Short-Term Improvement in Schizophrenia: The Contribution of Background Factors

Three categories of background factors were found to predict short-term improvement (symptom reduction) in schizophrenic patients receiving either placebo or one of three phenothiazines: general predictors, which applied equally to all treatments; predictors of outcome under placebo but not under drug treatment, or vice versa; and predictors of outcome under one phenothiazine but not another. Some variables found by other investigators to predict outcome were not found to be predictors in this study; it is suggested that these variables are not related to the specific outcome measure of symptom reduction.