The RIAS is intended to be a screener, and results should be interpreted that way. It's also advertised for reevaluations, when a comprehensive assessment has already been done, and an evaluator just wants to check that no drastic changes have occurred (like head trauma or the like). Please do not leap to any conclusions about emotional disturbance based on it.
If you want to retest, you may do so any time you think your child is ready for it, as there are no reported test-retest validity problems with the RIAS and other tests, like the WISC.
My personal experience with tracking the history of my students and how their RIAS scores have compared to other tests is that it has a more marked regression to the mean than other tests.
