A 2015 published study, "Hearing Voices in Different Cultures: A Social Kindling Hypothesis" compared the experiences of three groups of 20 participants who met the criteria for schizophrenia (n = 60) from three places, including San Mateo, California (USA), Accra, Ghana (Africa), and Chennai, India (South Asia). In this study, researchers found distinct differences among the participants experience with voices. In the San Mateo, CA sample all but three of the participants referred to their experience of hearing voices with "diagnostic labels, and even [used] diagnostic criteria readily", they also connected "hearing voices" with being "crazy". For the Accra, Ghana sample, almost no participants referenced a diagnosis and instead they spoke about voices as having "a spiritual meaning and as well as a psychiatric one". In the Chennai, India sample, similarly to the Ghana interviewees, most of the participants did not reference a diagnosis and for many of these participants, the voices they heard were of people they knew and people they were related to, "voices of kin". Another key finding that was identified in this research study is that "voice-hearing experience outside the West may be less harsh". Finally, researchers found that "different cultural expectations about the mind, or about the way people expect thoughts and feelings to be private or accessible to spirits or persons" could be attributed to the differences they found across the participants.
"An important finding highlighted in this study is that studies done by the World Health Organization (WHO) have found that "developing countries (non-Western) experience far higher rates of recovery from schizophrenia than Western countries". The researchers further articulate that these findings may be due to culturally specific meaning created about the experience of schizophrenia, psychosis, and hearing voices as well as "positive expectations around recovery". Research has found that auditory hallucinations and hallucinations more broadly are not necessarily a symptom of "severe mental health" and instead might be more commonplace than assumed and also experienced by people in the general population. According to a literature review, "The prevalence of voice-hearers in the general population: A literature review", which compared 17 studies on auditory hallucinations in participants from nine countries, found that "differences in the prevalence of [voice-hearing in the adult general population] can be attributed to true variations based on gender, ethnicity and environmental context". The studies took place from 1894 to 2007 and the nine countries in which the studies took place were the United Kingdom, Philippines, United States, Sweden, France, Germany, Italy, Netherlands, and New Zealand. The same literature review highlighted that "studies that [analyzed] their data by gender report[ed] a higher frequency of women reporting hallucinatory experiences of some kind". Although generally speaking hallucinations (including auditory) are strongly related to psychotic diagnoses and schizophrenia, the presence of hallucinations does not exclusively mean that someone has a psychotic or schizophrenic episode or diagnosis.