Twelve-month prevalence and correlates of criminal offending in a nationally representative sample of people with psychotic disorders.

Objectives: We used a large, representative sample of adults with psychotic disorders (N = 1825) from the 2010 Australian national survey of psychotic disorders (Survey of High Impact Psychosis - SHIP) to report on 12-month prevalence of both any and violent criminal offending among people with psychotic disorders, and examine correlates of criminal offending, modelling the impact of clinical factors over known sociodemographic and behavioural risk factors.

Methods: Any past year criminal offending was the main outcome variable, based on self-reported criminal offending, charge and/or arrest. We assessed the additional impact of clinical variables over other risk factors associated with criminal offending. Odds ratio and 95% confidence intervals determined from logistic regression summarised the association of risk factors with offending outcomes.

Results: Of 1784 participants with valid responses, 305 (220 men, 85 women) reported criminal offending; 38 men and 6 women reporting some violent offending. Compared with non-offenders, younger age, male sex, homelessness, cannabis and other drug use, and past year delusions and mania were associated with offending in logistic regression models.

Conclusion: We found that known sociodemographic risk factors such as sex and homelessness were predictive of both any offending and violent offending. Other significant correlates of any offending behaviour were cannabis use, other illicit substance use and violent victimisation. Clinical factors including past year delusions, mania and deliberate self-harm, and premorbid personality disorder were associated with any offending but not with violent offending. Our study challenges the importance given to many clinical factors, especially in regard to risk of violent offending.