Is there evidence that cognitive behaviour therapy is an effective treatment for schizophrenia? A cautious or cautionary tale?

Schizophrenia is a severe and disabling disorder with considerable psychological, social and economic costs. Over the last 15 years there has been a significant development in the use of cognitive behaviour therapy for psychosis (CBTp) in the treatment of schizophrenia, with 20 randomised controlled trials having been published. The majority of this work has been with alleviating medication resistant symptoms in chronic patients, but preliminary work has also been carried out with speeding recovery in acute schizophrenia and in relapse prevention and early intervention. A review of these studies indicates modest effect sizes, with the strongest evidence available for chronic patients. There is evidence that the effect size of the trials is significantly and negatively correlated to their methodological quality. We conclude cautiously that overall there is good evidence for the efficacy and effectiveness of CBTp in the treatment of schizophrenia.