Could someone please explain to me extended norms and how to calculate them. I've read a few things that if there are two sub categories (i.e. on the wisc iv)at 18 or 19 then you can use extended norms. My son had an 18 on block design and matrix reasoning. If so, can you tell me how to calculate it? I'm just interested why this would be something to be done. Thank you.
You need the raw scores to be able to calculate them, and as far as I know they only apply to WISC-IV. There is a techical report that you can find online.
http://www.pearsonassessments.com/N...C-8E4A114F7E1F/0/WISCIV_TechReport_7.pdf The test doesn't do a good job at discerning the highest levels, and this is an attempt to counter that. I think the extended norms give extra information; but that they have to be taken with a grain or two of salt.
You may also want to search for threads on extended norms, there have been a lot in the past. Extended norms are done on the SB-V too. As to your question of why you would need that information? I am not sure. I suppose it can tell you that they are even higher in an area, but when the area is already at 18/19 that is somewhat assumed...isn't it? those are just my thoughts, not official by any means. I am sure there are some other benefits. I guess for us it was useful to let schools know just how far above the norm he was. More useful for the schools probably than for us. We had already figured that. But I am sure some schools wouldn't even look at/accept/understand extended norms.
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