Gifted Issues Discussion homepage Forums Identification, Testing & Assessment Can WISC results be incorrect?

My 12yo has just taken a WISC test and I'm a bit perplexed by the results. We've always regarded her as gifted, but have never had the need to have her tested. We homeschool and so we've always been able to adjust the level of her work accordingly and have never felt that we needed to prove her intelligence to anyone. She has most of the "characteristics" that you read on gifted lists, including some of the quirks and sensitivities. She spontaneously started to read when she was 3 1/2, and we have always had people comment to us on how insightful and mature her thinking is.
So-when she needed a WISC score to help her gain entry into a program that she wants to do (only needing a moderately gifted score), we didn't have any concerns that it would be a problem. We did not need a full report, so we opted for the cheaper option (the only one we could afford), which was a "label" of each of the subtests (no numerical scores) and the Overall IQ. These were:

VCI - Superior Range
PRI - high Average
WMI - High Average
PSI - High Average
FSIQ - High Average

I am a school teacher, so I've seen the general range of abilities and she has never seemed in the average range (albeit high average) to me.I don't have any need for my child to be gifted, and I hope for my own sake that I'm not being biased, but I really doubt that she is high average. It just doesn't seem to me that a child of average intelligence would teach themselves to read at the age of 3 1/2, think at such an advanced level or have so many of the gifted characteristics if they weren't. She also solves logic/picture puzzles way faster than I do, and I was tested as "gifted' as a child.

So...my question is...can these these tests produce underestimated results? And if so, what is the purpose of them if they cannot be an accurate measure? Can giftedness be masked by a LD in the scores (not sure if she has one, just wondering)? Any other ideas for an unexpectedly low score? (she was not ill or tired and felt positive about the test - although she is a very reflective child and a perfectionist - so tends to take her time to make sure she is absolutely correct. maybe that could play a role?). Any ideas? I'm starting to worry myself that I have become one of those parents who completely overestimate their children's abilities - even though I'm often told I tend the other way! sigh!

blueskies - it can apparently be harder to score well as an older child. One of my children has been tested three times, another twice, we've used three different psychologists. The personality of the tester has had some impact, as have their health on the day and the particular test used. But for both children their VCI has not moved more than 3 points. Both girls have higher non verbal scores on the SB5, it seems to suit them better. My (more) 2e child has very variable WMI and PSI scores. Both children got their hightest scores with a gifted specialist that they both really clicked with... But fundamentally there is a certain level of consistency between tests and testers.

I've posted about this before so I won't go into too much detail, but my son bombed the WISC... his scores were awful (average to well below).

Our pediatrician warned against testing both kids because of behavioural issues (anxiety and attention). Turns out DS has ADHD and a language processing disorder which interfered with the results.

I'm HG, and both kids show all the signs (early milestones, behaviours, etc).

Our psychologist was perplexed at DS's results. "Take this with a grain of salt - it isn't right" and "medicate his ADHD and test him again in two years." She wrote right in the report that the scores were inaccurate: "due to his difficulties with language and sustained attention the results are not reflective of DS's true cognitive potential."

Anyway, test scores can definitely be wrong.

We were told when my son was tested that his scores were very likely an under-estimate of where he's really at. We are meant to go back and get him tested in a year or two to see where he's at.

For a child that has any learning disabilities or behavioral issues, or any signs of illness the day of the test, you can basically consider their test of be a 'basement' score... they are for sure at least at that level, possibly higher.

I haven't called to schedule DS to be retested this summer yet... I'll likely do it the summer after, as he's doing so well in his new school. The scores in and of themselves aren't particularly important for us.

This is where a conversation with the school psych and a full report can come in handy.

For each score, there is a range of statistical probabilities called the confidence interval. A 90% confidence interval means that if we were crazy enough to give this poor kid the same test on 10 different days, we would expect 9 of the scores to fall in this range. It is certainly possible that some of the scores have a confidence interval that pokes out into the superior range.

And yeah, a behavioral description can help you forecast how accurate those scores are. ADHD, anxiety (and ho boy! Autism!) can definitely affect scores. It is not uncommon for an assessor to write right into the report, "These scores should be interpreted with caution," if they think there really is some reason why the student's performance did not come anywhere near their potential.

Also, verbal ability is really privileged in school. It's not difficult to believe that a superior verbal ability gives off the impression of superior overall ability.

An underestimate for one child doesn't necessarily mean that they cannot be an accurate measure, just that the test didn't measure things well for that one child.

I'd expect reflectiveness and perfectionism to potentially impact the vocab portion of the VCI index if she just gave minimal answers and didn't expand and the PSI index b/c speed really helps there and slow reflection doesn't.

For comparison, how many 90th percentile type of kids do you know since that's about where Dottie puts the scores you have? Does she appear dramatically more able than these kids?

I, personally, don't give a lot of credence to personality measures of giftedness (i.e. exhibiting personality signs of giftedness) b/c I know a lot of kids who are sensitive, deep, etc. and who are not intellectually gifted. It's one of those, all squares are rectangles, but all rectangles are not squares things. OTOH, reading at 3.5 is something I'd put a lot of more weight on when assuming giftedness (again, depending on how you are defining reading). Most 3.5 y/os don't read at all, though.

The other thing to consider is what measures were used to identify you as gifted as a child. I, too, was labeled gifted as a child, but was never given an IQ test for that id. (I did take two IQ tests later, though, as a teen and adult.) I mention this to play devil's advocate b/c it is entirely possible for a child of a similar ability to your dd or even lower to be identified as gifted in a school system based on performance or the verbal ability alone or a number of other things.

Point being, your history (unless it includes very high IQ scores as part of that identification) and the personality characteristics don't necessarily mean that the # your dd got was off. The history of very early reading is of more significance for me.

All kinds of things can depress scores, many of which you mentioned: LDs, lack of cooperation, a tester who doesn't prod the child enough to tell more when more explicit answers would garner higher numbers, fatigue, hunger...

Cricket2 - both my husband and I were tested gifted. My husband is HG. I don't know what I am - I was only ever told that I had a high IQ. I do know that my brother, who was tested later than I was, is HG. We both scored in top 1% of our respective States in our final high school exams. We also have another child who is clearly HG, although we have never had him tested. He also read at 3 and was solving multiplication problems at 4. He is working 2-4 grade levels above his age in everything except handwriting (which is atrocious)and writing (which he hates doing). He is more obviously "gifted" than my 12yo, but we do not see an enormous difference. Our third child (6yo) has shown very little evidence of being gifted.

We suspect our 12yo may have some language-related issues as she does have trouble getting her thoughts out verbally. This is what really perplexed us about the results, which showed her as being strongest in verbal ability - we expected this index to bring her overall IQ down. Also, she doesn't go to school, so hasn't been labelled "gifted" by a school on the basis of her verbal ability alone. It was purely our observation based on her precocious milestones, her intense curiosity and attention span.

For example, she knew all her numbers and letters by 18 months, started reading whole words when she was 2-3 - and learnt to start decoding words phonetically when she was 3 1/2. By 4 1/2 she was reading short chapter books and has continued in this vein. Math is not her strong point, but she is well above average. I say this just to show that we had never really questioned her giftedness -surely this is not what you would expect from a child with "high average" intelligence . If she had been tested as a very young child, she would probably have scored in the gifted range. I've read in so many places that IQ is not meant to change, so this is why we can't understand what happened.

I'm regretting our decision to go with the cheap option of testing now. I probably should have sought out a psych with a speciality in gifted children who could give us a full report. However, like I said, we didn't expect it to be an issue, and just needed a "rubber stamp" to access a program. The frustrating thing is that if she had been at school, she could have used standardised State testing results for the application. She would have been fine with these, but as we home-school, she didn't have these results.

The more I've thought about this since I posted, the more I'm convinced there is something going on - whether it be the psych or some underlying LDs. I'm disappointed that such expensive testing has left us with more questions than answers!

Sorry if I was unclear. I did catch that she was homeschooled in your original post. I was more referring to the measures that were used to id you as gifted as a child and whether they may have been similar to the ones used when I was kid and what is used in my children's schools (which is not IQ and where high ability in one domain alone would be enough for such an id). My devil's advocate there was that, parental identification as gifted may or may not correlate with the child being gifted depending on what types of measures were used for said parental identification.

In any case, it sounds like your dd is more able than most of the high achiever but not quite gifted types I know. If you really feel that this program is something she'd enjoy and benefit from, is there any way for you to just give her a test similar to what the schools use yourself and use that for admission if they'd take something like, say, the ITBS? Many of those types of tests can be administered by parents even if you're not a psychologist.

I also do not put a ton of weight on the descriptions of early signs of giftedness - I have three levels of IQs among my kids (all have been tested, the older two tested more than once)... I feel confident that the testing results we have is relatively accurate and matches their intellectual abilities, but they were *all three* intensely curious and had many of the other characteristics that are often included in gifted characteristics lists. My latest reader was my EG ds.

I'm not saying that your dd isn't gifted; but if she is or isn't really isn't what the main issue is here - the issue (I think) is you want to qualify her for a program you think she would fit into easily and would enjoy. One way to get in was IQ testing; she didn't meet the bar to get in that way. You mentioned that if she was in school, she could get in via regular state testing (which, btw, is probably imo the *least* "gifted" type of test out there, unless it's truly ahead of grade level... but most state achievement testing only covers the state-mandated curriculum). Anyway, as a homeschool parent, you *should* be able to have your dd participate in state testing (at least you would be able to in my state). There also wouldn't be any cost associated with it here.

Another option that is most likely available is to request gifted testing through your school district (which here you can do, even if you are homeschooling). My only caveat on this is - she may test in the same range she tested in previously, and then that will be a part of her school district record.

Good luck - I hope you are able to get your dd enrolled in the program!

polarbear