title: Early interventions to prevent psychosis: systematic review and meta-analysis.
abstract: OBJECTIVE
  To determine whether any psychological, pharmacological, or nutritional interventions can prevent or delay transition to psychotic disorders for people at high risk.
  
  
  METHODS
  Systematic review and meta-analysis.
  
  
  METHODS
  Embase, Medline, PreMedline, PsycINFO, and CENTRAL were searched to November 2011 without restriction to publication status.
  
  
  METHODS
  Randomised trials comparing any psychological, pharmacological, nutritional, or combined intervention with usual services or another treatment. Studies of participants with a formal diagnosis of schizophrenia or bipolar disorder were excluded. Studies were assessed for bias, and relevant limitations were considered in summarising the results.
  
  
  RESULTS
  11 trials including 1246 participants and eight comparisons were included. Median sample size of included trials was 81 (range 51-288). Meta-analyses were performed for transition to psychosis, symptoms of psychosis, depression, and mania; quality of life; weight; and discontinuation of treatment. Evidence of moderate quality showed an effect for cognitive behavioural therapy on reducing transition to psychosis at 12 months (risk ratio 0.54 (95% confidence interval 0.34 to 0.86); risk difference -0.07 (-0.14 to -0.01). Very low quality evidence for omega-3 fatty acids and low to very low quality evidence for integrated psychotherapy also indicated that these interventions were associated with reductions in transition to psychosis at 12 months.
  
  
  CONCLUSIONS
  Although evidence of benefits for any specific intervention is not conclusive, these findings suggest that it might be possible to delay or prevent transition to psychosis. Further research should be undertaken to establish conclusively the potential for benefit of psychological interventions in the treatment of people at high risk of psychosis.
authors: National Collaborating Centre for Mental Health, Royal College of Psychiatrists, London, UK. tim.kendall@shsc.nhs.uk
authors: Megan R
authors: MR
authors: Stafford
authors: Hannah
authors: H
authors: Jackson
authors: Evan
authors: E
authors: Mayo-Wilson
authors: Anthony P
authors: AP
authors: Morrison
authors: Tim
authors: T
authors: Kendall
mesh_terms: D014150:Antipsychotic Agents / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D015928:Cognitive Behavioral Therapy; D003131:Combined Modality Therapy; D019587:Dietary Supplements; D042241:Early Diagnosis; D015525:Fatty Acids, Omega-3 / Q000627:therapeutic use; D006801:Humans; D011618:Psychotic Disorders / Q000175:diagnosis / Q000517:prevention & control* / Q000523:psychology / Q000628:therapy; D012307:Risk Factors
chemical_list: D014150:Antipsychotic Agents; D015525:Fatty Acids, Omega-3