Hi @BigScientist : Adding to @txnelson suggestion, be careful here. The two drugs are not independent (requirement for 1-way ANOVA). i.e., Patient 1 took both, patient 2 took both, and patient three took both. So, it is the within patient comparison that is appropriate here. This is a paired t-test. You can do this via Matched Pairs, or Fit Model. If your data is organized as above, the Fit Model with Result as "Y" and Patient and Drug as Model Effects will do the trick. And set Patient as Random (highlight Patient then click on Attribute and choose Random Effect).