Psychological Medicine

Original Articles

Prevalence of psychotic symptoms in childhood and adolescence: a systematic review and meta-analysis of population-based studies

I. Kellehera1 c1, D. Connora1, M. C. Clarkea1, N. Devlina1a2, M. Harleya1a2 and M. Cannona1a3 c1

a1 Department of Psychiatry, Royal College of Surgeons in Ireland, Dublin, Ireland

a2 St Joseph's Adolescent Unit, St Vincent's Hospital Fairview, Dublin, Ireland

a3 Department of Psychiatry, Beaumont Hospital, Dublin, Ireland


Background Psychotic symptoms occur more frequently in the general population than psychotic disorder and index risk for psychopathology. Multiple studies have reported on the prevalence of these symptoms using self-report questionnaires or clinical interviews but there is a lack of consensus about the prevalence of psychotic symptoms among children and adolescents.

Method We conducted a systematic review of all published literature on psychotic symptom prevalence in two age groups, children aged 9–12 years and adolescents aged 13–18 years, searching through electronic databases PubMed, Ovid Medline, PsycINFO and EMBASE up to June 2011, and extracted prevalence rates.

Results We identified 19 population studies that reported on psychotic symptom prevalence among children and adolescents. The median prevalence of psychotic symptoms was 17% among children aged 9–12 years and 7.5% among adolescents aged 13–18 years.

Conclusions Psychotic symptoms are relatively common in young people, especially in childhood. Prevalence is higher in younger (9–12 years) compared to older (13–18 years) children.

(Received March 09 2011)

(Revised November 30 2011)

(Accepted December 05 2011)

(Online publication January 09 2012)


c1 Address for correspondence: Dr I. Kelleher or Professor M. Cannon, Department of Psychiatry, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin 9, Ireland. (Email: (Email:


† These authors contributed equally to this work.