Background: It is increasingly understood that voice-hearing is neither a rare phenomenon experienced only by 'psychiatric patients' nor a meaningless symptom of a 'mental illness'.
Aims: To estimate the prevalence of voice-hearing in the adult general population.
Methods: PsycINFO and relevant literature reviews were searched for studies of the prevalence of verbal auditory hallucinations among adults.
Results: Seventeen surveys, from nine countries, were identified. Comparisons across studies were problematic due to differences in definitions, methodologies, and cultural factors. Prevalence ranged from 0.6% to 84%, with an interquartile range (excluding the highest and lowest quartiles) of 3.1%-19.5%, and a median of 13.2%.
Conclusions: Differences in prevalence can be attributed in part to differences in definitions and methodologies, but also to true variations based on gender, ethnicity and environmental context. The findings support the current movement away from pathological models of unusual experiences and towards understanding voice-hearing as occurring on a continuum in the general population, and having meaning in relation to the voice-hearer's life experiences.