Are all psychological treatments for psychosis equal? The need for CBT in the treatment of psychosis and not for psychodynamic psychotherapy

Paley and Shapiro conclude in their review (Paley & Shapiro, 2002) that there is clear evidence that cognitive-behaviour therapy (CBT) results in clear clinical benefits for people with schizophrenia. They argue that this research could be informed by the wider psychotherapy literature, specifically the 'equivalence paradox' and 'investigator allegiance', and that psychodynamic treatments for schizophrenia should be investigated and evaluated. We argue that their review of the literature is incomplete. We conclude that there is little evidence to support the 'equivalence paradox' generally, and where it is suggested, as in depression, this is most likely an artefact. In schizophrenia, there is consistent evidence that supportive psychotherapy performs poorly in treating hallucinations. We argue for improved methodology in carrying out randomized controlled trials, which would minimize bias, such as from 'investigator allegiance'. We consider evaluation of psychodynamic psychotherapy to demonstrate equivalence to CBT as a low priority and unlikely ever to be attempted. We consider the research and clinical priorities to be the further developments of CBT and family intervention methods, which could have significant benefits for sufferers of schizophrenia and their carers.