A delusion is a firm and fixed belief based on inadequate grounds not amenable to rational argument or evidence to contrary, not in sync with regional, cultural and educational background.
I wonder if there is evidence that talking therapy can help with delusions (which people with schizophrenia often suffer from) - or not.
I assume that it depends on the form and severity of the delusion, and that there are mild forms which can be treated by talking therapy. Other forms may not be treatable by talking therapy.
If there are cases where talking therapy does help, is there evidence and are there (meta-)studies which techniques help best?
asking specific questions
telling specific things
contradicting or confirming the patient
trying to tangle the patient up in self-experienced contradictions