title: A comparison of statistical models in predicting violence in psychotic illness.
abstract: BACKGROUND
  The application of statistical modeling techniques, including classification and regression trees, in the prediction of violence has increasingly received attention.
  
  
  METHODS
  The predictive performance of logistic regression and classification tree methods in predicting violence was explored in a sample of patients with psychotic illness.
  
  
  RESULTS
  Of 2 logistic regression models, the forward stepwise method produced a simpler model than the full model, but the latter performed better. The performance of the classification tree appeared to be high before cross-validation, but reduced when cross-validated. The standard logistic model was the most robust model. A simplified tree with extra weight given to violent cases was a reasonable competitor and was simple to apply.
  
  
  CONCLUSIONS
  Although classification trees can be suitable for routine clinical practice, because of the simplicity of their decision-making processes, their robustness and therefore clinical utility was problematic in this sample. Further research is required to compare such models in large prospective epidemiologic studies of other psychiatric populations.
authors.affiliation: Health Services Research Department, Institute of Psychiatry, De Crespigny Park, London SE5 8AE UK.
authors.forename: Stuart
authors.initials: S
authors.lastname: Thomas
authors.forename: Morven
authors.initials: M
authors.lastname: Leese
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Walsh
authors.forename: Paul
authors.initials: P
authors.lastname: McCrone
authors.forename: Paul
authors.initials: P
authors.lastname: Moran
authors.forename: Tom
authors.initials: T
authors.lastname: Burns
authors.forename: Francis
authors.initials: F
authors.lastname: Creed
authors.forename: Peter
authors.initials: P
authors.lastname: Tyrer
authors.forename: Thomas
authors.initials: T
authors.lastname: Fahy
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015897:Comorbidity; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010554:Personality Disorders / Q000453:epidemiology; D011618:Psychotic Disorders / Q000453:epidemiology*; D012307:Risk Factors; D014754:Violence / Q000706:statistics & numerical data*