I am confused about how to derive the FSIQ from the WISC IV. Is it simply adding the scaled scores of all 10 sub tests and that number is the FSIQ? In other words if the sum of scaled scores is 126, would that be the FSIQ? IF not, what would it be?

Adding the scaled scores is not how you get FSIQ. I believe you plug the sum of scaled scores into the WISC's proprietary scoring system to derive FSIQ. The scoring system is available only to testers. I do know that my DD's sum of scaled scores was a little over 10 points higher than her FSIQ if that's helpful.

Some posters on this board could tell you the FSIQ from the scaled scores. Maybe one of them will respond.

Thank you. I have found several sample tests that the sum of scaled scores equals the FSIQ. Hopefully someone will know exactly what the SSS of 126 converts to. Thanks again for your input.

You might consider moving this thread to testing and identification. People on that forum might have more info for you.

The max score is 160 and 19 (the max scaled score per sub test) is not a factor of 160. Therefore there has to be more to it than just summing the scaled sub test scores. I believe that the scored is derived by weighting the subtests by their perceived correlation with 'g' or general intelligence but I do not know the specifics.