I don't know really anything about Keymath, but my daughter took that and then later was tested on WIAT-II so I have a score comparison if it's helpful.
Kymath-R (age 5y 10m)
Basic Concepts - 145 (>99)
Operations - 138 (99)
Applications - 138 (99)
Total Test - 145 (99)
WIAT-II (age 6y 6m)
Numerical Operations - 160 (>99.9)
Math Reasoning - 160 (>99.9)
Math Composite 160 (>99.9)
She did better on the WIAT-II and I don't know if its because she was older and better at testing, or if maybe there is a difference in how they compare scores; age vs. grade.
