.....My mom seriously wants to know.
So what is DD's real IQ from the WISC DD took. The FSIQ that was brought down by low, though still high average, processing speed and working memory, or the GAI that was calculated to be 160....or when you add in extended scoring and the GAI shoots up to 180. I was trying to explain all this to my mom's. We were at her house when we got the results, and just wanted a simple number...but I wasn't sure what to say since her FSIQ was pulled down by WM and Processing that were both at 2 SDs below her other scores. So I say the GAI would be the most "accurate" or what to say so to speak, Your thoughts on how to explained things like this with so many numbers Help!

From what I understand, the FSIQ gives the best overall picture of what you're capable of, as working memory and processing speed directly affect how well you can learn.

The psychologist should write in the report which they consider to be most accurate for your child.

But WM and PS are there for a reason, they have an impact in life and I am inclined to think have a huge impact in early schooling - where advanced reasoning is virtually irrelevant to curriculum goals. So the FSIQ is probably most relevant to whole child functioning, but GAI and extended GAI a better measure of pure reasoning ability (readiness for thinking about advanced math v. being best in the class at learning times tables and writing them out at speed in weekly tests as a crude example)...

If extended scales are being used to calculate her general ability index it indicates that the standard scales are insufficiently low to calculate her true GAI. Therefore, when reporting her GAI you should always use the extended scales, as the standard ones are not reflective of your daughter's true abilities (and in all honesty they probably should not have been computed either, as they are spurious figures).

The way it was explained to me was GAI was a better picture of reasoning ability. And FSIQ showed information about output. Thus, a child (like mine) would be frustrated with the inability to write as well as they could verbally output information. I was also told a child should be challenged to their ability, then accommodated for their weaknesses.

I will admit this is not happening for ds.

I'll respectfully disagree with this as a parent of a child with a significantly lower processing speed than other areas, and a higher GAI than FSIQ. What that difference tells you isn't about the "ability to learn" it's about the "ability to output" (processing speed), which can be as insignificant as the ability to make marks quickly on paper. Working memory relates to the ability to juggle multiple things in your head at one time - having a lower WM isn't going to mean a person isn't less capable of learning than a person with a higher WM, it just means they might learn in a different manner.

I also, personally, feel that there are a lot of things that aren't measured on IQ tests that will go into determining what any one person is capable of in life - motivation, circumstances, passion, interests.

Re the WISC (and other ability tests), I think that there is no real answer to the question "which number is 'more accurate' "... I think that if you have test results that you feel were obtained when your child was attentive and not distracted or feeling ill or whatever (ie, test results you trust), what you have are a set of numbers that *all* accurately reflect different types of abilities.

polarbear

Talking with your child's test administrator is often a good way to gain more information regarding your child's test results and score interpretations.

To gain helpful background information for understanding what the test administrator may say and what the score report contains, interested parents may want to look at free information provided to the public online by the test company.

For example, Pearson has several publications online easily found through search engines, which discuss when to use the General Ability Index (GAI). The Full Scale IQ (FSIQ), Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Cognitive Proficiency Index (CPI), Working Memory (WMI), and Processing Speed (PSI) are discussed. Myths are listed and countered with facts.

Many parents may find the time invested in reading information from a test company to be worthwhile in providing insight as to when to use each type of score, and how together the scores may provide the most complete picture of an individual's intellectual profile.

The WISC-IV provides a full-scale IQ (a measure of global general intelligence), a general ability index (based on perceptual reasoning and verbal comprehension), and a cognitive proficiency index (based on processing speed and working memory).

When there is a large discrepancy between the GAI and CPI, the full-scale IQ is not reflective of the child's true abilities and should not be computed. However, a large discrepancy may be indicative of certain conditions such as ADD, ADHD, and so on and so forth.

A high cognitive proficiency index is pertinent to the child's academic achievement as it frees up the potential for higher problem-solving; a child with a high GAI may be proficient at understanding a problem and the means of solving it, but holding that information in his or her head and manipulating it to achieve a correct result is dependent on the magnitude of his or her CPI.

That being said, a common personality trait among gifted students is a need for precision and accuracy. As a result, they will develop slow, meticulous responses to any given mental task. This personality trait will have the tendency to decrease his or her processing speed, and a common profile among gifted people of all ages is high verbal comprehension, perceptual reasoning, and working memory indices, accompanied with a relatively low processing speed index. However, it should be noted that this personality trait also has the tendency to inflate the other three indices on the Wechsler Battery, and so the full-scale IQ is still reliably measured by the test.

interesting debate but my response (simplistic...) at those levels why does your mom think it matters? what difference does she believe it makes?

Can you explain to them that all three scores have advantages and disadvantages but all three together give a comprehensive picture?

I'm not sure what you mean by the personality traits inflating the other three indices and therefore the FSIQ is still reliably measured by the test.

The aforementioned personality trait will deflate the processing speed index but inflate the other three indices (because the person will be able to comprehend more in general due to the slowness of pace and develop better reasoning skills, which does not equate to an increase in pure g, which is what the IQ test attempts to estimate).

Hmmm. I've not heard this before. What led you to believe this? Particularly about WMI? My ds's WMI certainly wasn't inflated by his average PSI.

I say this because it is clear that certain personality traits are deleterious to certain mental abilities, processing speed being one, and advantageous to others, e.g., verbal comprehension (the person who reads slower and has a need for precision is almost certainly more likely to comprehend more than another person with a similar level of g but will usually have a lower processing speed).

A person's level of g does not vary simply because one develops personality traits that are conducive to high scores on a given index or indices, and if IQ tests could yield deceptive results simply because one student has a need for precision and accuracy and another person does not, they would not be a reliable measure of g by any means, and yet the full-scale IQ's of different IQ tests all have very high correlations (e.g., the correlation between the WAIS-IV and the SB-V is r = 0.89).

To state it simply, if a person develops certain behaviors and traits that have an adverse or propitious affect on certain mental abilities, it will show up on other indices of a good IQ test. For example, a person who reads very slowly and has an obsessive need to understand all of the subject matter under immediate discussion is likely to have a very high verbal comprehension index, but this will be negated by a much lower processing speed index. A person whose verbal comprehension index is high as a result of his or her level of g will not have such a mitigation in processing speed.

As far as working memory is concerned, it is probably the least affected by the aforementioned personality trait; verbal comprehension, followed by perceptual reasoning, are the most highly inflated, while working memory could be not affected at all (although the child may have a somewhat higher arithmetic score due to an abnormal facility with quantitative reasoning as a result of obsessive tendencies that result in an "over-learning" of mathematics).

Yes, but the VCI on the WISC is not in fact a reading comprehensive measure--at least not as I understand it.

I'm sorry, but I'm just not convinced.

I couldn't imagine how reading comprehension wouldn't have a high correlation with verbal comprehension; clearly, the greater one's reading comprehension the more likely he or she will preform better on vocabulary and information; after all, the more information one comprehends while reading, the more likely he or she will store that information in his or her long-term memory. Also, the greater one's reading comprehension the more terms he or she is likely to comprehend and thus the larger his or her vocabulary is likely to be. Not only that, but according to Dr. Arthur Jensen, for adults a measure of reading comprehension relative to the general population is essentially as accurate a measure of g as a certified IQ test. Clearly, there is a very strong correlation between verbal comprehension and reading comprehension.

As far as not being convinced is considered; I would also pose the contrary example: consider a person who reads extremely rapidly but as a result comprehends little of what he or she is reading. He or she may preform very highly on processing speed, but is likely to preform comparatively poorly on verbal comprehension in particular.

One is able to estimate the g-factor using a method developed by Spearman known as factor analysis; as a general rule, factor analysis shows that the more diverse and different tasks measuring mental abilities one administers, and the higher the g-loading on those tasks, the greater the accuracy to which one can be sure one is measuring g.

If you are unconvinced of what I'm saying, you would have to believe that certain personality traits can alter one's IQ significantly, in which case you would have to believe that IQ tests are not a reliable measure of g. I would argue quite vehemently that one would not score well on all or even a large number of the sub-tests on the Wechsler battery without having a very high level of g and a very high level of g only. What are the chances that one, by sheer serendipity, would have all of the personality traits that are conducive to proficiency at tasks measuring abilities as different as vocabulary, block design, digit span, coding, and the like? Not only are these tasks only positively correlated due to the g-factor, they tend to be negatively correlated when g is factored out (for example, verbal comprehension and processing speed have a negative correlation when g is negligible for the aforementioned reasons).

So did I misunderstand your original assertion that a person's personality trait of meticulousness lowers their PSI and inflates the other three indices?

Not true at all for PRI at least. The 'blocks section' of the WISC IV is timed and I could see (via double mirror) my DD basically playing and exploring the potential of the blocks as well as checking and rechecking (perfectionism). While she solved every block task, she took her own time about it so only got credit for what she did within the time which held her PRI down to 145.

Tendency wouldn't mean absolute causality. Not true in one anecdotal case is different than something being wrong. I think you can find most of Frank22's points fairly well layed out in the book: Essentials of WISC-IV Assessment.

per KADMom's question:
"So did I misunderstand your original assertion that a person's personality trait of meticulousness lowers their PSI and inflates the other three indices?"

I think that is the inverse of what he originally was saying, which was that if the other three indexes are high and PSI is low, FSIQ is still a reliable measure. I think the statistics say that, and the presented supporting theory behind the statistics is that perfectionism can yield that pattern. I think block design can be a bit of a wash because it is timed, but it also favors a more complex carefulness to prevent accidental mistakes.

Of course it has been over twenty years since I took psychological testing, test design, and various statistics classes; techniques and theories (and my memory) may have changed radically since then.

And above all, most of us here are here because our kids are the exceptions that statistics do not account for. 1 in 10,000 isn't even noise in most of these test norms.

Welcome to the boards, Frank22.

I've read in several places (not to spark any controversy) that Working Memory is probably the best indicator of academic success in elementary school. The particular study I'm thinking of measured working memory at the beginning of a child's schooling (around age five) and their subsequent academic progress at around age twelve.

I (think) the authors of the study were stating that working memory seemed to be the deciding factor independent of IQ score. (although working memory at least on the WISC is part of FSIQ- so a bit confused). Also, working memory was shown to be independent of parent's level of education or socio economic background.

I would be interested in seeing how working memory plays out as these children age through high school and college as academic subjects become more complex. I probably have a pretty excellent working memory (self-assessed) and was stymied by calculus and economics.

I'd read that, also. I wonder if working memory can improve with age.

Then I still don't understand why, for instance, my ds's tester considered the GAI to be the best measure in ds's report, when the tester also stated perfectionism most likely being behind the PSI score.

Admittedly, there is still much I don't understand about IQ measurements and the tests to obtain them.

Zen Scanner you missed my point entirely. My point is that the notion that gifted but slow processing subjects have inflated PRI scores because their very slowness gives them more time doesn't hold water. The block design section is timed so 'slowness' is penalized.

Frank22 welcome to the board, btw.

It's ultimately the discretion of the tester, but there are a number of guidelines between Pearson's http://pearsonassessmentsupport.com/support/index.php?View=download&EntryID=353 and this article+research from the Gifted Development Center http://www.gifteddevelopment.com/About_GDC/whoaregiftd.htm .

I did not. Perhaps you missed my second entry on the subject.
"Sherman, if you would... "

My kid is on the other end of the perfectionism continuum, and wrecklessness hits hard on visual transfer tasks. Glancing at a 3 by 3 grid meaning to check position 2,2 and instead looking at position 1,2 is a problem.

The best measure of scholastic achievement to my knowledge is g, and not working memory. Some scholars have argued that working memory and g are one and the same, but the methods used to support this hypothesis are shoddy. Moreover, digit span forward is a poor measure of g, and I believe it was Terman who seriously considered removing it from the Stanford-Binet (although it was ultimately retained because of the clinically rich data it provided on the subject).

Thank you Zen Scanner and Madeinuk for the salutations.


Working memory increases with age up to a certain point, after which it begins to decline. However, up-to-date IQ tests (such as the WAIS) are age-normed and take into account such decline. The average digit span for a twenty year old, for example, is 7 digits, while the average for a person in his or her sixties would be about 5.5.

Thanks for the information, and yes, welcome to the boards!

Frank22, which IQ test do you think is the most reliable for identifying giftedness in children and adults?

You're welcome, and thank you for the greetings.


All IQ tests that purport to provide a so-called "quotient IQ," derived by dividing one's "mental age" by his or her "chronological age" are defunct measures of intelligence. Extant IQ tests rely on deviation IQ, which is based on one's z score (the amount of deviation he or she has from the mean). The present day understanding of g is akin to the understanding of the gene between the time of Gregor Mendel and the discovery of the DNA double helix by Watson and Crick; we know that g exists empirically due to the correlation between any and all mental abilities, no matter how diverse. However, we do not know what it is that physiologically causes for g, although it must be a property or properties of the brain that are involved in all thoughts involving a conscious choice. According to Dr. Arthur Jensen, who passed away in late October of 2012, with a concerted effort from pyschometricians and stable funding, this problem may be solved in the next one or two decades.

That being said, such classifications as "gifted" and "superior" are not meant to pigeonhole the subject, but instead provide an argot that is accessible to both the clinician and layperson alike, and it is known that all IQ tests will measure the g-factor in addition to a sort of "fudge-factor" of non-g factors; the more tests one administers with higher g-loadings and ever more differing mental abilities, the more one minimizes this fudge-factor and measures g more accurately.

Although I am not familiar with the vast welter of IQ tests available, the Wechsler intelligence tests are the most widely used IQ tests at the moment. They are excellently normed, and in certain age groups measure full-scale IQ up to 210 for the WISC-IV. I would also prefer the WAIS-IV over the WAIS-III for other reasons; the addition of "digit span sequencing" has made the digit span task much more highly g-loaded (the g-loading of digit span on the WAIS-IV is 0.72, as compared to 0.59 for the WAIS-III). Arithmetic on the WAIS-IV has also been made to include simpler but longer calculations, therefore increasing its working memory demands and g-loading. Also, the WAIS-IV measures full-scale IQ up to 160, as compared to 155 for the WAIS-III.

In general however, many of the IQ tests in present use (such as the Stanford-Binet, Woodcock-Johnson, Differential Abilities Scale, Cognitive Abilities Test, Otis-Gamma Test, and so on and so forth) are easily capable of assessing IQ's several standard deviations from the mean, and a child who scored a full-scale IQ of 130 or more did not attain such a score through luck or "having a good day," etc.

Thanks, Frank22!