Psychotic-like experiences in non-clinical subgroups with and without specific beliefs

BACKGROUND: Assuming a transdiagnostic and extended psychosis phenotype, psychotic-like experiences (PLEs) and psychotic symptoms are on a phenomenological and temporal continuum between clinical and non-clinical populations. Recent research points towards differences in PLE proneness in different subgroups and clinical impact of different PLE subtypes. This study examines the prevalence of PLEs in three groups of individuals with and without specific sets of beliefs aiming to elucidate the question whether proneness to PLEs varies according to traditional versus less traditional supernatural beliefs. METHODS: The anonymized 16-item version of the Prodromal Questionnaire (PQ-16) was used to assess PLEs in three groups including individuals with religious beliefs (RB), belief in esoterism and paranormal phenomena (EB), and those embedded in scientific evidence approach and scepticism towards para-scientific theories (non-believers, NB). Male and female participants between 18 and 90 years were eligible for participation. RESULTS: The sample comprised 159 individuals including 41 RB individuals, 43 EB individuals, and 75 NB individuals. The mean PQ-16 score of the EB individuals (6.86 ± 4.13) was significantly higher compared to NB individuals (3.43 ± 2.99) and to RB individuals (3.38 ± 3.23) with almost twice the score (both p-values < 0.001). There was no significant difference between the PQ-16 scores of the NB group and the RB group (p = 0.935). No significant impact of age (p = 0.330) and gender (p = 0.061) was found on the PQ16-Score. Group affiliation to esoterism was associated with a higher PQ-16 score compared to group affiliation to religious beliefs (p < 0.001) and group affiliation to scepticism (p = 0.011), while the latter two did not differ significantly (p = 0.735). No significant difference was found between the three groups in the degree of distress related to the affirmatively answered PQ-16 items (p = 0.74). CONCLUSION: Under the assumption of a transdiagnostic psychosis phenotype, our findings provide more insight which subgroups within non-clinical samples have a higher likelihood of reporting PLEs.