IQ "short" tests vs. Long tests?

[LynnS6]

Ds is participating in a research study (he's part of the 'control' group) and they administered a short for of the WISC to him. Is there any data on what the accuracy of this score is vs. the full test?

[ollyoxenfree]

Do you know how they shortened it? 

Did they eliminate some of the testing tasks?Or did they go through everything or most things but not test until they hit ceilings (for research purposes, maybe they just needed to know if the control group has a certain IQ range, but don't care about exactly how high)? 

I just googled "short form WISC" and came up with this paper. Perhaps they used the Dumont Willis Index-1 (DW-1). Without knowing how the researches shortened it, though, it's hard to analyze the results. I'd ask for some more specifics. Are they going to share the results or give you a report? 

[LynnS6]

I don't know how they shortened it. I think they did 1-2 verbal tests and 1-2 visual-spatial tests. They shared the overall score with me, which doesn't match other data I've got about ds.

I'm beginning to strongly suspect that ds is 2E and that he has some sort of delay in visual-spatial processing, so I'm wondering if that brought his overall score down.

I don't know if it's worth my asking them for the breakdown if they didn't do the whole thing.