Sex differences in auditory verbal hallucinations in early, middle and late adolescence: results from a survey of 17 451 Japanese students aged 12–18 years

OBJECTIVES: Women have higher rates of auditory verbal hallucinations (AVH) than men; however, less is known about sex differences in the prevalence of AVH in early, middle and late adolescence. We sought to elucidate the differences in the prevalence of AVH and to examine the degree to which these differences could be explained by differences in levels of depressive symptoms. DESIGN: We used a cross-sectional design and a self-reported questionnaire. SETTING: Participants were recruited from public junior and senior high schools in Tsu, Mie Prefecture and Kochi Prefecture, Japan. PARTICIPANTS: In total, 19 436 students were contacted and 18 250 participated. Responses from 17 451 students with no missing data were analysed (aged 12–18 years, M(age)=15.2 years (SD=1.7), 50.6% girls). MEASURES: AVH were assessed through one of four items adopted from the schizophrenia section of the Japanese version of the Diagnostic Interview Schedule for Children. Depressive symptoms were assessed using the 12-item General Health Questionnaire. RESULTS: The prevalence of AVH was 7.0% among early adolescents (aged 12–13 years), 6.2% among middle adolescents (aged 14–15 years) and 4.8% among late adolescents (aged 16–18 years). Being female was significantly associated with a higher prevalence of AVH through adolescence (OR=1.71, 95% CI 1.31 to 2.23 in early adolescence; OR=1.42, 95% CI 1.14 to 1.76 in middle adolescence; OR=1.52, 95% CI 1.23 to 1.87 in late adolescence); however, these differences became non-significant after adjusting for depressive symptoms (OR=1.21, 95% CI 0.92 to 1.60; OR=1.00, 95% CI 0.80 to 1.25; OR=1.16, 95% CI 0.93 to 1.44, respectively). CONCLUSIONS: Sex differences in auditory hallucinations are seen in both adult and youth populations. The higher rates of auditory verbal hallucinations seen in girls may be secondary to the differences in the rate of depressive symptoms.