In my kids, IQ and grade level equivalents have no relationship, while the scaled scores of index scores correlate with one another, at least within a standard deviation or so. Grade level equivalents appear to be produced by a random number generator.
Attempting to make correlations with grade level equivalents in our case are a fruitless endeavor.
Not a random number generator. Regression & curve smoothing. But still with little relationship to real-world instructional levels. Which is why the APA and NASP specifically dis-recommend the use of grade equivalents in assessment reporting and interpretation.
I know this. I should have maybe worded it "as if generated..." The GE does not correlate well across subtests, nor does the same scaled score equate the same number of grades ahead for a given subtests across the years (so a 130 in kindergarten is very different than in 4th). DS has identical scaled scores on different subtests, yet the GE is wildly different. Looking at his GE's on the latest round of WJ (which, granted, will qualify him for special ed), range from -2 to +14 of his current grade level, which the SS's range from low end of average to +78 points above the lowest score.
