The no control for medication is primarily based on the conclusions of Boutros 2008, a summary of spectral abnormality studies of schizophrenia. I reproduced a table from the paper in the appendix. What type of psych drugs were you working with?

As an aside drugs used to treat schizophrenia have especially nasty side-effects, such as weight-gain, reduction of white blood cells, and--ironically--some of the "negative" symptoms of schizophrenia when given to healthy people. In fact the Soviets used to use antipsychotics to torture political prisoners.

I concur that active EEG could lead to a much more accurate diagnosis, however we had access to quite a bit more resting data, and it does make the math easier (stationarity for one). Standardization of other factors would also probably increase accuracy, but once again, I was limited by my data. Since I'm no longer in academia, I won't be continuing the research, but hopefully further studies address these questions in more detail.