I am not a testing expert... but fwiw I took a quick look at the link to see what the data was you were looking at... and I'm guessing that you're looking at the first table and comparing apples to oranges (WISC-IV with extended norms column) to the SB-5 column (?). If that's the comparison.. they are two different tests, it's not a comparison of WISC with and without extended norms.
BUT... then I became very curious about something - I thought that the way the "HG vs EG vs PG" would have been grouped would have been by percentile rank (since actual IQ scores are not exactly equivalent across tests)... but if you look at 99.9th percentile as listed on the DYS qualifications, 99.9 for WISC-IV is 145, and 99.9 for SB-V... but in the Hoagies table, 145 on the WISC is labeled the low end of HG, and 145 on the SB-V is the cut-off at the high end of HG, one point below EG.
JMO, but I've never put much thought or meaning into what a poster or anyone labels as HG/EG/etc. I'm more of a numbers person
polarbear
