The 4-week and 26-week groups were formed on the basis of the guidelines for the optimal length of original therapeutic doses in the stabilization phase for schizophrenia (5, 7). The use of a no-dose-reduction group followed the updated treatment recommendation of the Schizophrenia Patient Outcomes Research Team (PORT) (4). The therapeutic dose was reduced to half in the first two groups because it proved to be relatively safe in preventing relapse and reducing side effects compared to the more radical reductions tested in earlier studies, i.e., to 25%, 20%, and 10% of the therapeutic doses effective in the acute phase of the illness (23, 31, 37–39).