trying to decipher IQ percentile with the WISC IV

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So, I got the report in the mail today from the psychologist today and Im trying to understand the percentiles listed on her WISC IV results. I mean I know what a percentile *is* and what it means numerically, and the doctor listed what each range would mean in terms of what would be average, low average, borderline, low, etc. However, at the end she gave a percentile for "full scale IQ" instead of an IQ number, and cautioned that it appeared lower because my daughter's scores in certain types of learning were very low (like her verbal scores) and in other areas super high (like way high on perceptual reasoning skills)

Also the report said that this scatter of very high on perceptual reasoning & low score on verbal is very rare in the general population, like less than .3 percent.

o.O

Anyway, I tried to find something online which would give an IQ number to this full scale IQ percentile. Might be generational or something, but I can relate to the IQ numbers having taken those tests in the past, too.

Well, its much better to have a really high score somewhere than be average across the board

I did not receive any type of percentile on my son's WISC IV results, only a verbal, non-verbal and composite score. I am not sure about the percentile.

i have a book, "Special Educator's Complete Guide to 109 Diagnostic Tests", that has a section on the weschler tests, and gives some charts on how the results are interpreted in relation to score, iq range classification, and percentile. if you list what the percentile is that she received, and the exact wording to describe the percentile, i can try to look it up on the charts and see what it would correspond to. send me a private message if you'd rather not post it publicly.

btw, my son, too, had Verbal/Performance Scatter, and scored 21 pts higher on performance than verbal.

My son had high percentile scores on the first three parts of the WISC (which he has, at this point, taken about 4-5 times, as we've been constantly trying to understand his "differences"), and has consistently scored very low on the 4th part, which I believe is the PERCEPTUAL reasoning section.
That is why I am HERE! What does it all mean? And if these tests exist, and we can tease apart these areas of "intelligence", why can't this knowledge be translated into something concrete for educators to use to more effectively teach these students?

I could go on such a RANT! My son is 16, in 11th grade.....It's been a long, hard road. Wrong Planet is a good description of where we are living.

A separate IQ is calculated for each section and the full scale IQ is like the average IQ.

High and unusual scattering suggests learning disabilities, processing deficits, and can be indicative of certain types of brain damage in some situations.

Full scale IQ scores are often considered to be poor representations of the person's actual ability when high or unusual scattering is present.

Example: If in the math section, person A scores 89 on math facts (simple arithmetic), and 135 on calculations (advanced mathematics), their average IQ as pertains to math would be 112

If person B scores 89 on calculation and 135 on arithmetic, their average math score is also 112.

And if person C scores 111 on math facts and 113 on calculation, their average math score is also 112.

Even though they all have the same average math IQ, person A would be a good mathematician or physicist and a horrible accountant or cashier. Person B would be a good accountant or cashier but horrible mathematician or physicist.

Person C could be an accountant or cashier, maybe a high school math teacher.

You may also want to consider that IQ scores for spectrum children are completely useless and not representative of the measures they are trying to assess.

Full Scale IQ, as Chronos said, averages the verbal and performance sections on the WISC.

Often when there is a large discrepancy, they will not do a FSIQ but will give you something called a GAI. This is what they do when they figure the low score will lower the average so much as to give an inaccurate indicator of overall potential.

Both of my two who've been evaluated have very high verbal scores and very low performance scores. The GAI is close to the verbal score in both cases. An Average of the scores (FSIQ) would be very average really for both of them. It would vastly underestimate their potential.

Also, performance IQ is highly affected by processing speed. The verbal section is not timed.

Here are some approximate statistical equivalences:

2nd %ile - IQ 70
15th %ile - IQ 85
50th %ile - IQ 100
85th %ile - IQ 115
98th %ile - IQ 130

As Chronos said, the numbers are less meaningful if there is high or unusual scattering between the components.

Yes thank you for the hard numbers and scatter mention- this is the biggest part-- she scored unusually high one the perceptual reasoning skills, over 99 percentile on the visual reasoning. But when it came to her verbal scores, it was more like ten percentile (she's verbal herself, but grasps for vocabulary and asks people to repeat what they say a lot/repeats back what people tell her). The others were in lower average range, so it panned out to be a full spectrum IQ percentile Mega scatter as the psychologist said, and she mentioned something along the lines that this particular scatter is more with high functioning autistic folk, but the scatter tends to be reverse for Aspergers people, who have language down better.

In light of her results, I'm just trying to figure out how I, as a verbal/figurative person (INTP) can help out my uber concrete kid. Visual learning isn't my forte...