked him through the math he did fine. One of his issues was dysgraphia which meant he was often messing up math due to his own handwriting. The same thing applied to anything he had to write out. He would have a scribe for standardized tests and that was when you could see an accurate measure of how he learned and what his skills were especially to his peers. Many times he would be reading his own tom clancy novel in 7th grade and if the teacher asked him a question about classwork he would be able to answer and go back to reading again. The testing was mostly difficult for him because the hyperactivity and straying off task made his results less valid in some cases, which is why the evaluators would note in their report how correct he often was, but how the results might not demonstrate that.

I dont know if thats what you were looking for or not. He is 21 now and doing amazing in college thanks to being able to use a laptop 90% of the time.

03-08-17, 10:34 AM
Thanks -- Math achievement was probably the WIAT, but if it was the WISC, Arithmetic and Digit Span are part of the Working Memory Index of the WISC/WAIS. (Coding and Symbol Search are in the Processing Speed Index.) I'm more talking about the Verbal Comprehension and Perceptual Reasoning scores, which you had said he really did well on.

Completely off-topic:
It's funny, I'm not "ridiculously high" in anything (110 VCI, 115 PRI, 95 WMI, and 102 PSI; for a FSIQ of 108), yet managed a 4.0 in my M.S.Ed (despite my BA and 10 years work experience being in an entirely different field), and am now in a doctoral program (where the average IQ is apparently 120 and up)... Even my GAI score (which takes out the WMI and PSI) is only 116, which at least puts 120 in the 95% confidence interval (barely), but definitely sticks me at the lower end of that average... Makes me wonder if I'm 'in over my head.'

I'd also never been diagnosed with anything, even though I had many of the same problems as your son. (Because this was the 80s, and because I technically never actually failed a subject, though a 119 on the Kaufman's Reading Achievement test (1 SD above) and an 87 on the Kaufman's Math Achievement test (close to 1 SD below average) should have told them something...)

At 36, they diagnosed ASD and ADHD-I via the assessment battery, along with slow processing speed for mental organization/searching of information (as mentioned in the OP) but isn't actually a diagnosis in itself. (And I apparently pinged the depression / anxiety scales of the PAI, which likely didn't help the WAIS scores, I suppose.)

Also, given the 1st percentile scores of the IVA-2 (how DO "normal" people actually DO that test?!?) a few weeks ago, it was clear attention is a problem and that my current meds clearly aren't doing jack, lol.

(Long story short, I went to the dr. to get meds to help with school a year ago. Given that I was always TOLD I had ADD, I assumed I had been diagnosed at a young age. Turns out, all my evals said I didn't actually qualify for anything... Guess I was too smart for my own good, even if I didn't qualify as gifted via IQ... But I'd be rich if I had a nickel for every time I heard "you're so smart, if you'd just [insert thing, e.g., use common sense!], you'd do so much better in school!!")

03-08-17, 11:16 AM
Think of the IQ tests as a floor, rather than as a ceiling.

While it does seem to be more common for ADHD to be associated with low performance and working memory scores, there's no single pattern that all people with ADHD have. There was a paper by Joel Nigg and colleagues (though I think the first author is someone else) published in the last 5 years or so that found that people with ADHD shared (a variety!) of test-score "profiles" with the general population, but simply had lower scores. I can try to dig it up if you want to read it.

If you were affected by distractibility or impulsive responding during the test, if you were anxious or depressed, if you were taking certain medications -- all of those could decrease your scores, even in the sections tapped by the GAI (which measure mostly verbal and visual skills).

Bottom line, though: They admitted you to the program --and on the basis of something other than IQ scores -- so they believe you're qualified. You should probably trust their judgment! (And if you do, at some point, feel like you're in over your head -- though don't go looking for trouble! -- look into accommodations, study groups, time management help, etc.)

Good luck in your program!

03-08-17, 06:56 PM
Thanks, Namazu - it's interesting to have been told to have ADHD since childhood by parents (even if everyone else said I was 'normal') and have self-diagnosed ASD since my late teens (I've always been really interested in psychology), but quite another to have someone actually confirm it...

I had found 1 study by Theiling and Petermann (2016), which basically said only WMI and PSI (and a marginal affect on PRI), but didn't really get into why. (Though I'm still parsing through the statistics pieces of it... Maths - of any kind - have never been my strong suit!)

With your suggestion, I found 2 articles which included Joel Nigg as author/co-author... (Searching (wais) AND (adhd) AND (nigg[au]))
"Executive functions and ADHD in adults: Evidence for selective effects on ADHD symptom domains" (2005) and "The role of inhibition in the production of disfluencies" (2010), though the latter did not use the WAIS, just a sentence-production task. But the former was almost 12 years ago, well outside the suggested 5-year mark, so I wasn't sure that was it either. If not, any further help with finding it would be appreciated!

While I hardly qualify as "gifted" based on MENSA-type classifications (though there are several other ways of defining the trait, such as the Renzulli 3-Ring Model), the 2e literature often talks about students "hitting a wall" at some point (anywhere from grade school to grad school), where they can no longer compensate for the disability... I guess I hit that wall, finally, in the doc program, so that's pretty much what I'm doing... baby-steps, I suppose...

Engelhardt, P. E., Corley, M., Nigg, J. T., & Ferreira, F. (2010). The role of inhibition in the production of disfluencies. Memory & Cognition, 38(5), 617-628. doi:10.3758/mc.38.5.617

Nigg, J. T., Stavro, G., Ettenhofer, M., Hambrick, D. Z., Miller, T., & Henderson, J. M. (2005). Executive functions and adhd in adults: Evidence for selective effects on ADHD symptom domains. Journal of Abnormal Psychology, 114(4), 706-717. doi:10.1037/0021-843x.114.3.706

Theiling, J., & Petermann, F. (2014). Neuropsychological profiles on the WAIS-IV of adults with ADHD. Journal of Attention Disorders, 20(11), 913-924. doi:10.1177/1087054713518241

03-09-17, 01:15 AM
I think the paper I was thinking of was this one:

Fair DA, D Bathula, MA Nikolas, JT Nigg. (2012) Distinct neuropsychological subgroups in typically developing youth inform heterogeneity in children with ADHD. ( Proc Natl Acad Sci U S A 109(17):6769-74. doi: 10.1073/pnas.1115365109.

The full text is online and free to read, but it's very technical. The gist seems to be that it's possible to group kids based on their testing profiles (not just "did well" or "did poorly", but specific patterns of how kids score in different areas).

Kids with ADHD don't form a unique group based on their testing profiles. They basically fit into the same groups as other kids, and tend to score a little lower than kids without ADHD.

I don't know if anyone's tried to replicate this yet (either in kids or in adults). I'm also not sure it is easily applicable to any one person's situation -- it doesn't provide a model for interpreting scores or anything -- but just makes the point that kids with ADHD, like kids without ADHD, also have other strengths and weaknesses.

03-09-17, 03:58 AM
Thank you for digging it up; I'll have to read that tomorrow, heading to bed in a moment... but random other q before I forget --
Being in the special education program, not an actual clinical psychologist, I don't generally get to see or really even talk about "normal" test results...

When you say "have other strengths and weaknesses," do typically developing kids usually show a subtest spread completely within the average range? Like, all scores within 1 SD above/below the mean (85-115 SS or 7-13 subtest scores)?

(It doesn't help that I also can't find the table which shows significance between scores (in Appendix B (Table B.1+) of the administration & scoring guide) online, even though I can find almost everything else...)

I know the sub-tests themselves are normed, but I'm not sure if they're normed independent of one another, or the entire test is normed together... or if that even matters (IE: the "average test-taker" typically scores "all in the average range" anyway)...