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DD6 is having WISC this week and I want to make sure we get the most out of this. Please let me know if I am getting the following right.

1) GAI can be calculated independently of the actual scores. What I mean is, kids don't have to hit a minimum number in any of the subtests. The way I understand it is GAI combines the verbal and the performance; doesn't consider working memory or processing speed.

2) Extended scoring can be used only when a child gets a ceiling in at least one subtest (or was it 2?). So, if a child gets an 18 or 19, then extended scoring can be used.

3) Does the tester have to know before hand about extended scoring? That is, can the tester stop the test because a child did not get the termination criteria (whatever many wrong in a row or total..) and then be unable to use extended scores? I know some testers might not be familiar with extended scoring, and I just want to know whether those can be calculated a posteriori.

4)The regular test consists of 10 subtests and 5 optional subtests. What should I know about those optional tests? Should I ask the tester to use all? We are looking at testing to further understand our DD and her challenges/strengths.
For example, her lowest score when she took WPSI-III a couple of years ago was Information. Back then, her general knowledge was very scattered, she knew a lot about obscure things but much less of the basics. Now that she has been reading for much longer, I am curious to see if this area continues to be a low one for her. Will Arithmetic tell us something that we wouldn't find out through achievement (later this month she will do WJ-III)?


Thanks for the clarifications!

I can't answer all of your questions since I don't know the answers to all of them, but here's what I know:

1). Yes, GAI can be calculated in any circumstance. It doesn't matter whether the GAI subtests are high or low or whether there's a large discrepancy between GAI and full scale IQ. Yes, GAI combines VCI and PRI and leaves out working memory and processing speed. However, GAI would be substantially discrepant from full- scale IQ only if the GAI subtests are substantially higher (more likely) or substantially lower than working memory and processing speed.

2) I don't know much about extended scoring, sorry. But my guess would be, whenever a child attains either an 18 or a 19, whatever composite score (index score, GAI, full-scale IQ) that is dependent on that subtest(s) can be recalculated using extended scoring. I don't know, however, whether a particular school would take extended scoring seriously, though.

3) I guess it depends on the individual tester whether he would stop the subtest just because the child reached the ceiling subtest score although not all questions have been administered. I think, however, that most testers and definitely a good tester would only stop if the termination criteria were met or if all the subtest questions were administered and not stop just because the child already answered enough for a ceiling subtest score. Extended scores can be calculated only if you know the raw score for individual subtests. However, often, parents are not reported raw scores, only scaled subtest scores and composite scores.

4) I think here the answer is simple: the more information you get the better, so if there aren't money or time issues, it's good to ask the tester to administer all 15 subtests. WISC Arithmetic tests solving arithmetic word-problems and should be close to Numerical Reasoning (or whatever it's called, I am not very familiar with WJ-III). I think the two main differences between WISC Arithmetic and WJ Numerical Reasoning are that on WISC, you can't use paper and pencil and have to do all the calculations in your head. Also, WISC Arithmetic is timed, while Numerical Reasoning might be untimed (although I don't know for sure).

I think it depends on what the purpose of the GAI is. If it is for gifted identification, the VCI/PRI spread may not be that relevant (as long as both are above the mean). If the GAI is to be used to identify a learning disablity, the spread would more important.

I've read of some districts giving quickie IQ tests which consists solely of VCI and PRI subtests. I think you lose valuable information in not doing the WMI/PSI subtests but if the schools are willing to do that much, it's probably worth the risks.

Wow. I hadn't heard of getting a WISC done and not getting a FSIQ.

The results are mainly for us. She is already at a gifted school. We'd like to get a better idea of where she is at in general terms (HG? less? more?).

She will have all four parts done, and I guess I need to give the tester a call and request her to do the 15 subtests, or at least all the ones in the VCI and PRI. While her processing speed was signficantly lower than the rest of her scores (86th percentile; it was certainly not too low. I have no idea how much that has changed in her, and how much those measures vary from the preschooler version to WISC.

I don't think the tester would charge us more to do more subtests. We are paying a lump sum for both achievement and IQ tests.

Thanks for the comments. I am going to see what I can find on the extended scores.

Thanks!

I just wanted to comment that in my case, I did all of the research you have done and it turned out that our Psychologist refused to calculate extended scoring and did not give us an accurate GAI. I did mention to her, before the testing began, that I wanted her to continue to ask questions until the termination criteria was met. (I truly think she did as I asked.) But when I also mentioned the possibility of my son hitting a ceiling and referred to extended scoring, I think it put off the tester, as if I knew more than they did.

It turns out that ds FSIQ was high enough, so I didn't have to press for extended scoring. (instead, I asked Dottie to help me calculate it! Thank you, Dottie!!)

It was not my goal to squeeze the absolute highest quantity from testing. I feel like I know my child pretty well (we homeschool.) I just wanted the opportunity to apply for DYS.
HTH
-cc

Thanks! I certainly don't want to alienate the tester; so I have wondered how to approach this conversation. I left a message for her, and I guess I will simply ask her what subtests she was planning on using. Depending on her answer, I might simply state that we want a more complete picture.

I am pretty sure my DD's overall score will not be DYS high, but I think there is a possibility she could be in the verbal area. If she were in that rank, then it would be good to have the option to apply, hence the extended scores question.

In any case, one of the things I am most interested about is how asynchrony development is playing in some behavioral issues we are seeing at home. I think there is a signficant dissonance between where she is at in terms of reading/writing and math. I hope that achievement testing will help us understand that better.

I really appeciate your comments. I am glad in your case, DS scored high enough that the GAI and the extended norms did not matter.

I know the psychologist frequently tests kids for admissions to the gifted schools in our area. I know that the schools are not that interested in processing speed. So, for instance, all of the local testers are used to calculating WPPSI scores with and without coding. I am extrapolating from that, that it will be standard procedure to calculate GAI.