If you'd rather have data than anecdote, http://www.marshall.edu/etd/masters/york-jennifer-2006-ma.pdf Note that the sample size of 33 doesn't necessarily qualify this as data, though. wink

"Although the screening instrument, the K-BIT IQ composite and the comprehensive instrument, the WISC-IV FSIQ were highly correlated, these two tests did not yield similar scores when administered to the same student. The K-BIT provided a significantly higher score (9 points) than the WISC-IV FSIQ."

I can't tell sample size here: http://preview.tinyurl.com/7waldz3 (This is a Google Books version of "Essentials of assessment with brief intelligence tests;" the table is on page 24.)