title: Violence in first-episode psychosis: a systematic review and meta-analysis.
abstract: BACKGROUND
  Violence towards others is a recognised complication of first-episode psychosis.
  
  
  OBJECTIVE
  To estimate the rate of violence and the associations with violence in first-episode psychosis.
  
  
  METHODS
  A systematic review and meta-analysis of 9 studies.
  
  
  RESULTS
  Pooled estimates of the proportion of patients with first-episode psychosis committing any violence, serious violence and severe violence were 34.5%, 16.6% and 0.6%, respectively. Violence of any severity was associated with involuntary treatment (OR=3.84), a forensic history (OR=3.28), hostile affect (OR=3.52), symptoms of mania (OR=2.86), illicit substance use (OR=2.33), lower levels of education (OR=1.99), younger age (OR=1.85), male sex (OR =1.61) and the duration of untreated psychosis (OR=1.56). Serious violence was associated with a forensic history (OR=4.42), the duration of untreated psychosis (OR=2.76) and total symptom scores (OR=2.05). Violence in the period after initiation of treatment for first-episode psychosis was associated with involuntary treatment (OR=5.71).
  
  
  CONCLUSIONS
  A substantial proportion of patients in first-episode psychosis commit an act of violence before presenting for treatment, including a number who commit an act of more serious violence causing injury to another person. However, severe violence resulting in serious or permanent injury to the victim is uncommon in this population.
authors.affiliation: The Prince of Wales Hospital, Randwick, School of Psychiatry, University of New South Wales, Sydney, Australia.
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Large
authors.forename: Olav
authors.initials: O
authors.lastname: Nielssen
mesh_terms: D015331:Cohort Studies; D003134:Commitment of Persons with Psychiatric Disorders / Q000331:legislation & jurisprudence; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006708:Homicide / Q000523:psychology / Q000706:statistics & numerical data; D006791:Hostility; D006801:Humans; D008297:Male; D012307:Risk Factors; D012559:Schizophrenia / Q000175:diagnosis / Q000453:epidemiology*; D012565:Schizophrenic Psychology; D014754:Violence / Q000523:psychology / Q000706:statistics & numerical data*