Religious psychopathology: The prevalence of religious content of delusions and hallucinations in mental disorder

BACKGROUND: Religious themes are commonly encountered in delusions and hallucinations associated with major mental disorders, and the form and content of presentation are significant in relation to both diagnosis and management. AIMS: This study aimed to establish what is known about the frequency of occurrence of religious delusions (RD) and religious hallucinations (RH) and their inter-relationship. METHODS: A review was undertaken of the quantitative empirical English literature on RD and RH. RESULTS: A total of 55 relevant publications were identified. The lack of critical criteria for defining and classifying RD and RH makes comparisons between studies difficult, but prevalence clearly varies with time and place, and probably also according to personal religiosity. In particular, little is known about the content and frequency of RH and the relationship between RH and RD. CONCLUSION: Clearer research criteria are needed to facilitate future study of RD and RH, and more research is needed on the relationship between RD and RH.